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    Impact of a tropical forest blowdown on aboveground carbon balance

    Study siteThis study was conducted at La Selva Biological Station, located in the lowland Atlantic forest of Costa Rica (10°26′ N, 83°59′ W). The mean annual temperature is 26 °C; mean annual precipitation is 4 m and all months have mean precipitation  > 100 mm39. La Selva has undulating topography, with elevation varying between 10 and 140 m above sea level. La Selva Biological Station includes multiple land uses; our analysis includes 103.5 hectares of forest, comprising 33.0 ha of old-growth forest and 70.5 ha of forests with past human disturbance (secondary forests, abandoned agroforestry, abandoned plantation, selectively-logged forests); here, we refer to all areas with past human disturbance as “secondary forests”. This study area does not include the full extent of old-growth or secondary forests at La Selva—we focused our drone data collection on this area because it contained the most severe apparent disturbance from the blowdown. Forests with past human disturbance have been naturally regenerating for a range of time (since 1955–1988); we excluded secondary forests with regeneration starting after 1988.Lidar dataWe use two airborne lidar datasets to quantify dynamics in canopy structure and ACD. Data were collected in 2009 and 2019 (Supplementary Table 2). Data from 2009 were collected by a fixed-wing aircraft over the entire reserve; data from 2019 were collected using the Brown Platform for Autonomous Remote Sensing40. We focused on an area 1.4 km2 in size that includes the region of most severe damage from the blowdown (Supplementary Fig. 1). Both lidar sensors were discrete-return systems. To minimize variation in lidar height estimates from variable laser beam divergence and detector characteristics, we only used data from first returns for all analyses. For the 2019 drone-based lidar with higher native point density and a wider scan angle range40, we limited our analysis to lidar returns with scan angle ± 15 degrees and randomly subsampled data to a homogenous resolution of 10 pts m−2. Previous research demonstrates that lidar data collected above densities of 1 pts m−2 have similar predictive power for determining many forest properties (including tree height, tree density, and basal area)41; both lidar datasets in this study are above this density threshold. All lidar data were projected using EPSG 32,616.For all lidar data, we calculated height above ground using a digital terrain model (DTM) created from lidar data collected in 2006 and validated using 4184 independent measurements within the old-growth forest (intercept =  − 0.406, slope = 0.999, r2 = 0.994, RMSE = 1.85 m; Supplementary Table 2)42. We verified that the horizontal geolocation accuracy with  More

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    1H NMR based metabolic profiling distinguishes the differential impact of capture techniques on wild bighorn sheep

    Examining the serum metabolome profiles of bighorn sheep captured by the three primary techniques used to capture wild ungulates revealed significant changes in polar metabolite levels between the different animal groups, and trends that persisted throughout the analyses when directly comparing, in a pairwise fashion, specific capture techniques. Results from PLS-DA modeling and analysis of the top 15 metabolites that contribute most (VIP  > 1.2) to the separation of the three capture groups revealed that amino acid levels of tryptophan, valine, isoleucine, phenylalanine, and proline were highest in animals captured by dart, with intermediate levels in animals capture using dropnets, and lowest in animals captured using the helicopter method (Fig. 3A). One-way ANOVA analyses identified additional amino acids that displayed similar decreasing level trends from dart to dropnet to helicopter capture (dart  > drop net  > helicopter) methods, and included arginine, asparagine, aspartate, cysteine, glutamate, and glutamine, glycine, histidine, leucine, lysine, serine, and tyrosine (Fig. 4). These metabolite level changes suggest a shift in amino acid metabolism, and a potentially higher catabolism of these compounds as a function of increasingly more energetically intense and possibly more stressful capture methods such as helicopter capture.Of these amino acids, aspartate, glycine, and glutamate function as precursors for neurotransmitter synthesis, and may therefore be valuable indicators of the capture techniques’ impacts on animal health and changes to their physiological state. Glutamate is a fundamental component of nitrogen excretion in the urea cycle, and its lower serum levels in animals captured by helicopter support the idea of altered metabolite flow through the urea cycle. In addition to these patterns, decreasing levels of aspartate were observed in samples of dropnet and helicopter captured animals compared to the levels found in the dart-captured animals. The change regarding urea cycle alterations also manifested itself in differential serum urea levels, with fold changes (FC) between the groups decreasing significantly with capture techniques, with a mean FC difference of 1.4 for the dart-captured group, 0.26 for the dropnet-captured group, and − 0.3 for the helicopter-captured animals (Supplementary Table S2). As urea recycling is a prominent feature of ruminant metabolism and urea flux can rapidly change, the urea concentration changes observed between the three capture techniques support an impact on urea cycle intermediates29. While the trend of an overall decrease in urea cycle intermediates parallels a similar trend in amino acid concentrations, the extent to which amino acid metabolism is linked to changes in urea cycle activity is difficult to evaluate due to the nature of nitrogen recycling in the rumen of these ruminants.Other metabolites found in significantly higher concentrations in the serum samples of dart-captured animals compared to the two other techniques included: formate, glucose, 3-hydroxybutyrate, dimethylamine, carnitine (Fig. 3A). Propionate, which was observed to be higher in the dart and dropnet captured animals than that of helicopter captured animals (Fig. 4) is of interest, as it is the main precursor for glucose synthesis in the liver of ruminants30, and potentially reflect a higher dependence of ruminants on gluconeogenesis due to the almost complete conversion of available dietary carbohydrates to volatile fatty acids in the rumen31. As animal capture via nets increases physical activity as the animals struggle to free themselves from entanglement, generally resulting in longer times animals are under physical restraint, as well as the increased physical exertion and stress as they attempt to flee the pursuing helicopter, the observed decrease in serum propionate levels may reflect increased needs to generate glucose de novo via gluconeogenesis.This interpretation of the metabolite data is reinforced by the observation of significantly elevated levels of O-acetylcarnitine in the drop net and helicopter net gun animal capture groups compared to the darted animals (Fig. 4). As an important element of the carnitine/acyl-carnitine shuttle and import of fatty acids into the mitochondria for β-oxidation, acyl-carnitine is a major contributor to the flow of acyl groups into the TCA cycle, and a robust indicator of cardiac output and, by extension, TCA cycle activity levels in mammals32. Additional metabolites that displayed distinctly increasing trends based on capture method (dart  More

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    Ixodiphagus hookeri wasps (Hymenoptera: Encyrtidae) in two sympatric tick species Ixodes ricinus and Haemaphysalis concinna (Ixodida: Ixodidae) in the Slovak Karst (Slovakia): ecological and biological considerations

    1.George, J. E., Pound, J. M. & Davey, R. B. Chemical control of ticks on cattle and the resistance of these parasites to acaricides. Parasitology 129(S1), 5353–5366 (2004).Article 
    CAS 

    Google Scholar 
    2.Abbas, R. Z. et al. Acaricide resistance in cattle ticks and approaches to its management: The state of play. Vet. Parasitol. 203, 6–20 (2014).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    3.Yessinou, R. E. et al. Resistance of tick Rhipicephalus microplus to acaricides and control strategies. J. Ent. Zool. Stud. 4, 408–414 (2016).
    Google Scholar 
    4.Bradberry, S. M. et al. Poisoning due to pyrethroids. Toxicol. Rev. 24, 93–106 (2005).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    5.Klainbart, S. et al. Tremor salivation syndrome in canine following pyrethroid/permethrin intoxication. Pharm. Anal. Acta 5, 320 (2014).
    Google Scholar 
    6.Antwi, F. B. & Reddy, G. V. P. Toxicological effects of pyrethroids on non-target aquatic insects. Environ. Toxicol. Pharmacol. 40, 915–923 (2015).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    7.Glorennec, P. et al. Determinants of children’s exposure to pyrethroid insecticides in western France. Environ. Int. 104, 76–82 (2017).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    8.Alfeev, N. I. The utilization of Hunterellus hookeri How. for the control of the ticks, Ixodes ricinus L. and Ixodes persulcatus P. Sch. with reference to peculiarities of their metamorphosis under conditions of the Province of Lenningrad. Rev. Appl. Ent. B. 34, 108–109 (1946).
    Google Scholar 
    9.Hu, R., Hyland, K. E. & Oliver, J. H. A review on the use of Ixodiphagus wasps (Hymenoptera: Encyrtidae) as natural enemies for the control of ticks (Acari: Ixodidae). Syst. Appl. Acarol. 3, 19–28 (1988).
    Google Scholar 
    10.Mwangi, E. N. et al. The impact of Ixodiphagus hookeri, a tick parasitoid, on Amblyomma variegatum (Acari: Ixodidae) in a field trial in Kenya. Exp. Appl. Acarol. 21, 117–126 (1997).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    11.Takasu, K. & Nakamura, S. Life history of the tick parasitoid Ixodiphagus hookeri (Hymenoptera: Encyrtidae) in Kenya. Biol. Control 46, 114–121 (2008).Article 

    Google Scholar 
    12.Rehacek, J. & Kocianova, E. Attempt to infect Hunterellus hookeri Howard (Hymenoptera, Encyrtidae), an endoparasite of ticks, with Coxiella burnetti. Acta Virol. 36, 492 (1992).CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    13.Plantard, O. et al. Detection of Wolbachia in the tick Ixodes ricinus is due to the presence of the hymenoptera endoparasitoid Ixodiphagus hookeri. PLoS ONE 7, e30692 (2012).ADS 
    CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    14.Bohacsova, M. et al. Arsenophonus nasoniae and Rickettsiae infection of Ixodes ricinus due to parasitic wasp Ixodiphagus hookeri. PLoS ONE 11, e0149950 (2016).PubMed 
    PubMed Central 
    Article 
    CAS 

    Google Scholar 
    15.Mather, T. N., Piesman, J. & Spielman, A. Absence of spirochete (Borrelia burgdorferi) and piroplasms (Babesia microti) in deer tick (Ixodes dammini) parasitized by Chalcid wasps (Hunterellus hookeri). Med. Vet. Entomol. 1, 3–8 (1987).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    16.Noda, H., Munderloh, U. & Kurtti, T. Endosymbionts of ticks relationship to Wolbachia spp. and tick-borne pathogens of humans and animals. Appl. Environ. Microbiol. 63, 3926–3932 (1997).CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    17.Ahantarig, A. et al. Hard ticks and their bacterial endosymbionts (or would be pathogens). Folia Microbiol. 58, 419–428 (2013).CAS 
    Article 

    Google Scholar 
    18.Duron, O. et al. Evolutionary changes in symbiont community structure in ticks. Mol. Ecol. 26, 2905–2921 (2017).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    19.Vila, A. et al. Endosymbionts carried by ticks feeding on dogs in Spain. Ticks Tick Borne Dis. 10, 848–852 (2019).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    20.Cooley, R. A. & Kohls, G. M. A summary of tick parasites. In Proceedings of the 5th Pacific Science Congress, Vol. 5, 3375–3381 (1934).21.Bowman, J. L., Logan, T. M. & Hair, J. A. Host suitability of Ixodiphagus texanus Howard on five species of hard ticks. J. Agric. Entomol. 3, 1–9 (1986).
    Google Scholar 
    22.Mather, T. N., Piesman, J. & Spielman, A. Absence of spirochete (Borrelia burgdorferi ) and piroplasms (Babesia microti) in deer tick (Ixodes dammini) parasitized by Chalcid wasps (Hunterellus hookeri). Med. Vet. Entomol. 1, 3–8 (1987).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    23.Hu, R., Hyland, K. E. & Mather, T. N. Occurrence and distribution in Rhode Island of Hunterellus hookeri (Hymenoptera: Encyrtidae), a wasp parasitoid of Ixodes dammini. J. Med. Entomol. 30, 277–280 (1993).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    24.Stafford, K. C. 3rd., Denicola, A. J. & Kilpatrick, H. J. Reduced abundance of Ixodes scapularis (Acari: Ixodidae) and the tick parasitoid Ixodiphagus hookeri (Hymenoptera: Encyrtidae) with reduction of white-tailed deer. J. Med. Entomol. 40, 642–652 (2003).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    25.Hu, R. & Hyland, K. E. Prevalence and seasonal activity of the wasp parasitoid, Ixodiphagus hookeri (Hymenoptera: Encyrtidae) in its tick host, Ixodes scapularis (Acari: Ixodidae). Syst. Appl. Acarol. 2, 95–100 (1997).
    Google Scholar 
    26.Lopes, A. J. O. et al. Parasitism by Ixodiphagus Wasps (Hymenoptera: Encyrtidae) in Rhipicephalus sanguineus and Amblyomma Ticks (Acari: Ixodidae) in Three Regions of Brazil. J. Econ. Entomol. 5, 1979–1981 (2012).Article 

    Google Scholar 
    27.Fiedler, O. G. H. A new African tick parasite, Hunterellus theilerae sp. n. Onderstepoort. J. Vet. Res. 26, 61–63 (1953).
    Google Scholar 
    28.Hoogstraal, H. & Kaiser, M. N. Records of Hunterellus theileri Fielder (Encyrtidae: Chalcidoidea) parasitizing Hyalomma ticks on birds migrating through Egypt. Ann. Ent. Soc. Am. 54, 616–617 (1961).Article 

    Google Scholar 
    29.Mwangi, E. N., Newson, R. M. & Kaaya, G. P. A hymenopteran parasitoid of the Bont tick Amblyomma variegatum Fabricius (Acarina: Ixodidae) in Kenya. Discov. Innov. 5, 331–335 (1993).
    Google Scholar 
    30.Shastri, U. V. Some observations on Hunterellus hookeri Howard, a parasitoid of Hyalomma-anatolicum anatolicum Koch, 1844 in Marathwada region Maharashtra State. Cheiron 13, 67–71 (1984).
    Google Scholar 
    31.Gaye, M. et al. Hymenopteran parasitoids of hard ticks in western Africa and the Russian Far East. Microorganisms 8, 1992 (2020).CAS 
    PubMed Central 
    Article 
    PubMed 

    Google Scholar 
    32.Oliver, J. H. A wasp parasite of the possum tick, Ixodes tasmani, Australia. Pan-Pac. Entomol. 40, 227–230 (1964).
    Google Scholar 
    33.Doube, B. M. & Heath, A. C. G. Observations on the biology and seasonal abundance of an encyrtid wasp, a parasite of ticks in Queensland. J. Med. Entomol. 12, 433–447 (1975).CAS 
    PubMed 

    Google Scholar 
    34.Heath, A. C. G. & Cane, R. P. A new species of Ixodiphagus (Hymenoptera: Chalcidoidea: Encyrtidae) parasitizing seabird ticks in New Zealand. N. Z. J. Zool. 37, 147–155 (2010).Article 

    Google Scholar 
    35.Costa Lima, A. The chalcid Hunterellus hookeri Howard, a parasite of the tick Rhipicephalus sanguineus Latreille, observed in Rio de Janeiro. Rev. Vet. Zoot. 5, 201–203 (1915).
    Google Scholar 
    36.Philip, C. B. Occurrence of a colony of the tick parasite Hunterellus hookeri Howard in West Africa. US Public Health Serv. Rpts. 46, 2168–2172 (1931).Article 

    Google Scholar 
    37.Bishopp, F. C. Record of hymenopterous parasites of ticks in the United States. Proc. Entomol. Soc. Wash. 36, 87–88 (1934).
    Google Scholar 
    38.Gahan, A. B. On the identities of chalcidoid tick parasites (Hymenoptera). Proc. Entomol. Soc. Wash. 36, 89–97 (1934).
    Google Scholar 
    39.Munaf, H. B. The first record of Hunterellus hookeri parasitizing Rhipicephalus sanguineus in Indonesia. South Asian J. Tropic. Med. Public Health 7, 492 (1976).CAS 

    Google Scholar 
    40.Cheong, W. H., Rajamanikam, C. & Mahadevan, S. A case of Hunterellus hookeri parasitization of ticks in Pentaling Jaya, Peninsula Malaysia. South Asian J. Tropic. Med. Publ. Health 9, 456–458 (1978).CAS 

    Google Scholar 
    41.Coronado, A. Ixodiphagus hookeri Howard, 1907 (Hymenoptera: Encyrtidae) in the brown dog tick Rhipicephalus sanguineus Latreille, 1806 (Acari: Ixodidae) in Venezuela. Entomotropica 21, 61–64 (2006).
    Google Scholar 
    42.Bezerra Santos, M. et al. Larvae of Ixodiphagus wasps (Hymenoptera: Encyrtidae) in Rhipicephalus sanguineus sensu lato ticks (Acari: Ixodidae) from Brazil. Ticks Tick Borne Dis. https://doi.org/10.1016/j.ttbdis.2017.03.004 (2017).Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    43.Řehaček, J. Uzitočný cudzopasnik. Enviromagazin 3, 19 (1998).
    Google Scholar 
    44.Collatz, J. et al. A hidden beneficial: Biology of the tick-wasp Ixodiphagus hookeri in Germany. J. Appl. Entomol. 135, 351–358 (2011).Article 

    Google Scholar 
    45.Tijsse-Klasen, E. et al. Parasites of vectors—Ixodiphagus hookeri and its Wolbachia symbionts in ticks in the Netherlands. Parasit. Vectors 4, 228 (2011).CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    46.Ramos, R. A. et al. Occurrence of Ixodiphagus hookeri (Hymenoptera: Encyrtidae) in Ixodes ricinus (Acari: Ixodidae) in southern Italy. Ticks Tick Borne Dis. 6, 234–236 (2015).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    47.Sormunen, J. J. et al. First evidence of Ixodiphagus hookeri (Hymenoptera: Encyrtidae) parasitization in Finnish castor bean ticks (Ixodes ricinus). Exp. Appl. Acarol. 79, 395–404 (2019).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    48.Krawczyk, A. I. et al. Tripartite interactions among Ixodiphagus hookeri, Ixodes ricinus and deer: Differential interference with transmission cycles of tick-borne pathogens. Pathogens 9, 339 (2020).PubMed Central 
    Article 

    Google Scholar 
    49.Pervomaisky, G. S. On the infestation of Ixodes persulcatus by Hunterellus hookeri How. (Hymenoptera). Zool. Zh. 22, 211–213 (1943).
    Google Scholar 
    50.Alfeev, N. I. & Klimas, Y. V. Experience in cultivating ichneumon flies, Hunterellus hookeri, obtained from United States, which destroy ixodid ticks of Soviet fauna. Priroda 2, 98–101 (1938).
    Google Scholar 
    51.Brumpt, E. Utilisation des insectes auxiliares entomophages dans la lutte contre les insectes pathogenes. Presse Med. Paris 36, 359–361 (1913).
    Google Scholar 
    52.Klyushkina, E. A. A parasite of the ixodid ticks, Hunterellus hookeri How. in the Crimea. Zool. Zh. 37, 1561–1563 (1958).
    Google Scholar 
    53.Slovak, M. Finding of the endoparasitoid Ixodiphagus hookeri (Hymenoptera, Encyrtidae) in Haemaphysalis concinna ticks in Slovakia. Biologia 58, 890 (2003).
    Google Scholar 
    54.Brumpt, E. Parasitisme latent de l’Ixodiphagus caucurtei chez les larves gorgées et les nymphes á jeun de divers ixodines (Ixodes ricinus et Rhipicephalus sanguineus). Comptes Rendus de l’Académie des Sciences de Paris 191, 1085–1087 (1930).
    Google Scholar 
    55.Boucek, Z. & Černy, V. A parasite of ticks, the chalcid Hunterellus hookeri in Czechoslovakia. Zool. Listy 3, 109–111 (1954).
    Google Scholar 
    56.Heglasová, I. et al. Ticks, fleas and rodent-hosts analyzed for the presence of Borrelia miyamotoi in Slovakia: The first record of Borrelia miyamotoi in a Haemaphysalis inermis tick. Ticks Tick Borne Dis. 11, 101456 (2020).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    57.Nosek, J. The ecology, bionomics and behavior of Haemaphysalis (Haemaphysalis) concinna tick. Z. Parasitenkd. 36, 233–241 (1971).CAS 
    PubMed 
    PubMed Central 

    Google Scholar 
    58.Nosek, J. The ecology and public health importance of Dermacentor marginatus and D. reticulatus ticks in central Europe. Folia Parasitol. 19, 93–102 (1972).CAS 

    Google Scholar 
    59.Széll, Z. et al. Temporal distribution of Ixodes ricinus, Dermacentor reticulatus and Haemaphysalis concinna in Hungary. Vet. Parasitol. 141, 377–379 (2006).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    60.Harnok, S. & Farkas, R. Influence of biotope on the distribution and peak activity of questing ixodid ticks in Hungary. Med. Vet. Entomol. 23, 41–46 (2009).Article 

    Google Scholar 
    61.Bartosik, K., Wiśniowski, L. & Buczek, A. Abundance and seasonal activity of adult Dermacentor reticulatus (Acari: Amblyommidae) in eastern Poland in relation to meteorological conditions and the photoperiod. Ann. Agric. Environ. Med. 18, 340–344 (2011).PubMed 
    PubMed Central 

    Google Scholar 
    62.Egyed, L. et al. Seasonal activity and tick-borne pathogen infection rates of Ixodes ricinus ticks in Hungary. Ticks Tick Borne Dis. 3, 90–94 (2012).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    63.Hornok, S. et al. Ixodid ticks on ruminants, with on-host initiated moulting (apolysis) of Ixodes, Haemaphysalis and Dermacentor larvae. Vet. Parasitol. 187, 350–353 (2012).CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    64.Buczek, A. et al. Threat of attacks of Ixodes ricinus ticks (Ixodida: Ixodidae) and Lyme borreliosis within urban heat islands in south-western Poland. Parasit. Vectors 7, 562 (2014).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    65.Chitimia-Dobler, L. Spatial distribution of Dermacentor reticulatus in Romania. Vet. Parasitol. 214, 219–223 (2015).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    66.Pfäffle, M., Littwin, N. & Petney, T. Host preferences of immature Dermacentor reticulatus (Acari: Ixodidae) in a forest habitat in Germany. Ticks Tick Borne Dis. 6, 508–515 (2015).PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    67.Collatz, J. et al. Being a parasitoid of parasites: Host finding in the tick wasp Ixodiphagus hookeri by odours from mammals. Ent. Exp. Appl. 134, 131–137 (2010).Article 

    Google Scholar 
    68.Takasu, K. et al. Host recognition by the tick parasitoid Ixodiphagus hookeri (Hymenoptera: Encyrtidae). Environ. Entomol. 32, 614–617 (2003).Article 

    Google Scholar 
    69.Demas, F. A. et al. Cattle and Amblyomma variegatum odors used in host habitat and host finding by the tick parasitoid, Ixodiphagus hookeri. J. Chem. Ecol. 26, 1079–1093 (2000).CAS 
    Article 

    Google Scholar 
    70.Alfeev, N. I. & Klimas, Y. V. On the possibility of developing ichneumon flies, Hunterellus hookeri in climatic conditions of the USSR. Sovet. Vet. 15, 55 (1938).
    Google Scholar 
    71.Logan, T. M., Bowman, J. L. & Hair, J. A. Parthenogenesis and overwintering behavior in Ixodiphagus texanus Howard. J. Agric. Entomol. 2, 272–276 (1985).
    Google Scholar 
    72.Wood, H. P. Notes on the life history of the tick parasite Hunterellus hookeri Howard. J. Econ. Entomol. 4, 425–431 (1911).Article 

    Google Scholar 
    73.Cooley, R. A. & Kohls, G. M. Egg laying of Ixodiphagus caucurtei du Buysson in larval ticks. Science 67, 656 (1928).ADS 
    CAS 
    PubMed 
    Article 

    Google Scholar 
    74.Hu, R. Identification of the wasp parasitoid of the deer tick, Ixodes dammini, in Rhode Island and its implication in the control of Lyme disease. M.S. thesis, University of Rhode Island, USA (1990).75.Mwangi, E. N. et al. Parasitism of Amblyomma variegatum by a hymenopteran parasitoid in the laboratory, and some aspects of its basic biology. Biol. Control 4, 101–104 (1994).Article 

    Google Scholar 
    76.Hu, R. & Hyland, K. E. Effects of the feeding proces of Ixodes scapularis (Acari: Ixodidae) on embryonic development of its parasitoid, Ixodiphagus hookeri (Hymenoptera: Encyrtidae). J. Med. Entomol. 35, 1050–1053 (1998).CAS 
    PubMed 
    Article 

    Google Scholar 
    77.Knipling, E. F. & Steelman, C. D. Feasibility of controlling Ixodes scapularis ticks (Acari: Ixodidae), the vector of Lyme disease, by parasitoid augmentation. J. Med. Entomol. 37, 647–652 (2000).Article 

    Google Scholar 
    78.Stafford, K. C. 3rd., Denicola, A. J. & Magnarelli, L. A. Presence of Ixodiphagus hookeri (Hymenoptera: Encyrtidae) in two Connecticut populations of Ixodes scapularis (Acari: Ixodidae). J. Med. Entomol. 33, 183–188 (1996).PubMed 
    Article 

    Google Scholar 
    79.Cole, M. M. Biological control of ticks by the use of hymenopterous insects. A review. World Health Organization (WHO/EBL/43.66) 43, 1–12 (1965).
    Google Scholar 
    80.Hoogstraal, H., Santana, F. J. & van Peenen, P. F. D. Ticks (Ixodoidea) of Mt. Sontra, Danang, Republic of Vietnam. Ann. Ent. Soc. Am. 61, 722–729 (1968).CAS 
    Article 

    Google Scholar 
    81.Zchori-Fein, E. et al. A newly discovered bacterium associated with parthenogenesis and a change in host selection behawior in parasitoid wasps. PNAS 98, 12555–12560 (2001).ADS 
    CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    82.Giorgini, M. et al. Rickettsia symbionts cause parthenogenic reproduction in the parasitoid wasp Pnigalio soemius (Hymenoptera: Eulophidae). Appl. Environ. 8, 2589–2599 (2010).Article 
    CAS 

    Google Scholar  More

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    Biobased and mechanically stiff lignosulfonate/cationic-polyelectrolyte/sugar complexes with coexisting ionic and covalent crosslinks

    1.Andrady AL. The plastic in microplastics: a review. Mar Pollut Bull. 2017;119:12–22.CAS 
    Article 

    Google Scholar 
    2.Akdogan Z, Guven B. Microplastics in the environment: a critical review of current understanding and identification of future research needs. Environ Pollut. 2019;254:113011.CAS 
    Article 

    Google Scholar 
    3.Dilkes-Hoffman LS, Pratt S, Lant PA, Laycock B. The role of biodegradable plastic in solving plastic solid waste accumulation. In: Al-Salem SM, editor. Plastics to energy. New York: William Andrew Publishing; 2019. p. 469–505.4.Reichert CL, Bugnicourt E, Coltelli MB, Cinelli P, Lazzeri A, Canesi I, et al. Bio-based packaging: materials, modifications, industrial applications and sustainability. Polymers. 2020;12:1558CAS 
    Article 

    Google Scholar 
    5.Reglero Ruiz JA, Trigo-López M, García FC, García JM. Functional aromatic polyamides. Polymers. 2017;9:414.Article 

    Google Scholar 
    6.Pilato L. Phenolic resins: a century of progress. New York: Springer; 2010.7.Ko HU, Zhai L, Park JH, Lee JY, Kim D, Kim J. Poly(vinyl alcohol)–lignin blended resin for cellulose-based composites. J Appl Polym Sci. 2018;135:46655.Article 

    Google Scholar 
    8.Shikinaka K, Nakamura M, Otsuka Y. Strong UV absorption by nanoparticulated lignin in polymer films with reinforcement of mechanical properties. Polymer. 2020;190:122254.CAS 
    Article 

    Google Scholar 
    9.Kargarzadeh H, Galeski A, Pawlak A. PBAT green composites: effects of kraft lignin particles on the morphological, thermal, crystalline, macro and micromechanical properties. Polymer. 2020;203:122748.CAS 
    Article 

    Google Scholar 
    10.Matsuoka T, Nonaka H. Wet extrusion of wood powder using a cellulose derivative. Jpn TAPPI J. 2020;74:516–24.Article 

    Google Scholar 
    11.Shen X, Berton P, Shamshina JL, Rogers RD. Preparation and comparison of bulk and membrane hydrogels based on Kraft-and ionic-liquid-isolated lignins. Green Chem. 2016;18:5607–20.CAS 
    Article 

    Google Scholar 
    12.Li H, Sun JT, Wang C, Liu S, Yuan D, Zhou X, et al. High modulus, strength, and toughness polyurethane elastomer based on unmodified lignin. ACS Sustain Chem Eng. 2017;5:7942–9.CAS 
    Article 

    Google Scholar 
    13.Dehne L, Vila C, Saake B, Schwarz KU. Esterification of Kraft lignin as a method to improve structural and mechanical properties of lignin-polyethylene blends. J Appl Polym Sci. 2017;134:44582.Article 

    Google Scholar 
    14.Dick TA, Couve J, Gimello O, Mas A, Robin JJ. Chemical modification and plasma-induced grafting of pyrolitic lignin. Evaluation of the reinforcing effect on lignin/poly (L-lactide) composites. Polymer. 2017;118:280–96.Article 

    Google Scholar 
    15.Ushimaru K, Morita T, Fukuoka T. Moldable and humidity-responsive self-healable complex from lignosulfonate and cationic polyelectrolyte. ACS Sustain Chem Eng. 2018;6:14831–7.CAS 
    Article 

    Google Scholar 
    16.Ushimaru K, Hamano Y, Morita T, Fukuoka T. Moldable material from ε-poly-l-lysine and lignosulfonate: mechanical and self-healing properties of a bio-based polyelectrolyte complex. ACS Omega. 2019;4:9756–62.CAS 
    Article 

    Google Scholar 
    17.Hellwig M, Henle T. Baking, ageing, diabetes: a short history of the Maillard reaction. Angew Chem Int Ed. 2014;53:10316–29.CAS 
    Article 

    Google Scholar 
    18.Henning C, Glomb MA. Pathways of the Maillard reaction under physiological conditions. Glycoconj J. 2016;33:499–512.CAS 
    Article 

    Google Scholar 
    19.Ushimaru K, Morita T, Fukuoka T. Bio-based, flexible, and tough material derived from ε-poly-l-lysine and fructose via the Maillard reaction. ACS Omega. 2020;5:22793–9.CAS 
    Article 

    Google Scholar 
    20.Ushimaru K, Morita T, Fukuoka T. A bio-based adhesive composed of polyelectrolyte complexes of lignosulfonate and cationic polyelectrolytes. J Wood Chem Technol. 2020;40:172–7.CAS 
    Article 

    Google Scholar 
    21.Zhang ZH, Zeng XA, Brennan CS, Ma H, Aadil RM. Preparation and characterisation of novelty food preservatives by Maillard reaction between ε-polylysine and reducing sugars. Int J Food Sci Technol. 2019;54:1824–35.CAS 
    Article 

    Google Scholar 
    22.Lay M, Thajudin NLN, Hamid ZAA, Rusli A, Abdullah MK, Shuib RK. Comparison of physical and mechanical properties of PLA, ABS and nylon 6 fabricated using fused deposition modeling and injection molding. Compos B Eng. 2019;176:107341.CAS 
    Article 

    Google Scholar 
    23.Bunn HF, Higgins PJ. Reaction of monosaccharides with proteins: possible evolutionary significance. Science. 1981;213:222–4.CAS 
    Article 

    Google Scholar 
    24.Suarez G, Rajaram RAMA, Oronsky AL, Gawinowicz MA. Nonenzymatic glycation of bovine serum albumin by fructose (fructation). Comparison with the Maillard reaction initiated by glucose. J Biol Chem. 1989;264:3674–9.CAS 
    Article 

    Google Scholar 
    25.Kim C, Yoshie N. Polymers healed autonomously and with the assistance of ubiquitous stimuli: how can we combine mechanical strength and a healing ability in polymers? Polym J. 2018;50:919–29.CAS 
    Article 

    Google Scholar 
    26.Gong JP, Katsuyama Y, Kurokawa T, Osada Y. Double-network hydrogels with extremely high mechanical strength. Adv Mater. 2003;15:1155–8.CAS 
    Article 

    Google Scholar 
    27.Gong JP. Why are double network hydrogels so tough? Soft Matter. 2010;6:2583–90.CAS 
    Article 

    Google Scholar 
    28.Ducrot E, Chen Y, Bulters M, Sijbesma RP, Creton C. Toughening elastomers with sacrificial bonds and watching them break. Science. 2014;344:186–9.CAS 
    Article 

    Google Scholar 
    29.Neal JA, Mozhdehi D, Guan Z. Enhancing mechanical performance of a covalent self-healing material by sacrificial noncovalent bonds. J Am Chem Soc. 2015;137:4846–50.CAS 
    Article 

    Google Scholar 
    30.Nakajima T. Generalization of the sacrificial bond principle for gel and elastomer toughening. Polym J. 2017;49:477–85.CAS 
    Article 

    Google Scholar 
    31.Yamini G, Shakeri A, Zohuriaan-Mehr MJ, Kabiri K. Cyclocarbonated lignosulfonate as a bio-resourced reactive reinforcing agent for epoxy biocomposite: from natural waste to value-added bio-additive. J CO2 Util. 2018;24:50–8.32.Szabó G, Romhányi V, Kun D, Renner K, Pukánszky B. Competitive interactions in aromatic polymer/lignosulfonate blends. ACS Sustain Chem Eng. 2017;5:410–9.Article 

    Google Scholar 
    33.Lee SI, Chun BC. Effect of EGMA content on the tensile and impact properties of poly (phenylene sulfide)/EGMA blends. Polymer. 1998;39:6441–7.CAS 
    Article 

    Google Scholar 
    34.Yang Y, Duan H, Zhang S, Niu P, Zhang G, Long S, et al. Morphology control of nanofillers in poly (phenylene sulfide): a novel method to realize the exfoliation of nanoclay by SiO2 via melt shear flow. Compos Sci Technol. 2013;75:28–34.CAS 
    Article 

    Google Scholar 
    35.Tao X, Nonaka H. Wet extrusion molding of wood powder with hydroxy-propylmethyl cellulose and with citric acid as a crosslinking agent. BioResources. 2021;16:2314–25.CAS 

    Google Scholar 
    36.Hasegawa D, Teramoto Y, Nishio Y. Molecular complex of lignosulfonic acid/poly (vinyl pyridine) via ionic interaction: characterization of chemical composition and application to material surface modifications. J Wood Sci. 2008;54:143–52.CAS 
    Article 

    Google Scholar 
    37.Wei C, Zhu X, Peng H, Chen J, Zhang F, Zhao Q. Facile preparation of lignin-based underwater adhesives with improved performances. ACS Sustain Chem Eng. 2019;7:4508–14.CAS 
    Article 

    Google Scholar  More

  • in

    Accurate detection and quantification of seasonal abundance of American bullfrog (Lithobates catesbeianus) using ddPCR eDNA assays

    1.Sala, O. E. et al. Global biodiversity scenarios for the year 2100. Science 287, 1770–1774 (2000).CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    2.Dudgeon, D. et al. Freshwater biodiversity: Importance, threats, status and conservation challenges. Biol. Rev. 81, 163–182 (2006).PubMed 
    Article 

    Google Scholar 
    3.Strayer, D. L. & Dudgeon, D. Freshwater biodiversity conservation: Recent progress and future challenges. J. N. Am. Benthol. Soc. 29, 344–358 (2010).Article 

    Google Scholar 
    4.Invasive Species Specialist Group IUCN guidelines for the prevention of biodiversity loss caused by alien invasive species. https://portals.iucn.org/library/node/12673 (2000).5.Clavero, M. & García-Berthou, E. Invasive species are a leading cause of animal extinction. Trends Ecol. Evol. 20, 110 (2005).PubMed 
    Article 

    Google Scholar 
    6.Hassan, R., Scholes, R. J. & Ash, N. Ecosystems and human well-being: Current state and trends: Findings of the Condition and Trends working group (Millennium Ecosystem Assessment Series) (Island Press, 2005).7.Vitousek, P. M., D’Antonio, C. M., Loope, L. L., Rejmánek, M. & Westbrooks, R. Introduced species: A significant component of human-caused global change. N. Z. J. Ecol. 21, 1–16 (1997).
    Google Scholar 
    8.Mack, R. N. et al. Biotic invasions: Causes, epidemiology, global consequences, and control. Ecol. Appl. 10, 689–710 (2000).Article 

    Google Scholar 
    9.Hulme, P. E. Beyond control: Wider implications for the management of biological invasions. J. Appl. Ecol. 43, 835–847 (2006).Article 

    Google Scholar 
    10.Vander Zanden, M. J., Hansen, G. J. A., Higgins, S. N. & Kornis, M. S. A pound of prevention, plus a pound of cure: Early detection and eradication of invasive species in the Laurentian Great Lakes. J. Great Lakes Res. 36, 199–205 (2010).Article 

    Google Scholar 
    11.Myers, J. H., Simberloff, D., Kuris, A. M. & Carey, J. R. Eradication revisited: Dealing with exotic species. Trends Ecol. Evol. 15, 316–320 (2000).CAS 
    PubMed 
    Article 

    Google Scholar 
    12.Mehta, S. V., Haight, R. G., Homans, F. R., Polasky, S. & Venette, R. C. Optimal detection and control strategies for invasive species management. Ecol. Econ. 61, 237–245 (2007).Article 

    Google Scholar 
    13.McDonald, L. L. Sampling rare populations. In Sampling Rare or Elusive Species (ed. Thompson, W. L.) 11–42 (Island Press, 2004).
    Google Scholar 
    14.Harvey, C. T., Qureshi, S. A. & MacIsaac, H. J. Detection of a colonizing, aquatic, non-indigenous species. Divers. Distrib. 15, 429–437 (2009).Article 

    Google Scholar 
    15.Ficetola, G. F., Miaud, C., Pompanon, F. & Taberlet, P. Species detection using environmental DNA from water samples. Biol. Lett. 4, 423–425 (2008).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    16.Jerde, C. L., Mahon, A. R., Chadderton, W. L. & Lodge, D. M. “Sight-unseen” detection of rare aquatic species using environmental DNA. Conserv. Lett. 4, 150–157 (2011).Article 

    Google Scholar 
    17.Valentini, A., Pompanon, F. & Taberlet, P. DNA barcoding for ecologists. Trends Ecol. Evol. 24, 110–117 (2009).PubMed 
    Article 

    Google Scholar 
    18.Thomsen, P. F. & Willerslev, E. Environmental DNA—An emerging tool in conservation for monitoring past and present biodiversity. Biol. Conserv. 183, 4–18 (2015).Article 

    Google Scholar 
    19.Rees, H. C., Maddison, B. C., Middleditch, D. J., Patmore, J. R. M. & Gough, K. C. The detection of aquatic animal species using environmental DNA—A review of eDNA as a survey tool in ecology. J. Appl. Ecol. 51, 1450–1459 (2014).CAS 
    Article 

    Google Scholar 
    20.Brys, R. et al. Monitoring of spatio-temporal occupancy patterns of fish and amphibian species in a lentic aquatic system using environmental DNA. Mol. Ecol. https://doi.org/10.1111/mec.15742 (2021).Article 

    Google Scholar 
    21.Smart, A. S. et al. Assessing the cost-efficiency of environmental DNA sampling. Methods Ecol. Evol. 7, 1291–1298 (2016).Article 

    Google Scholar 
    22.Wilcox, T. M. et al. Understanding environmental DNA detection probabilities: A case study using a stream-dwelling char Salvelinus fontinalis. Biol. Conserv. 194, 209–216 (2016).Article 

    Google Scholar 
    23.Dejean, T. et al. Improved detection of an alien invasive species through environmental DNA barcoding: The example of the American bullfrog Lithobates catesbeianus. J. Appl. Ecol. 49, 953–959 (2012).Article 

    Google Scholar 
    24.Bohmann, K. et al. Environmental DNA for wildlife biology and biodiversity monitoring. Trends Ecol. Evol. 29, 358–367 (2014).PubMed 
    Article 

    Google Scholar 
    25.Furlan, E. M., Gleeson, D., Hardy, C. M. & Duncan, R. P. A framework for estimating the sensitivity of eDNA surveys. Mol. Ecol. Resour. 16, 641–654 (2016).CAS 
    PubMed 
    Article 

    Google Scholar 
    26.Cristescu, M. E. & Hebert, P. D. N. Uses and misuses of environmental DNA in biodiversity science and conservation. Annu. Rev. Ecol. Evol. Syst. 49, 209–230 (2018).Article 

    Google Scholar 
    27.Sepulveda, A. J., Nelson, N. M., Jerde, C. L. & Luikart, G. Are environmental DNA methods ready for aquatic invasive species management?. Trends Ecol. Evol. 35, 668–678 (2020).PubMed 
    Article 

    Google Scholar 
    28.Wilcox, T. M. et al. Robust detection of rare species using environmental DNA: The importance of primer specificity. PLoS One 8, e59520. https://doi.org/10.1371/journal.pone.0059520 (2013).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    29.Freeland, J. The importance of molecular markers and primer design when characterizing biodiversity from environmental DNA (eDNA). Genome 60, 358–374 (2016).PubMed 
    Article 
    CAS 

    Google Scholar 
    30.Goldberg, C. S. et al. Critical considerations for the application of environmental DNA methods to detect aquatic species. Methods Ecol. Evol. 7, 1299–1307 (2016).Article 

    Google Scholar 
    31.Veldhoen, N. et al. Implementation of novel design features for qPCR-based eDNA assessment. PLoS One 11, e0164907. https://doi.org/10.1371/journal.pone.0164907 (2016).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    32.Lin, M., Zhang, S. & Yao, M. Effective detection of environmental DNA from the invasive American bullfrog. Biol. Invasions 21, 2255–2268 (2019).Article 

    Google Scholar 
    33.Thalinger, B. et al. A validation scale to determine the readiness of environmental DNA assays for routine species monitoring. Environ. DNA https://doi.org/10.1002/edn3.189 (2021).Article 

    Google Scholar 
    34.Yates, M. C., Fraser, D. J. & Derry, A. M. Meta-analysis supports further refinement of eDNA for monitoring aquatic species-specific abundance in nature. Environ. DNA 1, 5–13 (2019).Article 

    Google Scholar 
    35.Hindson, B. J. et al. High-throughput droplet digital PCR system for absolute quantitation of DNA copy number. Anal. Chem. 83, 8604–8610 (2011).CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    36.Nathan, L. M., Simmons, M., Wegleitner, B. J., Jerde, C. L. & Mahon, A. R. Quantifying environmental DNA signals for aquatic invasive species across multiple detection platforms. Environ. Sci. Technol. 48, 12800–12806 (2014).ADS 
    CAS 
    PubMed 
    Article 

    Google Scholar 
    37.Doi, H. et al. Use of droplet digital PCR for estimation of fish abundance and biomass in environmental DNA surveys. PLoS One 10, e0122763. https://doi.org/10.1371/journal.pone.0122763 (2015).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    38.Brys, R. et al. Reliable eDNA detection and quantification of the European weather loach (Misgurnus fossilis). J. Fish Biol. https://doi.org/10.1111/jfb.14315 (2020).Article 
    PubMed 

    Google Scholar 
    39.Lacoursière-Roussel, A., Côté, G., Leclerc, V. & Bernatchez, L. Quantifying relative fish abundance with eDNA: A promising tool for fisheries management. J. Appl. Ecol. 53, 1148–1157 (2016).Article 
    CAS 

    Google Scholar 
    40.Doi, H. et al. Environmental DNA analysis for estimating the abundance and biomass of stream fish. Freshw. Biol. 62, 30–39 (2017).CAS 
    Article 

    Google Scholar 
    41.Buxton, A. S., Groombridge, J. J., Zakaria, N. B. & Griffiths, R. A. Seasonal variation in environmental DNA in relation to population size and environmental factors. Sci. Rep. 7, 46294. https://doi.org/10.1038/srep46294 (2017).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    42.Takahara, T., Iwai, N., Yasumiba, K. & Takeshi, I. Comparison of the detection of 3 endangered frog species by eDNA and acoustic surveys across 3 seasons. Freshw. Sci. 39, 18–27 (2020).Article 

    Google Scholar 
    43.Kats, L. B. & Ferrer, R. P. Alien predators and amphibian declines: Review of two decades of science and the transition to conservation. Divers. Distrib. 9, 99–110 (2003).Article 

    Google Scholar 
    44.Martel, A. et al. The novel ‘Candidatus Amphibiichlamydia ranarum’ is highly prevalent in invasive exotic bullfrogs (Lithobates catesbeianus). Environ. Microbiol. Rep. 5, 105–108 (2012).PubMed 
    Article 

    Google Scholar 
    45.Blaustein, A. R. et al. Effects of invasive larval bullfrogs (Rana catesbeiana) on disease transmission, growth and survival in the larvae of native amphibians. Biol. Invasions 22, 1771–1784 (2020).Article 

    Google Scholar 
    46.Lowe, S., Browne, M., Boudjelas, S. & De Poorter, M. 100 of the world’s worst invasive alien species. A selection from the Global Invasive Species Database. Published by The Invasive Species Specialist Group (ISSG) a specialist group of the Species Survival Commission (SSC) of the World Conservation Union (IUCN), First published as special lift-out in Aliens 12 (2000).47.Adams, M. J. & Pearl, C. A. Problems and opportunities managing invasive bullfrogs: Is there any hope? In Biological Invaders in Waters: Profiles, Distribution and Threats (ed. Gherardi, F.) 679–693 (Springer, Paris, 2007).
    Google Scholar 
    48.Louette, G., Devisscher, S. & Adriaens, T. Combating adult invasive American bullfrog Lithobates catesbeianus. Eur. J. Wildl. Res. 60, 703–706 (2014).Article 

    Google Scholar 
    49.Kamoroff, C. et al. Effective removal of the American bullfrog (Lithobates catesbeianus) on a landscape level: Long term monitoring and removal efforts in Yosemite Valley, Yosemite National Park. Biol Invasions 22, 617–626 (2020).Article 

    Google Scholar 
    50.Jooris, R. Palmt de stierkikker uit Noord-Amerika ook Vlaanderen in?. Natuur. Focus 1, 13–15 (2001).
    Google Scholar 
    51.Adriaens, T., Devisscher, S. & Louette, G. Risk analysis of American bullfrog, Lithobates catesbeianus. Risk analysis report of non-native organisms in Belgium. Rapporten van het Instituut voor Natuur- en Bosonderzoek 41. https://doi.org/10.13140/2.1.2431.5688 (2013).52.Descamps, S. & De Vocht, A. Movements and habitat use of the invasive species Lithobates catesbeianus in the valley of the Grote Nete (Belgium). Belg. J. Zool. 146, 90–100 (2016).
    Google Scholar 
    53.Strickler, K. M., Fremier, A. K. & Goldberg, C. S. Quantifying effects of UV-B, temperature, and pH on eDNA degradation in aquatic microcosms. Biol. Conserv. 183, 85–92 (2015).Article 

    Google Scholar 
    54.Lefever, S., Pattyn, F., Hellemans, J. & Vandesompele, J. Single-nucleotide polymorphisms and other mismatches reduce performance of quantitative PCR assays. Clin. Chem. 59, 1470–1480 (2013).CAS 
    PubMed 
    Article 

    Google Scholar 
    55.Erligh, H. A., Gelfand, D. & Sninsky, J. J. Recent advances in the polymerase chain reaction. Science 252, 1643–1651 (1991).ADS 
    Article 

    Google Scholar 
    56.Schrader, C., Schielke, A., Ellerbroek, L. & Johne, R. PCR inhibitors—Occurrence, properties and removal. J. Appl. Microbiol. 113, 1014–1026 (2012).CAS 
    PubMed 
    Article 

    Google Scholar 
    57.Lievens, A., Jacchia, S., Kagkli, D., Savini, C. & Querci, M. Measuring digital PCR quality: Performance parameters and their optimization. PLoS One 11, e0153317. https://doi.org/10.1371/journal.pone.0153317 (2016).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    58.Pecoraro, S. et al. Overview and recommendations for the application of digital PCR. EUR 29673 EN, Publications Office of the European Union. https://doi.org/10.2760/192883 (2019).59.Harper, L. R. et al. Prospects and challenges of environmental DNA (eDNA) monitoring in freshwater ponds. Hydrobiologia 826, 25–41 (2019).CAS 
    Article 

    Google Scholar 
    60.Doi, H. et al. Droplet digital PCR outperforms real-time PCR in the detection of environmental DNA from an invasive fish species. Environ. Sci. Technol. 49, 5601–5608 (2015).ADS 
    CAS 
    PubMed 
    Article 

    Google Scholar 
    61.Wells, K. D. (ed.) The Ecology and Behavior of Amphibians (The University of Chicago Press, 2007).
    Google Scholar 
    62.Willis, Y. L., Moyle, D. I. & Baskett, T. S. Emergence, breeding, hibernation, movements and transformation of the bullfrog, Rana catesbeiana Missouri. Copeia 1, 30–41 (1956).Article 

    Google Scholar 
    63.Maruyama, A., Nakamura, K., Yamanaka, H., Kondoh, M. & Minamoto, T. The release rate of environmental DNA from juvenile and adult fish. PLoS One 9, e114639. https://doi.org/10.1371/journal.pone.0114639 (2014).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    64.Barnes, M. A. et al. Environmental conditions influence eDNA persistence in aquatic systems. Environ. Sci. Technol. 48, 1819–1827 (2014).ADS 
    CAS 
    PubMed 
    Article 

    Google Scholar 
    65.Lance, R. F. et al. Experimental observations on the decay of environmental DNA from bighead and silver carps. Manag. Biol. Invasions 8, 343–359 (2017).Article 

    Google Scholar 
    66.Hoorfar, J. Practical considerations in design of internal amplification controls for diagnostic PCR assays. J. Clin. Microbiol. 42, 1863–1868 (2004).CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    67.Devisscher, S. et al. Beheer van de stierkikker in Vlaanderen en Nederland. Rapporten van het Instituut voor Natuur- en Bosonderzoek 52. https://www.researchgate.net/publication/235789235 (2012).68.Bylemans, J. et al. An environmental DNA-based method for monitoring spawning activity: A case study using the endangered Macquarie perch (Macquaria australasica). Methods Ecol. Evol. 8, 646–655 (2017).Article 

    Google Scholar 
    69.Dunn, N., Priestley, V., Herraiz, A., Arnold, R. & Savolainen, V. Behavior and season affect crayfish detection and density inference using environmental DNA. Ecol. Evol. 7, 7777–7785 (2017).PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    70.Bury, R. B. & Whelan, J. A. Ecology and management of the bullfrog. U.S. Fish and Wildlife Service 155 (1984).71.Gahl, M. K., Calhoun, A. J. K. & Graves, R. Facultative use of seasonal pools by American bullfrogs (Rana catesbeiana). Wetlands 29, 697–703 (2009).Article 

    Google Scholar 
    72.Biek, R., Funk, C., Maxell, B. A. & Mills, L. S. What is missing in amphibian decline research: Insights from ecological sensitivity analysis. Conserv. Biol. 16, 728–734 (2002).Article 

    Google Scholar 
    73.Govindarajulu, P., Altwegg, R. & Anholt, B. R. Matrix model investigation of invasive species control: Bullfrogs on Vancouver Island. Ecol. Appl. 15, 2161–2170 (2005).Article 

    Google Scholar 
    74.Carim, K. J. et al. Environmental DNA sampling informs fish eradication efforts: Case studies and lessons learned. N. Am. J. Fish. 40, 488–508 (2020).Article 

    Google Scholar 
    75.Riaz, T. et al. ecoPrimers: Inference of new DNA barcode markers from whole genome sequence analysis. Nucleic Acids Res. 39, e145. https://doi.org/10.1093/nar/gkr732 (2011).CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    76.Moyer, G. R., Díaz-Ferguson, E., Hill, J. E. & Shea, C. Assessing environmental DNA detection in controlled lentic systems. PLoS One 9, e103767. https://doi.org/10.1371/journal.pone.0103767 (2014).ADS 
    CAS 
    Article 
    PubMed 
    PubMed Central 

    Google Scholar 
    77.Turner, C. R. et al. Particle size distribution and optimal capture of aqueous macrobial eDNA. Methods Ecol. Evol. 7, 676–684 (2014).Article 

    Google Scholar 
    78.U.S. Fish and Wildlife Service. Quality assurance project plan: eDNA monitoring of bighead and silver carps. https://www.fws.gov/midwest/fisheries/eDNA/documents/QAPP.pdf (2017).79.Spens, J. et al. Comparison of capture and storage methods for aqueous macrobial eDNA using an optimized extraction protocol: Advantage of enclosed filter. Methods Ecol. Evol. 8, 635–645 (2017).Article 

    Google Scholar 
    80.RStudio Team (2020) RStudio: Integrated Development Environment for R. RStudio, PBC. http://www.rstudio.com/. More

  • in

    Retrospective methodology to estimate daily infections from deaths (REMEDID) in COVID-19: the Spain case study

    COVID-19 vs. MoMoThe COVID-19 official deaths and MoMo ED time series overlaped for the period from 3 March 2020 to 1 January 2021 for Spain and its 19 regions (Fig. 2). In general, there was good agreement between both datasets, meaning that most of MoMo ED were related to COVID-19 deaths. During the first wave, the most important differences were observed in Spain, Madrid, Cataluña, Castilla-La Mancha, and Castilla y León. Before 22 June in Spain, MoMo ED showed 15,445 accumulated deaths more than the official COVID-19 deaths, which is beyond the error band. That difference comes basically from the four regions with the largest numbers of deaths (Madrid, Cataluña, Castilla-La Mancha, and Castilla y León). Table 1 shows the accumulated values before 22 June, which were used to estimate the CFR for Spain and its 19 regions according to the third phase of the National Seroprevalence Study4,5. For all regions, the CFR estimated from MoMo ED was larger than the CFR estimated from COVID-19 deaths. In particular, Asturias, Canarias, and Murcia were twice as large. Ceuta and Melilla dramatically increased their CFR from MoMo ED, although that may be biased due to their small populations and numbers of deaths.Similarly, the same variables for the period from 23 June to 29 November 2020 are reported in Table 2. In Spain, MoMo ED showed 6173 accumulated deaths more than the official COVID-19 deaths. This difference is a third of the difference observed prior to 22 June; because this is within the error band, there was a significant improvement in the detection of COVID-19 deaths in this period. Figure 2 also shows a general agreement between MoMo ED and official COVID-19 deaths time series after the first wave, with the exception of late July and early August. These differences were due to two heat waves that were responsible for at least 25% of the MoMo ED16.Infections estimated from COVID-19 deathsTo illustrate the delay between official daily infections data and REMEDID estimated daily infections, we applied REMEDID from COVID-19 deaths assuming CFR = 100%. Figure 3 shows the current IO21 and the infections associated with COVID-19 deaths for the first wave. The latter in Spain reached a maximum on 13 March 2020 (Table 3), the day before the national government decreed a state of emergency and national lockdown. Thus, the adopted measures had an immediate effect, which was observed in the official data IO21 7 days later (20 March). This delay is similar to the incubation period (mean 5.78 days2), which could be explained because official infections were reported when symptoms appeared. This delay reached 16 days when we compared with earlier version IO20 (not shown), which highlights the usefulness of the methodology to reinterpret official data from very early stages of the pandemic. On the other hand, the maximum number of deaths was reached on 1 April, which was 19 days after the inferred infection maximum, bringing this delay close to the 20 days expected between infection and death (Figs. 1, 3).Figure 3Official COVID-19 infections and deaths, and estimated infections with case fatality ratio (CFR) of 100% in Spain during the first wave. Left y-axis: COVID-19 daily infections IO21 (blue curve). Right y-axis: COVID-19 deaths (orange curve) and its REMEDID-estimated infections with CFR = 100% (red curve). All curves are for Spain. Thin blue and orange curves are daily data, and thick curves are smoothed by 14-day running mean. Arrows show delays between the maximum of inferred infections and maxima from COVID-19 deaths (orange arrows) and COVID-19 infections (blue arrows). Solid arrows are expected delays, dotted while arrows are observed delays.Full size imageTable 3 Date of first infection for REMEDID estimated daily infections from COVID-19 deaths (IRO) and from MoMo Excess Deaths (ED) (IRM), and for official COVID-19 daily infections released on June 2020 (IO20) and on February 2021 (IO21).Full size tableWe applied REMEDID to the official COVID-19 deaths with the corresponding estimated CFRs (see “Data” section) to obtain the time series of estimated daily infections, hereafter referred to as IRO. Figure 4 shows IRO and the accumulated infections for Spain and its 19 regions. Note that in Spain, IRO are amplified versions of inferred infections in Fig. 3. In Spain, the first infection, according to IRO,, is on 8 January 2020 (Table 3), 43 days before the first infection was officially reported on 20 February 2020 according to IO20. By contrast, IO21 places the first infection on 1 January 2020. Spain reached the maximum number of IRO on 13 March, a day before the state of emergency and lockdown were enforced (Table 4). On 14 March, IO20 = 1832, and IO21 = 7478; however, IRO = 63,727 (CI 95% 60,050–67,403), 35 and 9 times IO20 and IO21, respectively (Table 5). This implies that on that day, IO20 and IO21 only reported 2.9% (CI 95% 2.7–3.1%) and 11.7% (CI 95% 11.1–12.5%) of new infections, respectively. Although detection of infections clearly improved from IO20 to IO21, almost 90% of the infections are still not documented in the peak of the first wave. The situation is similar for the accumulated infections before 22 June 2020, as reported by the National Seroprevalence Study4,5.Figure 4Daily and accumulated infections for official COVID-19 daily infections (IO21), and daily infections estimated from COVID-19 deaths (IRO). Lines are daily infections and refer to the y-axis on the right; bars are accumulated infections and refer to the y-axis on the left. Red lines and cyan bars are official COVID-19 data; orange lines and blue bars are inferred infections with case fatality ratio (CFR) in Table 1. Thin orange lines correspond to the CFR confidence interval.Full size imageTable 4 Date of the most prominent relative maxima, for Spain and the 19 regions, of the REMEDID estimated daily infections from COVID-19 deaths (IRO) and from MoMo excess deaths (ED) (IRM), and official COVID-19 daily infections (IO21).Full size tableTable 5 REMEDID estimated daily infections from COVID-19 deaths (IRO) and from MoMo excess deaths (ED) (IRM) on 14 March, and for official COVID-19 daily infections released on June 2020 (IO20) and released on February 2021 (IO21).Full size tableIn almost all regions, IO20 showed a delay of 1 month or more between the first infection and IRO (Table 3). No delay in IO21 occurred in Islas Baleares, Castilla-León, and Galicia, while in three regions (Cataluña, Madrid, and La Rioja), the first case occurred earlier than the first case of IRO. However, 6 regions had delays of 15 days and other 6 regions had delays of 1 month. According to IRO, all regions except Ceuta and Melilla had some infections in January, but in IO21 only 6 regions had infections in that month. In all scenarios, the first infections were in Madrid and Cataluña.During the first wave, according to IRO most of the regions had maximum daily infections around 14 March. In Madrid, the maximum was reached on 11 March, coinciding with the educational centres closing and an official warning by the regional government (Table 4). Asturias was the last region to reach peak infections (25–26 March). The maximum percentage of documented cases (12.6%, CI 95% 9.2–18.4%) occurred in Asturias on 14 March, but in the other regions, only between 1.2 and 8% of the infections were documented (Table 5).Figure 4 shows how the IO21 and IRO curves of Spain and the 19 different regions fluctuated following the same pattern until the middle of June 2020, but thereafter, they showed different patterns. This reflects the fact that the Spanish government had decreed the control measures for the whole nation until June, but thereafter, each regional government implemented its own control measures. For example, some regions (e.g., Aragón, Islas Baleares, Cantabria, Comunidad Valenciana, Extremadura, Galicia, Murcia, País Vasco, and La Rioja) had two peaks, but others had only one. An apparent maximum on 22 June in Islas Baleares is an artifact produced by the interpolation for transition from the two CFRs. Although beyond the scope of this work, it would be very interesting to investigate the effects of the different control measures implemented on the corresponding IRO for the 19 regions.The Spanish COVID-19s wave reached a maximum of daily infections on 22 October from IRO and on 26 October from IO21. The delay of 4 days is similar to the mean incubation period (5.78 days2). The estimated number of new infections is still larger than the documented cases, but the shapes of the two curves are more similar in the second wave than in the first wave (Fig. S1). The same is true for the 19 regions, most of which had the largest peak around 22–26 October, with the exceptions of Canarias and Madrid, which reached maxima in late August and early September, respectively.Infections from MoMo excess deathsAssuming that MoMo ED accounts for both recorded and non-recorded COVID-19 deaths, negative deaths are meaningless, and they were set to zero. Then, the associated daily infections can be estimated, as in “Infections estimated from COVID-19 deaths” section, with a CFR of 100% from MoMo ED for Spain (Fig. 5). Note two main differences between this time series and that estimated from official COVID-19 deaths: (1) MoMo data present an error band that was inherited by the estimated infections; (2) MoMo ED estimated infections reached a maximum of 1443 (CI 99% 1329–1547), doubling the 776 inferred daily infections from official COVID-19 deaths in Fig. 3. This is because maximum MoMo ED was 1,584 (CI 99% 1468–1686) and maximum COVID-19 official deaths was 828, both estimated from the 14-day running mean time series. The maximum of inferred infections was reached on 13 March, just one day prior to the state of emergency and lockdown. The expected and observed delays with respect to official infections and MoMo ED were similar to those observed for estimated infections from official COVID-19 deaths. Error bounds of the estimated infections in Fig. 5 were computed from the MoMo ED error bounds. However, it should be highlighted that the combination of the error bounds from MoMo ED and the estimated CFRs might lead to unrealistic error estimates. To avoid this, the error estimates in Fig. 6 were estimated from the MoMo ED time series (no error bounds) and the error bounds of the estimated CFRs.Figure 5Official COVID-19 infections, MoMo Excess Deaths (ED), and estimated infections with case fatality ratio (CFR) of 100% in Spain during the first wave. Left y-axis: COVID-19 daily infections IO21 (blue curve). Right y-axis: MoMo ED (orange curve) and its REMEDID-estimated infections with CFR = 100% (red curve). All curves are for Spain. Thin blue and orange curves are daily data, and thick curves are smoothed by 14-days running mean. Dashed curves represent the error estimate of MoMo ED (orange) and inferred infections (red). Arrows show delays between the maximum of inferred infections and maxima from MoMo ED (orange arrows) and COVID-19 infections (blue arrows). Solid arrows are expected delays, dotted while arrows are observed delays.Full size imageFigure 6Daily and accumulated infections for official COVID-19 daily infections (IO21), and daily infections estimated from MoMo Excess Deaths (ED) (IRM). Lines are daily infections and refer to the y-axis on the right; and bars are accumulated infections and refer to the y-axis on the left. Red lines and cyan bars are for official COVID-19 data; and orange lines and blue bars are for inferred infections with case fatality ratio (CFR) in Table 1. Thin orange lines represent the error estimate of inferred infections.Full size imageThe REMEDID was applied to the MoMo ED with the corresponding CFRs (see “Data” section) to obtain the estimated daily infections, which will be referred hereafter as IRM. The IRM were calculated for Spain and its 19 regions and are depicted in Fig. 6, as well as the accumulated IRM. In Spain, the first infection shown by IRM happened on 9 January, with an error estimate from 9 to 10 January, 41 to 42 days before the first documented infection of IO20 on 20 February 2020 (Table 3). The maximum IRM was 77,855 (CI 95% 73,364–82,347) reached on 13 March. On 14 March, IRM showed 14,128 infections more than IRO (Table 5). Notice that the CFR used with MoMo ED data was larger than the one used with official COVID-19 deaths data, which makes this difference even more remarkable, because the larger the CFR the lower the estimated infections. Therefore, if the true CFRs, which are unknown, were used in both cases, IRM would double IRO on 14 March, as happened when a CFR of 100% was used (Figs. 3, 5). Notice that with the CFRs used, the IRM and IRO resulted in the same accumulated infections on 22 June and 29 November, matching the results of the seroprevalence study. Nevertheless, IRM showed 42 times more cases than IO20 and 10 times more than IO21 on 14 March, detection of official cases of only 2.4% (2.2–2.5%) and 9.6% (9.1–10.2%), respectively.Table 3 shows the estimated date of first infection for Spain and by region. Note that the first cases of IRM in Spain were on 9 January and in Aragón, Canarias, and Navarra on 8 January, which is possible because significant excess deaths in a region may not become significant for the whole country. In general, the maxima of daily infections were closer to those on 14 March in IRM than in IRO. During the first wave, all regions showed a single maximum, except for Ceuta, Melilla, and Murcia, which showed two maxima (Fig. 6). In general, the IRM time series in all regions were similar during that period. The official data clearly under-detected infections during the first wave. On 14 March, IRM were comparable to IRO, overlapping CI in all regions, but not in Spain as a whole (Table 5). During the second wave, there was improved detection of cases with differences among regions. More

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    Fungal diversity driven by bark features affects phorophyte preference in epiphytic orchids from southern China

    Study site and speciesThe sub-tropical forest analysed in this study is located in China, Yunnan, Xishuangbanna, Mengla county, Village Quingyanzhai (#94) N 21.802068, E 101.380214, geodetic datum WGS84 (Fig. 6). The site is characterized by a rocky outcrop rising 30–50 m over surrounding rubber plantations, harbouring about 20 ha of relict dry tropical forest. The outcrop sides are steep and mainly covered with bamboo. The top area is colonized by shrubs and 10–15 m high trees (a few trees on the slopes are much higher). The most conspicuous species is Quercus yiwuensis Y.C. Hsu & H.W. Jen. In March 2017 we selected four individual trees of Q. yiwuensis, and an equal number of Pistacia weinmannifolia Franch, and Beilschmiedia percoriacea C.K. Allen that were also numerous on the site. Plants were identified by the authors in the field and labelled. Botanical specimens were deposited in the School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China.Figure 6Map of the study site with approximate position of analysed trees (aerial perspective from Google Maps 2018). GPS positions were obtained less than 1 m from the tree trunks. The distance from N3 to B1 is approximately 60 m.Full size imageQ. yiwuensis was designated P-tree (P1, P2, P3, P4) because we consistently found the orchid Panisea uniflora Lindl. growing on this phorophyte species. P. weinmannifolia was designated B-tree (B1, B2, B3, B4) because it harboured the orchid species Bulbophyllum odoratissimum (Sw) Lindl. (Supplementary Fig. S2 a-d). On P. weinmannifolia trees no P. uniflora was observed, while B. odoratissimum was never found on Q. yiwuensis trees. Both tree species were richly colonized by several other orchid species. Beilschmiedia percoriacea trees were designated neutral tree, N-tree (N1, N2, N3, N4), because neither of the two target orchid species grew on them. The latter tree species carried several lichens and a single fern species (Lepisorus sp.), but only in one instance was observed to carry an orchid epiphyte (Coelogyne sp.).GPS positions of investigated trees were obtained less than 1 m from the trunk (Fig. 6). Accuracy is about 3 m. Accuracy in altitude readings is about 100 m. Distance between degrees of latitude is 111 km. At N 21.78978 the distance between degrees of longitude is 103 km, which means that the last digit in the 5-digit decimal degrees corresponds to 1.11 m in latitude and 1.03 m in longitude.The trees were labelled with different colours as follows:

    P-trees (carrying P. uniflora and other epiphytes, but not B. odoratissimum), identified as Q. yiwuensis, with red labels (P1 N 21.79880, E 101.37909, 1073; P2 N 21.79882, E 101.37923, 1072; P3 N 21.79878, E 101.37947, 1074; P4 N 21.79878, E 101.37904, 1073).

    B-trees (carrying B. odoratissimum and other epiphytes, but not P. uniflora), identified as P. weinmannifolia, with blue labels (B1 N 21.79878, E 101.37950, 1074; B2 N 21.79880, E 101.37938, 1078; B3 N 21.79881, E 101.37931, 1083; B4 N 21.79884, E 101.37923, 1076).

    N-trees (carrying epiphytes, but neither B. odoratissimum nor P. uniflora), identified as B. percoriacea, with yellow labels (N1 N 21.79873, E 101.37905, 1064; N2 N 21.79868, E 101.37908, 1072; N3 N 21.79883, E 101.37893, 1071; N4 N 21.79879, E 101.37895, 1071).

    The point of access to the outcrop top area was located at the Western edge (N 21.79880, E 101.37827, 1058, Fig. 6).

    SamplingFor each of the twelve selected trees, breast height circumference (BH = 130 cm above ground) was measured. Approximate total height was determined by Nikon Laser Forestry Pro or estimated if sighting lines were interfered by other vegetation.The lowermost individual of the target orchid species was recorded in relation to BH. Bark samples were collected, and bark features recorded at BH, by target orchid, and 50 cm above target orchid or BH, whichever was highest point. In N-trees, where there were no target orchids, sampling was thus at BH, BH + 50 cm, and BH + 100 cm.Sampling on each tree involved approximately 12 cm2 bark cut out with a sterile knife and rubber gloves to prevent cross-contamination, for pH-analysis, metabarcoding, fungal isolation and chemical analysis. Besides, 3 bark cores were taken by trephor sampler (16 mm, 2 mm diam., Costruzioni Meccaniche Carabin Carlo) for water holding measurement.Roots of target orchids were sampled, from three adult individual plants on each P- and B-tree. No permissions were necessary to collect plant samples, using a protocol that avoided plant damages. All plants were left in the exact location where they were found in the sampling site, after collecting the small portions of bark and root material for the study. All experiments including the collection of plant material in this study are in compliance with relevant institutional, national, and international guidelines and legislation.All fresh material collected from the sampling site was first kept in cool boxes, brought to the laboratory, and processed within three days.Fungal isolation from barkFor each sample, half of the bark material and orchid roots were kept at − 80 °C for subsequent metabarcoding analysis. The rest of bark (about 2 g for each sample) was immediately processed for fungal isolation. The large bark portions were ground into powder using a sterile mortar and pestle; 5 ml were reserved for pH measurement, while the rest was suspended in a final volume 50 ml sterile water solution in a sterile centrifuge tube. The tube was shaken with Vortex vibration meter thoroughly and solution aliquots were spread homogenously onto isolation medium plates. For each bark sample, aliquots of 500, 300, 200, and 100 μl, were spread per triplicate to one plate each of PDA (Potato Dextrose Agar) medium, containing ampicillin (50 μg/mL) and streptomycin (50 μg/ml) to inhibit bacterial growth49,50. A diluted solution was also made by mixing 1 ml of the original solution with 9 ml sterile water and plated. Petri dishes were incubated at room temperature (23–25 °C) in the dark for up to 2 months to allow the development of slow-growing mycelia. Fast growing fungal strains started to grow after about two days. Colonies showing different morphology and appearance were transferred to fresh plates to obtain pure cultures. In the following days, other slower growing mycelia were available in the Petri dishes and were also regularly picked up and isolated onto new PDA plates every 2 days. All isolated fungal strains were stored at 4 °C for further analysis. All strains were deposited in the LP Culture Collection (personal culture collection held in the laboratory of Prof. Lorenzo Pecoraro), at the School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China.Molecular and morphological analysis of bark culturable fungiThe identification of isolated fungal colonies was performed using DNA sequencing combined with microscopy. Total genomic DNA from isolated fungi was extracted following the cetyltrimethyl ammonium bromide (CTAB) method modified from Doyle and Doyle51. Fungal ITS regions were PCR-amplified using the primer pair ITS1F/ITS452 following the procedure described in Pecoraro et al.37 for PCR reaction, thermal cycling, and purification of PCR products. Controls with no DNA were included in every amplification experiment in order to test for the presence of laboratory contamination from reagents and reaction buffers. Purified DNA amplicons were sequenced with the same primer pair used for amplification. DNA sequencing was performed at the GENEWIZ Company, Tianjin, China.Sequences were edited to remove vector sequences and to ensure correct orientation and assembled using Sequencher 4.1 for MacOsX (Genes Codes, Ann Arbor, MI). Sequence analysis was conducted with BLAST searches against the National Center for Biotechnology Information (NCBI) sequence database (GenBank; http://www.ncbi.nlm.nih. gov/BLAST/index.html) to determine the closest sequence matches that enabled taxonomic identification. DNA sequences were deposited in GenBank (Accession Nos. MW603206 – MW603451). Fungal morphological characters (hyphae, pseudohyphae, conidiophores, conidia, poroconidia, arthroconidia, etc.) were examined using a Nikon ECLIPSE Ci microscope for the identification of isolates following the standard taxonomic keys53,54,55,56,57.Assessment of bark and orchid associated fungal community using Illumina sequencingBark and orchid root samples were pulverized in a sterile mortar, and genomic DNA was extracted using the FastDNA® Spin Kit as described by the manufacturer (MP Biomedicals, Solon, OH, USA)58,59. In total, this resulted in 60 DNA samples, including 36 from bark (3 sampling points for each tree × 12 trees) and 24 from orchid roots (3 orchid individuals sampled on each P- and B-tree × 8 trees; the 4 individual N-trees were not used for orchid sampling because they did not carry the study orchid species). Subsequently, amplicon libraries were created using two primer combinations targeting the internal transcribed spacer 2 (ITS-2): ITS7F and ITS4R60 was used as universal fungal primer pair to target nearly all fungal species, while ITS361 and ITS4OF62 was used to more specifically target orchid mycorrhizal fungi. Previous research has shown that most universal fungal primers have multiple mismatches to many species of the orchid-associating basidiomycetes, in particular in Tulasnellaceae family46,58,63. Since the goal of the present work was to analyse the total fungal community in the orchid-phorophyte environment (bark and orchid roots), as well as more specifically detect the orchid mycorrhizal fungi in the studied samples, it was necessary to combine two different primer pairs to characterise the whole investigated fungal diversity47,64,65,66. Polymerase chain reaction (PCR) amplification was performed in 50 μl reaction volume, containing 38 μl steril distilled water, 5 μl 10 × buffer (100 mM Tris–HCl pH 8.3, 500 mM KCl, 11 mM MgCl2, 0.1% gelatin), 1 μl of dNTP mixture of 10 mM concentration, 0.25 μM of each primer, 1.5 U of RED TaqTM DNA polymerase (Sigma) and approximately 10 μg of extracted genomic DNA. PCR conditions were as follows: 1 cycle of 95 °C for 5 min initial denaturation before thermocycling, 30 cycles of 94 °C for 40 s denaturation, 45 s annealing at various temperatures following Taylor and McCormick62, 72 °C for 40 s elongation, followed by 1 cycle of 72 °C for 7 min extension. To minimize PCR bias, three PCRs were pooled for each sample. The resulting PCR products were electrophoresed in 1% agarose gel with ethidium bromide and purified with the QIAEX II Gel Extraction Kit (QIAGEN). Amplicon libraries were generated using the NEB Next Ultra DNA Library Prep Kit for Illumina (New England Biolabs, USA) following the manufacturer’s instructions to add index codes. Samples were sequenced using the Illumina MiSeq PE 250 sequencing platform (Illumina Inc., San Diego, CA) at Shanghai Majorbio Bio‐Pharm Technology Co., Ltd. (Shanghai, China).Bioinformatics of fungal sequencesSequences originated from the total (ITS7F and ITS4R primers) and orchid-associated (ITS3 and ITS4OF primers) fungi datasets were processed separately. Raw reads were merged with a minimum overlap of 30 nucleotides, and the primer sequences were trimmed off. Subsequently, reads were filtered by discarding all sequences with expected error  > 1. The quality-filtered reads were denoised using the UNOISE3 algorithm67 to create zero-radius operational taxonomic units (zOTUs), with chimera removal. All the steps were performed using USEARCH v.1168. Raw sequences have been deposited in the Sequences Read Archive (SRA) of NCBI as BioProject ID PRJNA702612. The fungal zOTUs were assigned to taxonomic groups using the Blast algorithm by querying against the UNITE + INSD fungal ITS database (version 7.2, released on 10 October 2017)69 using the sintax algorithm with 0.8 cutoff70. The zOTUs originated with the orchid-associated fungal primers were manually screened for possible orchid-associated mycorrhizal families based on the information provided in Table 12.1 in Dearnaley et al.71, and only these were retained for further analysis in this dataset.To attempt removing spurious counts due to cross-talk (assignment of reads to a wrong sample) we removed all the zOTUs represented by less than 0.02% of reads in each sample, which is more conservative than previous error estimates72. The datasets were rarefied to the minimum sequencing depth (23,419 for total fungi and 13,074 for orchid-associated fungi), zOTUs present in less than three samples and low abundant zOTUs (with relative abundance  More

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    Enzyme promiscuity in natural environments: alkaline phosphatase in the ocean

    1.Falkowski PG, Fenchel T, Delong EF. The microbial engines that drive Earth’s biogeochemical cycles. Science. 2008;320:1034–9.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    2.Arnosti C. Microbial extracellular enzymes and the marine carbon cycle. Ann Rev Mar Sci. 2011;3:401–25.PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    3.Arnosti C, Bell C, Moorhead DL, Sinsabaugh RL, Steen AD, Stromberger M, et al. Extracellular enzymes in terrestrial, freshwater, and marine environments: perspectives on system variability and common research needs. Biogeochemistry. 2013;117:5–21.Article 
    CAS 

    Google Scholar 
    4.Moorhead DL, Rinkes ZL, Sinsabaugh RL, Weintraub MN. Dynamic relationships between microbial biomass, respiration, inorganic nutrients and enzyme activities: informing enzyme-based decomposition models. Front Microbiol. 2013;4:223.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    5.Li M, Gao Y, Qian W-J, Shi L, Liu Y, Nelson WC, et al. Targeted quantification of functional enzyme dynamics in environmental samples for microbially mediated biogeochemical processes. Environ Microbiol Rep. 2017;9:512–21.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    6.Song H-S, Thomas DG, Stegen JC, Li M, Liu C, Song X, et al. Regulation-structured dynamic metabolic model provides a potential mechanism for delayed enzyme response in denitrification process. Front Microbiol. 2017;8:1866.PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    7.Khersonsky O, Tawfik DS. Enzyme promiscuity: a mechanistic and evolutionary perspective. Annu Rev Biochem. 2010;79:471–505.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    8.Baier F, Copp JN, Tokuriki N. Evolution of enzyme superfamilies: comprehensive exploration of sequence-function relationships. Biochemistry. 2016;55:6375–88.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    9.Sebastián M, Niell FX. Alkaline phosphatase activity in marine oligotrophic environments: implications of single-substrate addition assays for potential activity estimations. Mar Ecol Prog Ser. 2004;277:285–90.Article 

    Google Scholar 
    10.Catrina I, O’Brien PJ, Purcell J, Nikolic-Hughes I, Zalatan JG, et al. Probing the origin of the compromised catalysis of E. coli alkaline phosphatase in its promiscuous sulfatase reaction. J Am Chem Soc. 2007;129:5760–5.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    11.Sunden F, AlSadhan I, Lyubimov AY, Ressl S, Wiersma-Koch H, Borland J, et al. Mechanistic and evolutionary insights from comparative enzymology of phosphomonoesterases and phosphodiesterases across the alkaline phosphatase superfamily. J Am Chem Soc. 2016;138:14273–87.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    12.Yang K, Metcalf WW. A new activity for an old enzyme: Escherichia coli bacterial alkaline phosphatase is a phosphite-dependent hydrogenase. Proc Natl Acad Sci USA. 2004;101:7919–24.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    13.Copley SD. Shining a light on enzyme promiscuity. Curr Opin Struct Biol. 2017;47:167–75.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    14.Steen AD, Vazin JP, Hagen SM, Mulligan KH, Wilhelm SW. Substrate specificity of aquatic extracellular peptidases assessed by competitive inhibition assays using synthetic substrates. Aquat Micro Ecol. 2015;75:271–81.Article 

    Google Scholar 
    15.Ivars-Martínez E, D’Auria G, RodrÍGuez-Valera F, SÁNchez-Porro C, Ventosa A, et al. Biogeography of the ubiquitous marine bacterium Alteromonas macleodii determined by multilocus sequence analysis. Mol Ecol. 2008;17:4092–106.PubMed 
    Article 
    CAS 
    PubMed Central 

    Google Scholar 
    16.Tada Y, Taniguchi A, Nagao I, Miki T, Uematsu M, Tsuda A, et al. Differing growth responses of major phylogenetic groups of marine bacteria to natural phytoplankton blooms in the western North Pacific Ocean. Appl Environ Microbiol. 2011;77:4055–65.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    17.Schubert M, Lindgreen S, Orlando L. AdapterRemoval v2: rapid adapter trimming, identification, and read merging. BMC Res Notes. 2016;9:88.PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    18.Li D, Liu C, Luo R, Sadakane K, Lam T. MEGAHIT: an ultra-fast single-node solution for large and complex metagenomics assembly via succinct de Bruijn graph. Bioinformatics. 2015;31:1674–6.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    19.Hyatt D, Chen GL, Locascio PF, Land ML, Larimer FW, Hauser LJ. Prodigal: prokaryotic gene recognition and translation initiation site identification. BMC Bioinforma. 2010;11:119.Article 
    CAS 

    Google Scholar 
    20.Bushnell B. “BBMap: a fast, accurate, splice-aware aligner,” in Proceedings of the 9th Annual Genomics of Energy & Environment Meeting. Walnut Creek, CA, USA; 2014.21.Scholz J, Besir H, Strasser C, Suppmann S. A new method to customize protein expression vectors for fast, efficient and background free parallel cloning. BMC Biotechnol. 2013;13:12.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    22.McLoughlin SY, Jackson C, Liu JW, Ollis DL. Growth of Escherichia coli coexpressing phosphotriesterase and glycerophosphodiester phosphodiesterase, using paraoxon as the sole phosphorus source. Appl Environ Microbiol. 2004;70:404–12.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    23.Britton J, Dyer RP, Majumdar S, Raston CL, Weiss GA. Ten-minute protein purification and surface tethering for continuous-flow biocatalysis. Angew Chem Int Ed Engl. 2017;56:2296–301.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    24.Ortiz-Tena JG, Rühmann B, Sieber V. Colorimetric determination of sulfate via an enzyme cascade for high-throughput detection of sulfatase activity. Anal Chem. 2018;90:2526–33.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    25.Huitema C, Horsman G. Analyzing enzyme kinetic data using the powerful statistical capabilities of R. 2018. http://biorxiv.org/content/10.1101/316588v1.26.Rainer SF. Soft-bottom benthic communities in Otago Harbour and Blueskin Bay, New Zealand. New Zealand Oceanographic Institute Memoir 80; 1981.27.Grove SL, Probert PK. Sediment macrobenthos of upper Otago Harbour, New Zealand. New Zeal J Mar Fresh. 1999;33:469–80.28.Hoppe HG. Significance of exoenzymatic activities in the ecology of brackish water: measurements by means of methylumbelliferyl-substrates. Mar Ecol Prog Ser. 1983;11:299–308.CAS 
    Article 

    Google Scholar 
    29.Yamaguchi T, Sato M, Hashihama F, Ehama M, Shiozaki T, Takahashi K, et al. Basin‐scale variations in labile dissolved phosphoric monoesters and diesters in the central North Pacific Ocean. J Geophys Res Oceans. 2019;124:3058–72.CAS 
    Article 

    Google Scholar 
    30.Baltar F, Lundin D, Palovaara J, Lekunberri I, Reinthaler T, Herndl GJ, et al. Prokaryotic responses to ammonium and organic carbon reveal alternative CO2 fixation pathways and importance of alkaline phosphatase in the mesopelagic North Atlantic. Front Microbiol. 2016;7:1670.PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    31.Yamaguchi H, Arisaka H, Seki M, Adachi M, Kimura K, Tomaru Y. Phosphotriesterase activity in marine bacteria of the genera Phaeobacter, Ruegeria, and Thalassospira. Int Biodeter Biodegr. 2016;115:186–91.CAS 
    Article 

    Google Scholar 
    32.Davidi D, Noor E, Liebermeister W, Bar-Even A, Flamholz A, Tummler K, et al. Global characterization of in vivo enzyme catalytic rates and their correspondence to in vitro kcat measurements. Proc Natl Acad Sci USA. 2016;113:3401–6.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    33.Paytan A, Cade-Menum BJ, McLaughlin K, Faul KL. Selective phosphorus regeneration of sinking marine particles: evidence from 31P-NMR. Mar Chem. 2003;82:55–70.CAS 
    Article 

    Google Scholar 
    34.Wu J, Wang P, Wang Y. Cytotoxic and mutagenic properties of alkyl phosphotriester lesions in Escherichia coli cells. Nucleic Acids Res. 2018;46:4013–21.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    35.McCarthy JG, Edington BV, Schendel PF. Inducible repair of phosphotriesters in Escherichia coli. Proc Natl Acad Sci USA. 1983;80:7380–4.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    36.Helbert W. Marine polysaccharide sulfatases. Front Mar Sci. 2017;4:6.Article 

    Google Scholar 
    37.Wegner CE, Richter-Heitmann T, Klindworth A, Klockow C, Richter M, Achstetter T, et al. Expression of sulfatases in Rhodopirellula baltica and the diversity of sulfatases in the genus Rhodopirellula. Mar Genomics. 2013;9:51–61.PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    38.Canfield DE, Farquhar J. Animal evolution, bioturbation, and the sulfate concentration of the oceans. Proc Natl Acad Sci USA. 2009;106:8123–7.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    39.Luo HW, Benner R, Long RA, Hu JJ. Subcellular localization of marine bacterial alkaline phosphatases. Proc Nat Acad Sci USA. 2009;106:21219–23.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    40.Wu J-R, Shien J-H, Shieh HK, Hu C-C, Gong S-R, Chen L-Y, et al. Cloning of the gene and characterization of the enzymatic properties of the monomeric alkaline phosphatase (PhoX) from Pasteurella multocida strain X-73. FEMS Microbiol Lett. 2007;267:113–20.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    41.Kageyama H, Tripathi K, Rai AK, Cha-um S, Waditee-Sirisattha R, Takabe T. An alkaline phosphatase/phosphodiesterase, PhoD, induced by salt stress and secreted out of the cells of Aphanothece halophytica, a halotolerant cyanobacterium. Appl Environ Micro. 2011;77:5178–83.CAS 
    Article 

    Google Scholar 
    42.Rodriguez F, Lillington J, Johnson S, Timmel CR, Lea SM, Berks BC. Crystal structure of the Bacillus subtilis phosphodiesterase PhoD reveals an iron and calcium-containing active site. J Biol Chem. 2014;289:30889–99.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    43.Noskova Y, Likhatskaya G, Terentieva N, Son O, Tekutyeva L, Balabanova L. A novel alkaline phosphatase/phosphodiesterase, CamPhoD, from marine bacterium Cobetia amphilecti KMM 296. Mar Drugs. 2019;17:657.CAS 
    PubMed Central 
    Article 

    Google Scholar 
    44.Dyhrman ST, Ammerman JW, Van, Mooy BAS. Microbes and the marine phosphorus cycle. Oceanography. 2007;20:110–6.Article 

    Google Scholar 
    45.Larson TJ, Ehrmann M, Boos W. Periplasmic glycerophosphodiester phosphodiesterase of Escherichia coli, a new enzyme of the glp regulon. J Biol Chem. 1983;258:5428–32.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    46.van Veen HW. Phosphate transport in prokaryotes: molecules, mediators and mechanisms. Antonie Van Leeuwenhoek. 1997;72:299–315.PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    47.Parthasarathy S, Parapatla H, Nandavaram A, Palmer T, Siddavattam D. Organophosphate hydrolase is a lipoprotein and interacts with Pi-specific transport system to facilitate growth of Brevundimonas diminuta using op insecticide as source of phosphate. J Biol Chem. 2016;291:7774–85.CAS 
    PubMed 
    PubMed Central 
    Article 

    Google Scholar 
    48.Hong T, Kong A, Lam J, Young L. Periplasmic alkaline phosphatase activity and abundance in Escherichia coli B23 and C29 during exponential and stationary phase. J Exp Microbiol Immunol. 2007;11:8–13.
    Google Scholar 
    49.Baltar F, Arístegui J, Gasol J, Yokokawa T, Herndl GJ. Bacterial versus archaeal origin of extracellular enzymatic activity in the Northeast Atlantic deep waters. Micro Ecol. 2013;65:277–88.CAS 
    Article 

    Google Scholar 
    50.Thomson B, Wenley J, Currie K, Hepburn C, Herndl GJ, Baltar F. Resolving the paradox: continuous cell-free alkaline phosphatase activity despite high phosphate concentrations. Mar Chem. 2019;214:103671.CAS 
    Article 

    Google Scholar 
    51.Lei L, Cherukuri KP, Alcolombri U, Meltzer D, Tawfik DS. The dimethylsulfoniopropionate (DMSP) lyase and lyase-like cupin family consists of bona fide DMSP lyases as well as other enzymes with unknown function. Biochemistry. 2018;57:3364–77.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar 
    52.Ferla MP, Brewster JL, Hall KR, Evans GB, Patrick WM. Primordial‐like enzymes from bacteria with reduced genomes. Primordial-like enzymes from bacteria with reduced genomes. Mol Microbiol. 2017;105:508–24.CAS 
    PubMed 
    Article 
    PubMed Central 

    Google Scholar  More