Abstract
Early root establishment is vital for tobacco survival under low-temperature stress in southern China. This field study evaluated potassium humate (PH), Hymexazol and Isorothiolane emulsifiable concentrate (HIEC), and chitosan (CS). Compared to the control group (CG), PH and HIEC emerged as the most effective treatments. Agronomic traits (e.g., root length, leaf number) increased by 5.41% to 24.31% and 15.00% to 80.91% relative to the CG, respectively, while dry matter and nutrient accumulation (nitrogen, phosphorus, potassium) significantly enhanced by 10.84% to 64.83% and 28.03% to 100%, respectively. Mechanistically, PH employed a “Soil-Optimization Strategy,” improving soil pH and organic matter while maintaining microbial diversity. Conversely, HIEC utilized a ‘Functional Selection Strategy,’ stimulating growth by selectively enriching protective genera such as Gaiella and Sphingomonas (reaching relative abundances of 11.36% and 3.60%, respectively, compared to the CG), despite reducing overall bacterial diversity. Furthermore, correlation analysis revealed a positive feedback loop where root expansion enhanced Nitrogen/Potassium uptake, boosting relative chlorophyll content (SPAD) and fueling biomass accumulation. These findings highlight that distinct ecological pathways, specifically soil amelioration and functional microbiome selection, effectively drive crop resilience, providing practical cultivation measures for the tobacco industry to overcome adverse climatic conditions.
Data availability
The raw 16 S rRNA sequencing data generated in this study have been deposited in NCBI SRA under accession number PRJNA1381751. All other datasets, including agronomic measurements, root traits, soil physicochemical properties, SPAD values, and nutrient accumulation, are available from the corresponding author upon reasonable request (contact: [[email protected]]) NCBI Reviewer Link: [https://dataview.ncbi.nlm.nih.gov/object/PRJNA1381751?reviewer=qc5p10q4is7jhtfmllhalssqgi].
Abbreviations
- AN:
Alkali-hydrolyzable nitrogen
- AP:
Available phosphorus
- AK:
Available potassium
- CS:
Chitosan
- CG:
Control group
- HIEC:
Hymexazol and isorothiolane emulsifiable concentrate
- K:
Potassium
- K₂O:
Potassium oxide
- N:
Nitrogen
- P:
Phosphorus
- P₂O₅:
Phosphorus pentoxide
- PH:
Potassium humate
- SOM:
Soil organic matter
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EAA and LY contributed to the conception and design of the work; LY, ZT, DX, AC, and SD contributed to the acquisition, analysis, and interpretation of data; LY, RI, and DX contributed to the creation of new software; LY, EAA, RN, DX, and YL drafted the work and substantively revised it. All authors reviewed and approved the final manuscript.
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The collection of tobacco plants and field studies were conducted in accordance with institutional and national guidelines. All samples were taken with landowner consent and for research use only.
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Li, Y., Azman, E.A., Ismail, R. et al. Effect of root promoter on tobacco (Nicotiana tabacum L.) growth and nutrient accumulation at Hunan Province, China.
Sci Rep (2026). https://doi.org/10.1038/s41598-026-40215-0
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DOI: https://doi.org/10.1038/s41598-026-40215-0
Keywords
- Root promoters
- Rhizosphere microbiome
- Root morphogenesis
- Nutrient accumulation
Source: Ecology - nature.com
