施用生物炭对烟叶品质和土壤 及其细菌群落结构的影响.

[Objective] The paper aimed to study the effects of biochar application on the quality of cured tobacco, soil mutrients and soil microbial community structure. (Method) A randomised block group field experiment was conducted using Yunyan 87 as the experimental mate rial. Four treatments were set up (SWT1: Conventional fertilization; SWT2: Conventional fertilization biochar 1500 kg/hm²; SWT3: Conventional fertilization + biochar 2250 kg/hm²; SWT4: Conventional fertilization biochar 3000 kg/hm²) to determine the chemical composition, sensory quality of cured tobacco and the soil nutrients, rhizosphere soil hacterial diversity of the cured tobacco at maturity. [Result] The application of biochar had no significant influence on the soil nutrients and chemical composition of cured tobacco. Compared with the SWTI treatment, the sensory quality of cured tobacco was significantly improved in all treatments of biochar application, among which SWT3 treat- ment showed the best performance with 13.85%,6.56%,10.87%,8.70%,4.62%,12.31% and 6.25% improvement in amma quality, aroma amount, concentration, strength, impurities, usage value, and total score, respectively. With the increase of biochar application rate, the bacterial richness (Chaol index), diversity (Shannon indes), total ASV number and unique ASV number in the rhizosphere soil of flue- cured tobacco showed a decreasing trend. Compared with SWT1 treatment, the difference in microbial community structure composition incre aed with the increase of biochar application rate. The dominant phyla of each treatment were Proteobacteria, Acidobacteria and Actinobacte ria, At the phylum classification level, there was no significant difference in the community structure composition among different treatments. The application of biochar increased the relative abundance of f Rhizobiaceae, g Allorhizobium, Neorhizobium, g Pararhizobium, g Rhizobium and other nitrogen fixing bacteria, as well as funcultured_Actinobacterium, f Burkholderiaceae, Pseudomonadaceae, o Pseudomonadale, g Pseudomonas, g Sphingopyxis, & Dyella, g Massilin and other growth promoting bacteria. The application of biochar decreased the relative abundance of denitrifying bacteria such as sunclassified_Anaerolinencrar and g unclassified Caulobacteracene. At the ASV classification level, AN was the dominant factor affecting the changes in soil bacterial community structure. [Conclusion] The application of biochar improve the sensory quality of cured tobacco leaves, with SWT3 treatment (2250 kg/hm²) performing the best. The application of biochar reduce thizosphere soil bacteria a-diversity, and increase the relative abundance of beneficial hacteria such as nitrogen fixing bacteria, growth promoting bacteria, and denitrifying bacteria in the thizosphere soil, which is beneficial for increasing soil nutrients and promoting plant growth. [ABSTRACT FROM AUTHOR]