Effects of biochar application on tobacco quality and soil bacterial community structure
[Objective]The paper aimed to study the effects of biochar application on the quality of cured tobacco,soil nutrients and soil mi-crobial 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:Con-ventional fertilization+biochar 2250 kg/hm2;SWT4:Conventional fertilization+biochar 3000 kg/hm2)to determine the chemical compo-sition,sensory quality of cured tobacco and the soil nutrients,rhizosphere soil bacterial 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 SWT1 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 aroma quality,aroma amount,concentration,strength,impurities,usage value,and total score,respectively.With the increase of biochar application rate,the bacterial richness(Chao1 index),diversity(Shannon index),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,g__Neorhizobium,g__Pararhizobium,g__Rhizobium and other nitrogen fixing bacteria,as well as f__uncultured_Actinobacterium,f__Burkholderiaceae,f__Pseudomonadaceae,o__Pseudomonadale,g__Pseudomonas,g__Sphingopyxis,g__Dyella,g__Massilia and other growth promoting bacteria.The application of biochar decreased the relative abundance of denitrifying bacteria such as s__unclassified_Anaerolineaceae and g__unclassified_Caulobacteraceae.At the ASV classification level,AN was the dominant factor affecting the changes in soil bacterial community structure.[Conclusion]The appli-cation of biochar improve the sensory quality of cured tobacco leaves,with SWT3 treatment(2250 kg/hm2)performing the best.The applica-tion of biochar reduce rhizosphere soil bacteria α-diversity,and increase the relative abundance of beneficial bacteria such as nitrogen fixing bacteria,growth promoting bacteria,and denitrifying bacteria in the rhizosphere soil,which is beneficial for increasing soil nutrients and pro-moting plant growth.
Flue-cured tobaccoBiocharQuality of flue-cured tobaccoSoil nutrientsSoil bacterial community structure
万方数据
维普
