Effects Of Base Application Of Bacillus Subtilis On Growth,Development And Yield&Quality Of Flue-Cured Tobacco

In this paper,we changed the base application amount ofbacillus subtilis（0 kg/hm²、15 kg/hm²、30 kg/hm²、45 kg/hm²）and discussed it how to impat on the agronomic trait,physiological index and photosynthetic physiological characteristics of the tobacco,main chemical component,appearance and tasting assess value in quality of flue-cured tobacco,and main aromatic substance of smoke.Finally,it provides theoretical basis and reference for the application ofbacillus subtilisin flue-cured tobacco production.Currently,the following results has been made:1.Impact on agronomic characters7 days after topping,agronomic traits of tobacco increased with the increase of bacillus subtilii base application amount,and the treatment effect of 45 kg/hm2 base application amount was the best,among which plant height,stem circumference,node distance and maximum leaf area were improved by 6.64%,4.51%,23.9% and 9.72%,respectively.2.Impact on the physiological index7 days after topping,with the increase ofbacillus subtilisbase application amount,the maximum leaf SPAD value,root volume,and root activity all increased,but there was no significant difference between treatments and different application amount.Similarly,maximum leaf net photosynthetic rate,transpiration rate and stomatal conductance increased,while intercellular CO₂concentration and leaf surface water pressure deficit decreased.Moreover,the treatment with 45 kg/hm²of bacillus subtilis had the best effect on the photosynthetic physiological.3.The impact on the main economic character index of tobacco leafThe proportion of superior tobacco,proportion of Upper-Intermediate tobacco and output value of roasted tobacco increased with the increase ofbacillus subtilisbase application amount.The proportion of superior tobacco and output value of treated tobacco were significantly higher than the control with 45 kg/hm²base application amount.The main economic characters of tobacco leaf index of economic effect index（ECI）that seems as the base application amount treat of 45 kg/hm²> 30 kg/hm²>15 kg/hm²> 0 kg/hm²（ck）,and the ECI of base application amount treat of 45 kg/hm²treatment > 30 kg/hm²is significantly higher than 0 kg/hm²treatment（CK）.4.The impact on the quality of flue-cured tobaccoThrough the test and analysis of the appearance and smoking quality of B₂F and C₃F of toasted tobacco leaves,it was found that the total score of the appearance and smoking quality weight increased with the base application amount increasing ofbacillus subtilis,but there was no significant difference between the two treatments.5.The impact on aromatic substance of smoke in different treatmentBacillus subtilishad a certain effect on the content of aromatic substances in tobacco leaves after roasting.In B₂F tobacco leaves,1)the total amount of petroleum ether extract treated with base application ofBacillus subtiliswas 1.00% 1.32% higher than that of the control group;2)The total carotenoid aroma of the treatment group was 1.00%¹.32% higher than that of the control check;3)the total amount of degradation products of the treatment group was 2.9 μg/g 10.3 μg/g higher than that of the control check;4)the total solanone content of the treatment group was 4.0 μg/g 8.2 μg/g higher than that of the control check;5)the total amount of non-enzymatic Browning reaction products of the treatment group was 3.9 μg/g 9.5 μg/g higher than that of the control check;6)the total amount of aromatic amino acid cleavage products of the treatment group was 2.0 μg/g 8.2 μg/g higher than that of the control check;7)the total amount of new phytadiene of the treatment group was 36.2 μg/g 164 μg/g higher than that of the control check;8)the total amount of neutral odorants of the treatment group was 54.1 μg/g, 107.4 μg/g higher than that of the control check.In C₃F tobacco leaves,1)the total amount of petroleum ether extract treated with base application ofBacillus subtiliswas 1.26% 1.46% higher than that of the control group;2)The total carotenoid aroma of the treatment group was 1.8%².5% higher than that of the control check;3)the total amount of degradation products of the treatment group was 6.3 μg/g 12.2 μg/g higher than that of the control check;4)the total solanone content of the treatment group was 4.4 μg/g 9.9 μg/g higher than that of the control check;5)the total amount of non-enzymatic Browning reaction products of the treatment group was 4.0 μg/g 9.5 μg/g higher than that of the control check;6)the total amount of aromatic amino acid cleavage products of the treatment group was 3.8 μg/g 8.6 μg/g higher than that of the control check;7)the total amount of new phytadiene of the treatment group was 62.8.2 μg/g 189 μg/g higher than that of the control check;8)the total amount of neutral odorants of the treatment group was 47.9 μg/g, 88.0 μg/g higher than that of the control check.The higher of the base application rate,the higher of the aroma content of tobacco leaves.6.The impact on the tobacco availability index of major chemical componentsThrough the analysis of the B₂F and C₃F tobacco major chemical components and calculation of availability index,they seem as: Base application amount treat of 45 kg/hm²treatment（T3）>30 kg/hm²treatment（T2）>15 kg/hm²treatment（T1）>0 kg/hm²treatment（T4,CK）,and significantly higher than the control.SoBacillus subtiliscan significantly improve the chemical composition availability index of tobacco leaves,coordinate the internal chemical composition of tobacco leaves,and improve the quality of tobacco leaves.The results concluded from above showed that base application ofbacillus subtilisin tobacco planting soil had certain effects on promoting the growth and development of tobacco plants,increasing the yield of tobacco leaves and improving the quality of tobacco leaves.it is suggested to use the base application amount treat of 30 kg/hm² 45 kg/hm²for production,which is more economical and effective.