Study on Relationships among Tobacco-growing Soil Nutrient Content, Microbe Number and Tobacco Quality in Yunnan

ZHANG Xiaolong; XUE Hongfen; LUO Huayuan; CHEN Yunjiao; ZHOU Fangfang; LONG Minghai

Abstract：Relationships among tobacco-growing soil nutrient content,microbe number and tobacco quality were studied in Yunnan,so as to explore the effect of soil nutrient content and microbe number on the quality of tobacco,finally provide a theoretical basis for rational fertilization and tobacco quality improve-ment. The results showed that soil nutrient content had a direct effect on tobacco quality. Soil potassium was the main source of tobacco potassium. Nitrogen in soil strongly influenced tobacco leaf nicotine con-tent,total nitrogen content,concentration and irritation. However,tobacco quality was indirectly affected by the microbes through transformation of soil nutrient. The number of actinomycetes in soil significantly or extremely significant positively correlated with total nitrogen content,available potassium content in soil, potassium content and combustibility of tobacco leaf,but significantly or extremely significantly negatively correlated with chloride content,irritation and aftertaste of tobacco leaf. The correlations between bacteria number in soil and organic matter in soil,total sugar of tobacco leaf were significantly positive,but signifi-cantly negative with irritation of tobacco leaf. It could be concluded that actinomycetes improved soil nitro-gen and potassium transformation,usage,plant absorption,and were good at promoting tobacco combus-tion;bacteria promoted decomposing of organic matter in soil,and reduced tobacco irritation.