title: Microbial Biofertilizer Decreases Nicotine Content by Improving Soil Nitrogen Supply.
abstract: Biofertilizers have been widely used in many countries for their benefit to soil biological and physicochemical properties. A new microbial biofertilizer containing Phanerochaete chrysosporium and Bacillus thuringiensis was prepared to decrease nicotine content in tobacco leaves by regulating soil nitrogen supply. Soil NO3--N, NH4+-N, nitrogen supply-related enzyme activities, and nitrogen accumulation in plant leaves throughout the growing period were investigated to explore the mechanism of nicotine reduction. The experimental results indicated that biofertilizer can reduce the nicotine content in tobacco leaves, with a maximum decrement of 16-18 % in mature upper leaves. In the meantime, the total nitrogen in mature lower and middle leaves increased with the application of biofertilizer, while an opposite result was observed in upper leaves. Protein concentration in leaves had similar fluctuation to that of total nitrogen in response to biofertilizer. NO3--N content and nitrate reductase activity in biofertilizer-amended soil increased by 92.3 and 42.2 %, respectively, compared to those in the control, whereas the NH4+-N and urease activity decreased by 37.8 and 29.3 %, respectively. Nitrogen uptake was improved in the early growing stage, but this phenomenon was not observed during the late growth period. Nicotine decrease is attributing to the adjustment of biofertilizer in soil nitrogen supply and its uptake in tobacco, which result in changes of nitrogen content as well as its distribution in tobacco leaves. The application of biofertilizer containing P. chrysosporium and B. thuringiensis can reduce the nicotine content and improve tobacco quality, which may provide some useful information for tobacco cultivation.
authors.affiliation: College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, People's Republic of China.
authors.forename: Cui
authors.initials: C
authors.lastname: Shang
authors.affiliation: College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, People's Republic of China. A.Chen@hunau.edu.cn.
authors.forename: Anwei
authors.initials: A
authors.lastname: Chen
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha, People's Republic of China. gqchen@hnu.edu.cn.
authors.forename: Guiqiu
authors.initials: G
authors.lastname: Chen
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha, People's Republic of China.
authors.forename: Huanke
authors.initials: H
authors.lastname: Li
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha, People's Republic of China.
authors.forename: Song
authors.initials: S
authors.lastname: Guan
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha, People's Republic of China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: He
mesh_terms: D001413:Bacillus thuringiensis / Q000378:metabolism; D005308:Fertilizers / Q000382:microbiology*; D009538:Nicotine / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism; D020075:Phanerochaete / Q000378:metabolism; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D014026:Nicotiana / Q000254:growth & development / Q000378:metabolism* / Q000382:microbiology
chemical_list: D005308:Fertilizers; D012987:Soil; D009538:Nicotine; D009584:Nitrogen
keywords: Bacillus thuringiensis; Biofertilizer; Nicotine; Nitrogen; Phanerochaete chrysosporium; Tobacco