Study On Resources Of Bacillus Thuringiensis From Tobacco Warehouse And Characterization Of Novel Strain LY-99

Compared with the soil environment, the resources of Bacillus thuringiensis isolates from tobacco warehouse are very abundant, and the rate of the samples containing Bacillus thuringiensis isolates is very high. Furthermore, there are many specific Bacillus thuringiensis strains in tobacco warehouse. To date, there are little researches about the resources of Bacillus thuringiensis isolates from tobacco warehouse. This paper investigated the distribution of Bacillus thuringiensis isolates in tobacco warehouse based on eight cigarette factories in six different provinces in China, and conducted the research on the genetic diversity of new B. thuringiensis isolate LY-99. This paper was composed of two parts.1. Isolation of the Bacillus thuringiensis from tobacco warehouseBacillus thuringiensis isolates were screened with 578 samples from different tobacco warehouses of eight cigarette factories (Xiangfan Cigarette Factory, Wuhan Cigarette Factory, Longyan Cigarette Factory, Xiamen Cigarette Factory, Yanji Cigarette Factory, Hangzhou Cigarette Factory, Kunming Cigarette Factory and Guangzhou Cigarette Factory). The result showed that the resources of Bacillus thuringiensis isolates from tobacco warehouse were very abundant. 972 Bacillus thuringiensis strains were isolated from 238 out of 578 samples. The total rate of the samples containing Bacillus thuringiensis isolates was 41.18%. On the base of individual cigarette factory, the rate of the samples containing Bacillus thuringiensis isolates of Yanji Cigarette Factory was highest, and followed by Longyan Cigarette Factory (96.15%), Kunming Cigarette Factory (79.37%), Xiangfan Cigarette Factory (78.95%), Xiamen Cigarette Factory (61.11%), Hangzhou Cigarette Factory (29%), Guangzhou Cigarette Factory (22.81%) and Wuhan Cigarette Factory (15.27%). Different types of samples had different rate containing Bacillus thuringiensis isolates, the dust was the highest, and followed by tobacco oddment, tobacco leaf and pest cadaver.2. The molecular characterization of new Bacillus thuringiensis isolate LY-99The primary bioassay showed that LY-99 was highly toxic to Plutella xylostella (Lepidoptera), Spodoptera exigua (Lepidoptera), Ephestia elutella (Lepidoptera), and...