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根据烟草的类型和起源 ,干烟叶的微生物含量在 10 3～ 10 7CFU(群落形成单位 ) /g之间变化。烟叶上发现 3种微生物 :细菌、酵母和真菌。PhilipMorris欧洲实验室的工作表明 ,将收获后的烟叶进行热处理和干燥 ,几乎只能选出有抗性的形成孢子的杆菌属革兰氏阳性菌。干烟叶上的优势种是短小芽孢杆菌、枯草杆菌、巨芽孢杆菌和地衣型芽孢杆菌。其他杆菌 ,如短杆菌、环状芽孢杆菌、多粘芽孢杆菌、强固芽孢杆菌、凝固芽孢杆菌和苏云金芽孢杆菌 ,也能以较低的频率检测到。这种细菌种群绝大多数是由休眠孢子组成的。非病原性附生细菌的利用 ,表明有机会在寄主植物叶片上目标性地使用生物杀真菌剂和生物杀虫剂。苏云金芽孢杆菌是一种在产孢期产生杀虫结晶蛋白 (ICP)的细菌 ,用于防治食植性害虫。尽管苏云金芽孢杆菌主要是存在于土壤中 ,但近来已从各种叶表面上分离出这种细菌的不同菌株 ,表明可以认为该菌是许多植物叶面微生物的一部分。我们已从复烤烟叶上分离出大量对烟草甲虫 [Lasiodermaserricorne(F .) ;鞘翅目 :窃蠹科 ]这种分布最广和危害最大的仓储烟草害虫的幼虫有杀虫活力的苏云金芽孢杆菌
Depending on the type and origin of the tobacco, the microbial content of the dried tobacco varies between 10 3 and 10 7 CFU (unit of community formation) / g. Three kinds of microbes are found on tobacco leaves: bacteria, yeast and fungi. The work of the Philip Morris European Laboratory shows that almost all of the resistant, spore-forming, gram-positive Gram-positive bacteria can be selected by heat treating and drying the harvested tobacco leaves. The dominant species on dry tobacco are Bacillus pumilus, Bacillus subtilis, Bacillus giantii and Bacillus licheniformis. Other bacilli such as Brevibacterium, Bacillus circulans, Bacillus polymyxa, Bacillus firmus, Bacillus coagulans and Bacillus thuringiensis can also be detected at lower frequencies. The vast majority of this bacterial population is composed of resting spores. Utilization of non-pathogenic epiphytic bacteria suggests the opportunity to target the use of biocides and biocides on host plant leaves. Bacillus thuringiensis is a bacterium that produces insecticidal crystal protein (ICP) during the sporulation period for the control of food-borne pests. Although Bacillus thuringiensis is mainly found in soil, different strains of this bacterium have recently been isolated from various leaf surfaces, suggesting that the bacterium is considered to be part of many plant leaf-surface microorganisms. We have isolated a large number of pairs of tobacco beetles from re-flue cured tobacco leaves [Lasiodermaserricorne (F.); Coleoptera: Lemuridae] The most widely distributed and damaging larvae of tobacco stored insects are insecticidal viable B. thuringiensis