摘要
苏云金杆菌(Bacillusthuringiensis简称Bt)的晶体蛋白是主要的杀虫成分,抗紫外照射能力差,造成野外防治过程中易失活、防效不稳定、残效期短。为改良Bt剂型,探讨了以明胶-阿拉伯胶为囊壁材料的复凝聚相分离法制备Bt微胶囊剂的加工工艺,并用平板活菌计数法对得到的Bt微胶囊剂进行了抗紫外能力分析及用毒力测定法比较微胶囊前后的杀虫活性。结果表明,经过紫外2h的照射,原Bt菌液平板活菌计数成活率只有11.4%,微胶囊化后的Bt菌液成活率高达78%;相应地,原Bt菌液已基本丧失杀虫活性,而微胶囊化后的Bt菌液对小菜蛾致死率仍达66.7%,比原菌液抗紫外能力大大增强。
Bacillus thuringiensis crystal protein was a key active ingredient to kill insects, which was sensitive to ultra violet in the field. The naked Bacillus thuringiensis was the less activity, unstable and reduced the time of residual toxicity. In order to improve the effect, we studied how to pack the Bacillus thuringiensis into the microcapsule of double phase separation-coacervation used by gelatin glue-acacia glue. The experiment was designed by the orthogonal test with four group parameters of wall density, Bacillus concentration, temperature and shaking rate. The goal character, such as, appearance and character, suspend, rate of inwrap, average diameter, storage stability and virulence were checked and compared. The result indicated that Bacillus concentration 1%, the concentration of gelatin glue-acacia glue 3%. the system temperature 50℃, and shaking rate 200 r·min^-1. The effect on the UV resistant by counted living bacterium with plate cultivation and the toxicity of the Bacillus thuringiensis microeapsule were investigated by the naked Bacillus thuringiensis as a contrnl, the results show that the survival so low, the rate of microcapsule Bacillus thuringiensis was 78% and the control only 11.4%. after two hours shinning of UV, the 66.7% of small cabbage moth can be killed by the mieroeapsule Bacillus thuringiensis and ahnost all the moth was aliving at the control group.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2005年第5期966-969,共4页
Journal of Agro-Environment Science
基金
浙江省自然科学基金资助(399437)
关键词
苏云金杆菌
复凝聚相
微胶囊剂
Bacillus thuringiensis
double phase separation-coacervation
microeapsule
