摘要
本文报告球形芽孢杆菌在重污水轻污水和清水中孢子数的差异及其对淡色库蚊幼虫毒大影响,以探讨球形芽孢杆菌(以下简称B.S)在水环境中再生的可能性。结果孢子在清水中持续最短,至14天仅能检出原孢子数的1/10左右,但生物测定结果对库蚊幼虫具有轻微的毒力,不具有WHO所定义的再生是产生后续杀虫力的作用。另外,重污水中B.S孢子虽然持续最久,但试验第一天对幼虫毒力反而很低,推测污水中悬浮颗粒干扰幼虫摄入孢子。
The present article deals with the results of the studies on the recycling of Bacillus sphaericus in sewage and clean water. We detected the dyna- mics of its spores number and toxicity against the larvae of Culex pipiens pallens. We found that the spores number declined most repidly in the clean water, the persistance only 1 day, next is in slight water, almost 7 days, but persisted up to 14 days in sewage. However, the larvae mortalit- ies 0% in the clean water, 12% in the slight water, and 22% in the heavy sewage water after 14 days the dosage 3. 9×10~4 CFU/ml of B. S. appl- ied. It seems that the particles in the sewage act as the competitor to interfere B. S. fed by the mosquito larvae in the first day. This observations indicted that there is no any applicable significans to kill the mosquito larvae as so called 'recycling' WHO defined.
