沼液对韭菜迟眼蕈蚊的防治效果

通过室内选择性测定和田间试验,评价了沼液对韭菜迟眼蕈蚊的防治效果。结果表明,沼液对韭菜迟眼蕈蚊表现出一定的驱避活性,对幼虫的驱避率、拒食率分别达55.30%、53.81%,雌雄成虫选择反应率分别为33.2%、30.5%,对雌虫产卵驱避率为36.82%。田间试验结果表明,以沼液∶水(1∶1)处理幼虫、成虫,随着时间的延长防效逐渐提高,处理后45d防效达到最大,分别为43.16%、56.50%。

Control effect of biogas slurry against Bradysia odoriphaga

The activity of 1.6% daphneantoxin EW on Pieris rapae, Plutella xylostella, Acyrthosiphon pisum, Tetranychus truncatus was determined by slide slip method, topical application and leaf-sandwich. Laboratory bioassay results showed that the order of contact toxicity of 1.6% daphneantoxin EW against 4 insects was P. rapae>P. xylostella>A. pisum>T. truncatus. Systemic toxicity analysis indicated that the median lethal concentration (LC50) values for T. truncatus and A. pisum were 149.22 mg/L and 101.76 mg/L, respectively, significantly lower than that of contact toxicity (219.10 mg/L and 165.25 mg/L). Stomach toxicity test by leaf-sandwich indicated that the median lethal concentrations (LC50) for P.rapae and P. xylostella were 342.82 mg/L and 407.34 mg/L, respectively, while the contact toxicity test showed the LC50 values for P. rapae and P. xylostella were 58.61 mg/L and 75.30 mg/L, respectively. The above results demonstrated that 1.6% daphneantoxin EW had good contact toxicity and some stomach toxicity on P. rapae and P. xylostella.