论文部分内容阅读
1981～1982年试验结果表明,HD-1菌剂对稻纵卷叶螟的防治效果为70～82%,并对后代发生数量有一定影响。一般以卵盛孵末期到2龄幼虫发生初期,每亩每次用 HD-1菌剂150克防治两次为宜。室内毒力测定:HD-1菌粉(芽孢与晶体比例为1:1.05)和晶体对稻纵卷叶螟的毒力高,芽孢毒力低。HD-1菌粉处理2龄和3龄幼虫的 LC_(50),活孢子数分别为3.16×10~6个/毫升和3.16×10~7个/毫升。HD-1菌粉(含活孢子数7×10~7个/毫升)对2龄幼虫的 LT_(50),在平均24.6℃下,为15.84小时。HD-1处理后的卵能正常孵化,但能引起初孵幼虫的死亡;5龄老熟幼虫,部分能带毒进入蛹期,引起蛹的死亡。HD-1不杀伤天敌,HD-1防治区的天敌总数、种类比化防区多,天敌增长率也高于化防区。稻田施用 HD-1,能有效地降低土壤、稻谷中化学农药残留量。
The experimental results from 1981 to 1982 showed that the control effect of HD-1 on rice leaf roller is 70-82%, and it has an impact on the number of offspring. In general, egg larvae to the end of the second instar larvae early stage, with 150 grams per acre with HD-1 bacteria prevention and control two times is appropriate. Indoor toxicity determination: HD-1 bacterial powder (spore-to-crystal ratio of 1: 1.05) and crystal toxicity to the rice leaf roller, spore toxicity low. The LC 50 of 2nd and 3rd instar larvae treated with HD-1 was 3.16 × 10 ~ 6 / ml and 3.16 × 10 ~ 7 / ml, respectively. The LT 50 of 2nd-instar larvae of HD-1 (containing 7 × 10-7 viable spores / ml) was 15.84 hours at 24.6 ℃ on average. HD-1 eggs can hatch properly, but can cause the death of newly hatched larvae; 5th-instar larvae, part of the poisoning can enter the pupal stage, causing pupa death. The natural enemies of HD-1 do not kill, and the total number of natural enemies in HD-1 control area is more than that of type II. The growth rate of natural enemies is also higher than that of chemical defense zones. The application of HD-1 in paddy field can effectively reduce the chemical pesticide residues in soil and rice.