摘要
在二代棉铃虫Heliothis armigera卵高峰期,一般年份用200倍,大发生年份用100倍苏云金杆菌(B.t.)乳剂喷雾防治效果达75%以上,可将虫口密度压低到经济损失允许水平以下。防治后调查生防田主要捕食性昆虫天敌比化防田高3倍左右,对伏蚜有较好的控制作用。伏蚜高峰期主要捕食性天敌与伏蚜之比,维持在1:200以上水平,可将防治伏蚜时间推迟10—15天,减少防治1—2次。
0.5% in normal Years or 1% in outbreak years of B.t.emulsion(a
preparation of Bacillus thuringiensis),spraying at the egg peak of second
generation of cotton bollworm Heliothis armigera,got more than 75%
mortality of larvae and kept its population density below the economic
injury level.The number of major predators in B.t.treated field is three
times more than in insecticide treated field,and maintained the ratio
of predators/summer cotton aphid over 1:200 in peak aphid period.
The timing and times of control in B.t.treatment were 10—15 days later
and 1—2 times less,respectively,than those in insecticide treatment.
出处
《植物保护学报》
CAS
CSCD
北大核心
1991年第3期207-210,共4页
Journal of Plant Protection
关键词
苏云金杆菌剂
棉铃虫
昆虫
天敌
Bacillus thuringiensis
cotton bollworm
natural enemies
summer cotton aphid
