番茄田二代棉铃虫发生规律及药剂防治

第 2代棉铃虫Helicoverpaarmigera是危害番茄最严重的世代 ,95 %左右的卵产在番茄植株顶尖至第 4复叶层的嫩梢、嫩叶、果萼和茎基上 ,6月 2 0日至 7月 5日累计平均每株落卵 32 8粒。在番茄上第 2代棉铃虫的卵量和幼虫量与第 1代蛾量密切相关 ,卵量 (Y1)与第 1代蛾量 (x)关系式为 :Y1=-31 5 9+ 1 7783X ,n =6 ,r=0 85 6 2 ,幼虫量 (Y2 )与第 1代蛾量 (X)关系式为Y2 =31 3+ 0 1 34X ,n =6 ,r=0 86 5 2 。在第 2代棉铃虫产卵初盛期应用Bt菌剂含孢子 1 0 0亿个 mL ,2 0 0倍液喷雾 3次 ,或 1 8%阿维菌素 1 2 1 5g (a .i.) hm2 兑水喷雾 2次 ,防效显著。

Occurrence and chemical control of the second generation of cotton bollworm(He licoverpa armigera) in tomato field

The damage of the second generation cotton bollworm to tomato is much serious in Laixi, Shandong Province. 95% eggs is laid on the tender top, tender calyx and the base of stem. There are 32 8 eggs on average each plant from June 20 to July 5. The relationship among the density of eggs( Y 1 ), the number of the first generation larvae ( Y 2 ), and the number of the first generation moths ( X ) is as follows: Y 1=-315 9 1 7783X,r=0 8562 *,n=6; Y 2=31 3 0 134X,r=0 8652 *,n=6. The high control efficiency could be obtained by using Bt(200 times dilution, 10 billion/mL spore) spraying 3 times or 1^8% avermection(12 15 g (a.i.)/hm 2) spraying 2 times in the early and peak time of laying eggs.