【摘要】 苏云金杆菌3个变种的芽孢与晶体按重量百分比混合,以亚洲玉米螟1龄和2龄幼虫测定毒力。对1龄幼虫主要致病因素是晶体。对2龄幼虫,“HD—1”以晶体为主;SB—14菌株当芽孢与晶体1:1时,杀虫效果最好;E743—4菌株以芽孢为主。更多还原

【Abstract】 Three commonly used strains of B. thuringiensis, HD-1, E763-4 and SB-14 with various weight proportions of crystals (C) to spores (S) were assayed for their toxicity against the 1st and 2nd instars of O.furnacalis. Crystals of the three strains were the main toxic agent to the 1st instar larvae. Whereras the highest mortality of the 2nd instars was obtained from the crystals of HD-1, spores of E743-4, and a 50% C:50% S mixture of SB-14, respectively.更多还原