棉铃虫对辛硫磷抗性的选育、交互抗性及增效剂增效作用研究

Laboratory Selection for Phoxim Resistance, Cross Resistanceand the Synergism of Several Synergists in Helicoverpa amigera Hübner

1 991年采自河南偃师棉田的棉铃虫种群(简称 YS种群 )与敏感品系相比有 2 .7倍的抗性。该种群在室内经功夫菊酯 +辛硫磷 (1∶ 2 5 )筛选了 2 7代后 ,对辛硫磷的抗性达到 9.4倍 ,再单用辛硫磷对该种群筛选 2 1代 ,获得 6 3 .0倍的抗性。交互抗性测定结果表明 ,棉铃虫对辛硫磷产生高水平抗性后对灭多威具有比较明显的交互抗性 ,对久效磷具有一定程度交互抗性 ,对甲基对硫磷和丙溴磷只有较低水平的交互抗性。 3种增效剂 TPP、DEF和 PBO对辛硫磷的增效比分别为1 .4、2 4 .8和 1 .0 ,DEF的增效作用明显 ,使辛硫磷的抗性由 6 3倍降至 2 .5倍 ,初步证明酯酶是引起棉铃虫对辛硫磷产生抗性的重要原因。

A field collected strain (HNYS) of Helicoverpa armigera in cotton in 1991 had 2.7 fold resistance to phoxim compared to a laboratory susceptible strain (SUS). After HNYS strain was selected with a mixture of phoxim+cyhalothrin (25∶1 A.I.) for 27 generations, the resistance to phoxim increased from 2.7 fold to 9.4 fold. Then this strain was further selected by phoxim alone for 21 generations and the phoxim resistance increased from 9.4 fold to 63.0 fold. The phoxim resistant strain had high level cross resistance to methomyl (45.5 fold), middle level to monocrotophos (17.9 fold), and low level to methyl parathion (8.7 fold) and profenofos (4.8 fold). Synergism ratios of TPP, DEF and PBO to phoxim in the selected HNYS strain were 1.4, 24.8 and 1.0 fold respectively. Significant synergism of DEF to phoxim (resistance decreased from 63.0 to 2.5 fold) indicated esterase appeared to be an important resistance factor in this laboratory selected resistant strain. These results are indicative in designing phoxim resistance management strategies such as alternating, rotating and mixing insecticides.