Salama H S, Moawed S M
Laboratory of Pests and Plant Protection, National Research Centre, Dokki, Cairo, Egypt.
Acta Biol Hung. 1988;39(1):99-107.
A polyhedrosis virus disease was isolated from the larvae of Agrotis ipsilon. Isolation of causative agent from the infected larvae again showed to be positive. Microscopic examination of the infected larvae (by means of a light microscope) gave an evidence of the development of the polyhedral inclusion bodies (PIB) in all typical tissues where the virus is known to develop. Examination by an electron microscope showed various irregular shaped polyhedra; their diameter being about 1.5 to 3.5 mu. Most of these polyhedra were hexagonal and they measured about 2.2 mu. Experimental studies were conducted to investigate its pathogenicity alone and when combined with chemical insecticides. The joint action of the nuclear polyhedrosis virus of A. ipsilon (AINPV) combined with four chemical insecticides namely Fenvalerate, Decamethrin, Cypermethrin and Methomyl was assessed against the second instar larvae of A. ipsilon. Results showed that Decamethrin was the most toxic compound followed by Cypermethrin and Fenvalerate while Methomyl was the least toxic, the median lethal concentrations (LC50) were 0.25, 0.77, 14 and 450 ppm, respectively. The LC50 value of AINPV was 12 x 10(6) PIB/ml. Mixtures containing sublethal concentrations (LC25 and less) of both AINPV and any of the tested insecticides showed synergistic effects. On the other hand, an additive effect was observed with combinations containing doses of chemical insecticides over the range between LC25 and LC50 values.
从小地老虎幼虫中分离出一种多角体病毒病。再次从受感染幼虫中分离出病原体，结果呈阳性。对受感染幼虫进行显微镜检查（借助光学显微镜）发现，在已知病毒会发育的所有典型组织中，多面体包涵体（PIB）都有发育迹象。电子显微镜检查显示有各种形状不规则的多面体；其直径约为1.5至3.5微米。这些多面体大多为六边形，尺寸约为2.2微米。开展了实验研究，以单独研究其致病性以及与化学杀虫剂联合使用时的致病性。评估了小地老虎核多角体病毒（AINPV）与四种化学杀虫剂即氰戊菊酯、溴氰菊酯、氯氰菊酯和灭多威联合作用于小地老虎二龄幼虫的情况。结果表明，溴氰菊酯是毒性最强的化合物，其次是氯氰菊酯和氰戊菊酯，而灭多威毒性最小，其半数致死浓度（LC50）分别为0.25、0.77、14和450 ppm。AINPV的LC50值为12×10⁶ PIB/ml。含有亚致死浓度（LC25及以下）的AINPV与任何一种受试杀虫剂的混合物均显示出协同效应。另一方面，当化学杀虫剂剂量在LC25和LC50值之间时，其组合表现出相加效应。
