粘虫核型多角体病毒感染特性的研究

对东北农业大学昆虫学教研室分离出来的粘虫核型多角体病毒Ｖ－Ｍｓ－４毒株进行初步研究，结果表明，病毒多角体呈近圆形、四角形、六角形和不规则形，大小在１．１６～２．８６μｍ之间，病毒粒子为３８９～４６７μｍ×４０～６８μｍ，为多粒包埋，病毒在粘虫消化液作用下，１０ｍｉｎ失去折光性，３０ｍｉｎ内完全被溶解，释放出病毒粒子；消化液能使释放出的病毒粒子在１５ｍｉｎ内失活；寄主的脂肪、气管基质及表皮组织为感染病毒的敏感组织，感染后脂肪和血淋巴蛋白的含量比健康幼虫明显降低，未见病毒侵染中肠的现象。

STUDY ON INFECTIVITY OF MYTHIMNA SEPARATA NUCLEAR POLYHEDROSIS VIRUS V-MS-4 STRAIN

Infectivity of Mythimna separata nuclear polyhedrosis virus(MsNPV) which was isolated from diseased M separata larvae by Northeast Agricultural University in 1983 was studied The result showed that the polyhedra were nearly round, tetrahedral, hexangular and irregular and ranged from 1 16 to 2 86 μm in size Virions released from polyhedra were measured 389～467nm×40～68nm by electron microscope The effect of M separata digestive fluid on infectivity of the virus was tested, the polyhedra lost their refringence by 10 minutes of exposure to digestive fluid, then were dissoluted after exposure to the fluid for 30 min The virions were rapidly inactivated and all of virions became non-infectious after 15 mintes of exposure to the fluid Fat bodies, tracheal stroma and epidermal tissue of host were considered susceptible to the virus The fat content and the concentration of hemolymph protein in diseased larvae were found to be clearly lower than that in the healthy ones during development of larvae But polyhedra were not found in midgut by using light microscope