玉米螟厉寄蝇Lydella grisescens Robineau-Desvoidy是玉米螟的主要天敌之一。几年来我们作了一些观察试验,现把结果报导如下。 (一) 寄生率调查根据几年来的观察,第一代玉米螟幼虫被寄生率一般为30—40％,个别地块达80％,平均寄生率第一代为42％,第二代28.7％(详见表1)。在玉米螟严重发生的年份和集中发生的地块,被寄生率则更高。 Lydella grisescens Robineau-Desvoidy is one of the major natural enemies of corn borer. In recent years we made some observations and experiments, the results reported below. (A) parasitism survey According to the observations over the years, the first generation of corn borer larvae parasitic was generally 30-40%, 80% of individual plots, the average of the first generation of parasites was 42%, the second generation of 28.7% (See Table 1 for details). In the serious occurrence of corn borer and concentrated occurred in the plot, the parasitism rate is even higher.