斜斑鼓额食蚜蝇成虫发生动态、产卵习性及其控制温室蚜虫的作用

THE OVIPOSITION BEHAVIOR OF SCAEVA PYRASTRI [HYM.:SURPHIDAE] AND ITS CONTROL EFFECT ON APHIDS IN GREENHOUSES

在北京地区,斜斑鼓额食蚜蝇以交配过的雌成虫在深石缝中越冬。越冬成虫在25±1℃,70～80％RH,16小时光照,供给有蚜苗的条件下当天即可产卵。以花粉健美酥为补充营养时,2月底采集的成虫平均产卵量为235.0±59.3粒/雌,卵的孵化率为64.7％。在花卉温室中,成虫选择蚜虫较多的植株或部位产卵。在非洲菊上尤喜在花上产卵。在14米~2的温室中,分两次释放13头越冬成虫,能有效防治非洲菊上蚜虫,25天中使花上蚜虫下降88.4％,叶上蚜虫下降92.6％。没有食蚜蝇的番茄苗上,12天内蚜虫上升133.3％,需施药防治。

In Beijing area, naturally occurring scaeva pyrastri overwinters as mated female adult in deep stone crevices. When moved into a rearing room of 25±1℃, 70-80% RH, 16 hr photoperiod and provided with aphid infested bean seedlings, the overwintering females began oviposition within 24 hr. When they were provided with a 'Pollen Health Food' as supplementary diet, each overwintered female adult laid an average of 235.0±59.5 eggs with 64.7% hatching rate. In the greenhouses of ornamental flowers, the females showed a preference 'of plants or plant parts infested by large number, of aphids to lay their eggs. On Flameray gerbera, for example, the eggs were mostly found on the flowers. In the experiment conducted in a greenhouse of 14m2, two releases of a total of 13 overwintered femalfe adults resulted in an effective control of the aphids on F. qerbera. The number of aphids on the flowers and leaves reduced by 88,4% and 92.6%, respectively in 25 days after the releases. In comparison, the number of aphid on tomato seedlings in the control greenhouse without releasing the predator increased 133.3% in 12 days. In this case, chemical control became necessary.