矢尖蚧幼蚧爬行行为的观察

OBSERVATIONS ON THE BEHAVIOR OF ARROWHEAD SCALE, UNASPIS YANONENSIS KUWANA [HOM.:DIASPIDIDAE] CRAWLERS

矢尖蚧全天均可孵出,白天孵出虫数占69.77～76.98％。90.59％的蚧虫白天爬上柑桔叶片。在光照条件下,雄幼蚧爬行平均15.7小时,雌蚧17.6小时。黑暗能缩短爬行期,提早定居。幼蚧对多种光源均有正趋性,其中黑光灯的诱虫效果优于日光灯。黑光灯加寄主植物诱虫效果优于单独用黑光灯。成熟南瓜是繁殖该蚧的适宜寄主植物。在中国南瓜和印度南瓜上成活率均在90％以上。试验提示,在室内培育矢尖蚧时,通过控制光照诱集,使之直接爬上南瓜,可以减少幼蚧的失散和死亡。

Although hatching of the arrowhead scale crawlers may occur anytime in a day, 69.7-76.9% of the hatching and 90.6* of the crawling-onto-citrus leaves were observed to take place during day time. Under illuminated laboratory conditions, the average crawling time of the scales (from, hatching to settle down) was 18.7 hr. for the males and 17.6 hr. for the females. This period was shortened under the dark. The crawlers showed positive phototaxis to various light sources. Stronger phototaxis by the crawlers was shown to ultraviolet light plus host plant than that to ultraviolet light alone, and the latter was yet stronger than that to fluorescent light. Survival rate of the scale was over 90% on either the indigenous squash or the Indian varieties. Thus, by manipulating the lighting conditions to attract the crawlers moving directly onto the squash and settling down, the dispersal and mortality of the young crawlers may be greatly reduced in the mass rearing of the scale.