藜蒴榉祥硕蚧危害初报

对广州市郊局部发生的藜蒴枯萎死亡原因研究结果表明:藜蒴枯萎死亡主要由榉祥硕蚧Kuwania biporaBorchs引起。初期在受害植株树干及树叶上可见少量蚧虫,树冠基部叶片开始黄化,树势渐变弱。后期可见树干及树枝表面有大量被白色棉絮状物包被的雌蚧虫及红色若虫,树干韧皮部变褐,植株枯萎死亡。10月虫口密度最大。植株死亡高峰为12月到次年3月。干旱和雨季可加剧植株死亡进程。

Damage on Castanopsis fissa caused by Kuwania bipora

Kuwania bipora Borchs caused wilt and death of Castanopsis fissa in the suburb of Guangzhou in recent years.In the initial stage,there were a few scale insects on the trunks and leaves of Castanopsis fissa,leaves in lower part of tree crown became yellow and vigour of the tree weak ened.Later on,lots of female adults and red nymphs coated by white floccules appeared on the trunk and bough,the phloem got brown and plant wilted.The population density reached the highest in October and the peak of plant mortality lasted from December to March the next year.Drought or rainy climate would intensify the process of death.