柑桔园释放印巴黄蚜小蜂防治红圆蚧的试验

EXPERIMENTAL RELEASE OF APHYTIS MELINUS TO CONTROL AONIDIELLA AURANTII IN A CITRUS ORCHARD IN GUANGDONG

盾蚧长缨蚜小蜂和岭南蚜小蜂为广东柑桔园红圆蚧的主要寄生蜂。１９８８年我们从美国加州引入印巴黄蚜小蜂，经繁殖后在桔园分３次释放，每树共放蜂４０００头。结果说明该蜂能成功地在广州越冬。在桔园原有的天敌基础上释放印巴黄蚜小蜂后，红圆蚧的总寄生率逐月变化较大，多数月份在２０％左右，最高３０％，最低９．５％。其中被盾蚧长缨蚜小蜂寄生的虫数，每月都高于岭南蚜小蜂和印巴黄蚜小蜂的总和，寄生率高出１．４～１１．７％。

Encarsia citrina (EC) and Aphytis lingnanesis (AL) are two primary paras itoids of Aonidiella aurantii in Guangdong citrus orchards. In 1988, we intr oduced Aphytis melinus (AM) from California. After a series of propagation, this exotic parasitoid was released three times in a ctrus orchard, with a total number of about 4,000 pertree (to cope with the existing population of both EC and AL). We analyzed the rate of overall parasitism as well as the parasitic rat es of each species. It was found that EC was by far the most efficient parasitoi d. It worked better than AL and AM working together (parasitic rate 1.4 to 11.1% higher). The introduced species did not show too much advantage. It could overwi nter in Guangdong climate, however.