黛袋蛾对3种不同桉树的取食嗜好比较

Feeding Preferences of Dappula tertia (Lepidoptera:Psychidae) Larvae to Three Eucalyptus Species

采用叶碟法测定黛袋蛾对3种不同桉树的取食嗜好,并通过单头饲养试验,测定黛袋蛾4龄幼虫对3种不同桉树的转化率和利用率。结果表明:黛袋蛾幼虫喜食尾叶桉叶片,其取食量大小顺序为尾叶桉>大叶桉>窿缘桉。黛袋蛾幼虫对桉树叶龄也具有选择性,对尾叶桉成熟叶的取食量是嫩叶的2倍多。试验结果还表明:黛袋蛾4龄幼虫对尾叶桉的利用率和转化率较高,而对大叶桉和窿缘桉的利用率和转化率相对较低。黛袋蛾对不同桉树的嗜食差异,是桉树人工林营造中合理选择树种的重要依据。

The feeding preferences of Dappula tertia larvae to three Eucalyptus species were detected with a leaf disc method. The efficiency of conversion of digested food（ECD） and efficiency of conversion of ingested food（ECI） of 4th instar larvae to three Eucalyptus species were measured by independent experiments. Dappula tertia larvae preferred E. urophylla leaves to those of E. robusta and E. protruding. The larval preferences to leaf age were also observed. The larvae consumed E. urohpylla mature leaves twice as much as those of tender leaves. The results also showed that the 4^th instar larvae utilized and conversed E. urohpyUa leaves more effectively than the leaves of E. robusta and E. protruding. The mechanisms of preferences and their importance for selection of Eucalyptus species in plantations were discussed.