粗胫翠尺蛾对不同荔枝品种的选择性研究

Study on the selectivity of Thalassodes immissaria(Lepidoptera: Geometridae) to litchi varieties

通过田间调查、电生理和行为学测定,研究了粗胫翠尺蛾(Thalassodes immissaria Walker)对5个荔枝品种(‘糯米糍’、‘妃子笑’、‘桂味’、‘黑叶’、‘淮枝’)的选择性。连续3 a田间调查显示,‘糯米糍’和‘妃子笑’受害较重,100梢虫数量平均为66.87头和58.70头,而‘淮枝’受害较轻,100梢虫数量平均为29.80头。粗胫翠尺蛾对‘桂味’、‘糯米糍’和‘妃子笑’3个品种叶片气味的相对触角电位值高于‘黑叶’,而对‘淮枝’的反应值最低。在Y型嗅觉仪测试中,粗胫翠尺蛾成虫更趋向于‘糯米糍’和‘妃子笑’,而对‘淮枝’的趋向性最差,‘糯米糍’和‘妃子笑’相比差异不显著。这些试验结果共同证明了粗胫翠尺蛾对5个荔枝品种具有选择性,而荔枝叶片气味在粗胫翠尺蛾寄主选择时具有重要的行为导向作用。

The selectivity of Thalassodes immissaria Walker to five litchi varieties, ＇ Nuomici＇, ＇ Feizixi- ao＇, ＇ Guiwei＇, ＇ Heiye＇ and ＇ Huaizhi＇, was investigated by field survey, EAG and behavioral response tests. The results showed that ＇Nuomici＇ and ＇Feizixiao＇ were damaged seriously, the population densi- ties were 66.87 and 59.40 every one hundred shoots, respectively, while ＇Huaizhi＇ was damaged lightly, the population densitie was 29.80. T. immissaria had significantly higher EAG response to ＇Guiwei＇, ＇ Nuomici＇ and ＇ Feizixiao＇ than to ＇ Heiye＇, and ＇ Huaizhi＇ had the lowest response. In the Y-tube tests, ＇Nuomici＇ and ＇Feizixiao＇ had the most attractive effect on T. immissaria, and ＇Huaizhi＇ was the weak- est, but there was no significant difference between ＇Nuomici＇ and ＇Feizixiao＇. All the result proved that T. Immissaria had selectivity to the varieties of litchi and the volatiles of litchi leaves had important behav- ioral orientation function, but the reaction between T. Immissaria and litchi volatiles required further study.