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银杏超小卷叶蛾(Pammene sp.)以幼虫蛀害银杏枝条,使枝条枯死,降低白果产量。在江苏株被害率最高为100％,浙江等地白果减产80～90％。该虫一年一代,以蛹在树干中下部枯皮中越冬,3月下旬至4月中旬羽化,成虫需补充营养,产卵于小枝上,每雌产卵90余粒,寿命约13天。5月上旬孵化为幼虫,初龄幼虫行动活泼,自短枝端部蛀入枝内,或从当年生长枝中部或基部蛀入,每头幼虫可为害短枝2个,幼虫在枝条内约取食25天即外出迁至枯叶中卷叶栖息,有时取食少量叶肉,约经半月再蛀入树皮,至11月中旬在原处化蛹越冬。 该虫喜为害树龄老、生长势差的银杏,适生于透光好、干燥的林分,但气候过于干旱,则影响幼虫化蛹。一般发生于每年平均温度14℃以上地区以及海拔800米以下的地区,我国虫口密度的分布由南向北逐渐减少。 对该虫的防治,在为害较轻地区,可摘除被害枝条,扫除落叶焚毁之。被害严重地区可在幼虫初龄时期,F280％敌敌畏乳剂水溶液1:800倍液喷洒被害枝,效果较好。防治已蛀入树皮内的幼虫,可以油雾剂(敌敌畏油剂、六六六高丙体,邻二氯苯,柴油混合液)喷洒树干,幼虫死亡率达100％。防治成虫羽化,可在3月下旬成虫将羽化前,在树干上涂刷涂白剂,效果很好。
Pammene sp. Infects ginkgo shoots with larvae, causing the shoots to die and reducing the yield of ginkgo. In Jiangsu strain was the highest rate of 100%, Zhejiang and other places Ginkgo production 80 to 90%. The insects of a year to pupa in the trunk of the lower cortex in winter, from late March to mid April emergence, adults need to add nutrients, spawning on the twigs, each female spawn more than 90 tablets, life expectancy of about 13 days. In early May hatch as larvae, the first instar larvae move lively, since the spur end moth into the branches, or from the middle of the growing branch or base insects, each larvae can damage spur 2, larvae in the branches about Food 25 days that leaves the leaf outside the leaves to move out of habitat, and sometimes eat a small amount of leaf meats, after about half a month and then bored into the bark, mid-November pupation in winter overwintering. The insect-hi age-old damage, poor growth potential Ginkgo biloba, suitable for good light, dry stand, but the climate is too dry, then affect larval pupation. Generally occurs in areas with average annual temperature above 14 ℃ and areas below 800m above sea level. The distribution of insect population density in China gradually decreases from south to north. The prevention and control of the insects, in less harmful areas, the removal of the victim branches, remove the leaves burned. Severe areas can be killed in the early stages of larvae, F280% dichlorvos emulsion solution 1: 800 times spraying the victim branches, the effect is better. Controlling larvae that have been bored into the bark can spray tree trunks with oil mist agents (Dichlorvos, HCH, O-dichloro-benzene, diesel oil), killing 100% of the larvae. Prevent adult emergence, adults may emerge in late March before the trunk brushing whitening agent, the effect is very good.