银杏超

The insect appears to be widely distributed in the Provinces of Jiangsu, Anhui, Zhejian, Guangxi etc. where ginkgo trees grow, doing damage to twigs and young branches, thus seriously impairing the growth of the tree and the yield of seeds.It is now known that each insect takes a whole year to pass through one life-cycle and that the pest mature at the end of March or in the first fortnight of April and lay their eggs between the second half of April to early May. The pests do serious damages to ginkgo trees from mid-April to late June at the larva stage after they are hatched from eggs. In mid-November, they begin to turn into pupae to survive the winter.Elderly trees or those growing with less vigor are liable to such insect attacks. The insect has a preference for light rather than darkness, a dry corner than m ist ones. The incidence of infestation decreases with higher latitudes. Vertical distributions have been discerned and the pest has not been found as yet in areas over 800 metres above sea level. As regards the method of preventing the insect attack, use 80% DDVP emulsion diluted with 800 times as much water to spray the leave portions and use DDVP oil spray to kill larvae in tree branches and twigs. Whitewash tree trunks to stop the eclosion of adult insects.     

几种非洲木材害虫及其杀灭方法

<正>由于我国工农业生产的发展和四化建设的需要,进口木材的品种和数量有较大的增加,同时也带进了一些我国原来没有的木材害虫,如不及时加以研究和妥善处理,将会给我国木材工业带来严重危害。 1984年,江苏省从象牙海岸进口了一万多立方米杂原木,发现虫害严重。为此我们对这几种害虫的杀灭方法进行了研究处理,防止了外来害虫的扩散蔓延,并挽回经济损失300多万元人民币。     

樱桃虎天牛和栎粉蠹的研究

<正> 刺槐是江苏、山东沿海地区造林的主要树种之一,它具有耐盐、速生、丰产、材质坚实等优点。但砍伐后的木材和制成的家俱、建筑材料及其它加工制品,极易遭受樱桃虎天牛和栎粉蠹虫蛀危害,有的当年即被虫蛀。被害木材经害虫反复蛀蚀后就不堪使用。这不仅给生产、生活用材造成大量损失,而且直接挫伤了群众栽植刺槐的积极性。故刺槐木材防蛀问题,已成为江苏北部林业生产上重要课题之一。为了遏止刺槐木材害虫的危害,我们于1973-1977年在江苏北部射阳县苗圃等地区进行对害虫的生活史观察和防治方法的研究,初步掌握了害虫的发生规律和一些比较有效的防治方法。     

银杏超小卷叶蛾(Pammene sp.)初步研究

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。