落叶松八齿小蠹防治与分析研究

Study on the Control and Analysis of Ips subelongatus

落叶松是我国东北方的主要造林树种。落叶松八齿小蠹在落叶松人工林的危害日益加剧,发生面积虽大小不一,但其共同特征是在林内呈团状分布;由于八齿小蠹繁殖速度快,成活率高,因而种群数量在短期内迅速增长,同时其各虫态均在树皮下隐蔽生活,加之林场内害虫的独特性,给防治带来了一定困难,不但危害树木,还对森林经营造成重大损失。为有效防治落叶松八齿小蠹,在对其生物学特性及发生规律等进行了解的基础上,本试验在落叶松人工林内拉样方并采用"五点法取样"选受害木喷药进行对照研究,结果表明:对样地内选取的受害木采用5%氯氰菊酯喷药处理后,害虫死亡率达到97.97%;分别将防治前后受害木上落叶松八齿小蠹害虫数量按等距法分5级,发现防治前Ⅱ级、Ⅲ级受害木所占比例最高;防治后Ⅰ级受害木所占比例最高。

Larch is the main afforestation tree species in Northeast China. Ips subelongatus hazards in larch plantations growing,although the occurrence area is different, but the common feature is a cluster of distribution in the forest ;the Ips s ubelongatus is propagation speed, high survival rate, so population in the short term rapid growth, also its instar were in the bark hidden life, coupled with the uniqueness of forest pest in,which to control brought certain difficulties, not only harm the trees, but also caused significant loss on forest management. For the effective prevention and treatment of Ips subelongatus.On the basis for understanding the biological characteristics and occurrence regularity, the test in larch plantation pull plots and the ＂five point sampling＂ of the chosen victim wood spraying were studied. The results showed that ：the damaged woods were spray treated with 5% cypermethrin ,pest mortality reached 97.97% ;The paddy of before and after treatment is respectively divided into five grades by distance method,found that before treatment the grade Ⅱ and grade Ⅲ accounted for the higher proportion;after treatment grade Ⅰ accounted for the highest proportion.