神农架松干蚧生物学的研究

华山松是我国亚热带西南部山地一种主要速生优良用材树种,集中分布在川、黔、滇以及秦巴山地。湖北省神农架和鄂西海拔800—2400m的地带,华山松林亦有较大面积的分布。湖北的华山松林除神农架近30万亩天然林外,其余大部分均系60年代引种营造的人工林,面积达100余万亩。长期以来,这些地方的华山松不断死亡,而近年来死亡现象日趋严重。据作者在神农架原始林区调查,华山松枯死株率达36％;而调查与之毗邻的巴东县绿葱坡人工纯林,枯死和濒死株率高达60％以上。如今不少地方不得不将未成材的华山松砍伐,而神农架原始林区的大量枯立木则任凭风吹雨打,病虫侵蚀而成为废物,经济损失巨大。自50年代起,国内不少学者和科技人员先后调查这一地区华山松的死因,但结果一直

STUDIES ON THE BIOLOGY OF MATSUCOCCUS SHENNONGJIAENSIS YOUNG ET LU (HOMOPTERA, MARGARODIDAE)

Matsucoccus shennongjiaensis Young et Lu, was found in sheng-nong-jia virginal forest area in westen-Hubei in 1986. It is the main factor causing out of larg quantity of Pinus armandi in this area.This pest has one generation a year, it overwinters as first stage nympha and egg (in a few cases). The nymphs suck sap from the trunks, causing rotting of cortex, flowing of resin, decline and death of the trees. The dying process can be acceraleted by the attack of the secondary pests such as bark beetle and so on.The damage in mixed forest is less than in the pure forest. The larvae of a Cecidomyiid eat eggs of this pest. It may be utilized as a biotic controlling agent of the pest.