相思拟木蠹蛾为害西南桦的调查研究

Investigation on Lepidarbela baibarana on Betula alnoides

于广西百色市老山林场调查了相思木蠹蛾对西南桦的为害情况,并进行了不同高度虫孔数组内单因素方差分析、不同整枝方式虫孔平均数差异显著性检验、种群密度估计模型拟合研究。结果表明:西南桦有虫孔株率70%,虫孔密度2.79个/株;以2m为区间段,无虫孔的占74.8%,有1个以上虫孔的占25.2%;相思拟木蠹蛾对树干高度有选择性,树干4～6m间虫孔数最多;幼虫侵入期人工修枝会加重相思拟木蠹蛾为害;以无虫株率估计相思拟木蠹蛾种群密度的模型为^x=1.420 8(-lnP0)1.476 8。相思拟木蠹蛾为害对西南桦木材品质有较大影响,应加强监测防治技术研究。

The forest of Betula alnoides in Laoshan Forest Farm in Baise City of Guangxi was investigated to study the occurrence and damage of the Lepidarbela baibarana, a boring beetle of B. alnoides. The wormhole numbers at different heights were analyzed using oneway ANOVA. The results showed that the ratio of B. alnoides trees with wormholes was 70% , with a wormhole density of 2.79 wormholes per plant. L. baibarana was selective for the height of tree trunks. The wormhole number was maximum when the height above ground was 4--6 m. Artifi- cial pruning might deteriorate the invasion of larvae. The population density-estimated model was x=1. 420 8 （ ln P0 ）1.4768. In summary, the damage of L. baibarana is a serious problem to B. alnoides, the quality of which can be greatly affected. Research on prevention and control technology should be strengthened.