越冬代马尾松毛虫虫情调查方法比较

在湖南省洞口县、通道县、会同县共选取4个马尾松毛虫发生区设置标准样地并选择标准株,采用捆草绳、粘虫胶2种方式,调查越冬代下树马尾松毛虫幼虫数量。结果表明:不同的地点,下树越冬的幼虫数量不同,洞口县岩山乡试验林的虫口密度远大于通道县试验林的;不同的时间,下树越冬的幼虫数量差异明显。松毛虫幼虫进入树皮缝隙中越冬是一个缓慢的过程,在湖南,从10月下旬开始,进入树干树皮缝隙越冬,至12月初结束;下树幼虫数量最多的时段在11月9—16日。用捆草绳调查越冬幼虫的方法简易、成本低,且其数据较准确;用粘虫胶的调查方法则一目了然。

Comparison of investigation methods of overwintering Dendrolimus punctatus

Set the standard disirict to choose standard tree in four occurrence regions of Dendrolimus punctatus in Dongk- ou, Tongdao and Huitong of Hunan Province, the number of overwintering Dendrolimus punctatus larva was investigated u- sing methods of tying straw rope and sticky insect glue. The results showed that, the number of overwintefing larvae of Dendrolimus punctatus was different in different locations and time. The larvae of Dendrolimus punctatus getting into bark crack to overwinter was a slow process, which was from late October until early December in Hunan. The number of lar- vae under the tree in 9 - 16th November was the largest. The method of tying straw rope was simple, low cost and accu- rate , while the method of sticky insect glue was dear.