释放花绒寄甲卵防治松褐天牛技术

Study on the Efficacy of Releasing Dastarcus helophoroides Eggs against Monochamus alternatus in Pine Forests

【目的】研究释放花绒寄甲卵对马尾松立木上松褐天牛的寄生效果,进一步探索经济有效利用花绒寄甲防治松褐天牛的技术措施。【方法】在林间设置直立木诱木,后在诱木上按5∶1、10∶1、15∶1(寄甲卵数量∶松褐天牛侵入孔数量)3个比例释放花绒寄甲卵卡防治松褐天牛以明确最佳释放比例。另在一年中6个不同时间释放花绒寄甲卵卡以明确最佳释放时期。此外,在江西省新干县金川镇林场6个小班释放花绒寄甲卵开展林间防治松褐天牛试验以明确大面积释放天敌的防治效果。【结果】释放卵与害虫数量比例为15∶1时的校正寄生率最高,室内为85.17%,林间校正虫口减退率为82.20%。3月上旬、3月下旬、4月上旬、4月下旬、8月上旬和10月下旬在马尾松诱木树干释放卵卡,以4月上旬防治效果最好,校正虫口减退率达82.37%。在林间每株直立诱木上释放4 000粒花绒寄甲卵,越冬代松褐天牛防治效果58.04%~87.39%。【结论】利用花绒寄甲卵防治松褐天牛具有良好的控制效果;江西中部地区释放花绒寄甲卵的最佳时间在4月上旬,偏南应提前约10天,而偏北地区则应推迟约10天。

[Objective]This study aims to evaluate the parasitic effects of Dastarcus helophoroides on Monochamus alternatus,and to explore the most cost efficient way to control the pest by the parasitoid. [Method]D. helophoroides eggs were released on the M. alternatus larvae and pupae of the infested bait-trees in pine forests with three ratios of the parasitoid and pest （5： 1、10： 1 and 15： 1） to study the best releasing rate,and released eggs in six different periods to research the best releasing period,and in addition,released eggs in six different plots in Jinchuan forestry station Xingan County of Jiangxi Province to study the control effects of M. alternatus by D. helophoroides eggs in large tracts of land.[Result] The result showed that when the D. helophoroides eggs were released at the ratio of 15： 1（eggs to beetle） on both the bait-tree logs in doors and the standing bait-trees in pine forests,the parasitic rate of D. helophoroides parasitic on M. alternatus was 85. 17% and 82. 20% ,respectively. In the field experiments,the eggs were released in early-March,late-March,early-April,late-April,early-August and late-October in Xingan County respectively,and it was found that there were significant differences in the parasitic rates and among the releasing times,and early-April was the best time,and the reducing rate of M. alternatus was 82. 37% . When mass releasing of eggs at a quantity of 4000 per bait-tree,the controlling effect of M. alternatus reached to 58. 04% - 87. 39% .[Conclusion] The result reveal that the releasing of D. helophoroides eggs is considerably effective to reduce M. alternatus populations,and the egg-releasing should be carried out in early April in the middle of Jiangxi province,and about 10 days earlier in the south and later in the north.