不同生境下泽兰实蝇的寄生状况及其影响因素分析

Analysis of the Parasitic Status of Procecidochares utili in Different Habitats and the Impact Factors

[目的]研究不同生境下泽兰实蝇的寄生状况及其影响因素。[方法]通过对云南大中山地区紫茎泽兰入侵生境中泽兰实蝇的寄生状况抽样调查,分别从环境因素和紫茎泽兰生长状况两方面,分析了影响泽兰实蝇寄生的因素。[结果]不同生境泽兰实蝇的寄生状况有显著差异,其中林区公路和林区空旷地寄生率、虫瘿数和虫瘿内幼虫数最高,显著大于华山松林和落叶阔叶林。乔木层盖度与泽兰实蝇的寄生率、虫瘿数、虫瘿重呈显著负相关,而灌木层盖度与泽兰实蝇的寄生率呈显著正相关。泽兰实蝇寄生率与紫茎泽兰均高和开花率均呈极显著的正相关。[结论]开阔的生境有助于泽兰实蝇的寄生和扩散,林下的光照条件对泽兰实蝇的寄生亦有影响。泽兰实蝇偏好寄生林区公路边和林区空旷地植株较大、分枝较多的植株,泽兰实蝇对花期的植株可能更具有趋性。

[Objective] The aim was to study the parasitic status of Procecidochares utili in different habitats and the impact factors.[Method] The factors that influenced the parasitic status of Procecidochares utilis were analyzed from two sides,environmental factors and growth conditions of Eupatorium adenophorum,based on a sampling survey in different habitats which Procecidochares utilis had invaded in Dazhongshan Mountain in Yunnan Province.[Result] The results showed that there were significant differences of the parasitic status in different habitats.The parasitic rate of Procecidochares utilis,number of zoocecida and the number of larva in zoocecida at roadside and open ground in forest areas were significantly higher than those in Pinus armandii forests and deciduous broad-leaved forests.It was found that the tree layer coverage was positively correlated with parasitic rate,number of zoocecida,weight of zoocecida,respectively,and the shrub layer coverage was positively correlated with parasitic rate.The results also showed that parasitic rate was positively correlated with average height of Eupatorium adenophorum and flowering rate.[Conclusion] Procecidochares utilis will better disperse and parasite in open microhabitats and the light conditions under the tree canopy will affect the parasitism of Procecidochares utilis.Procecidochares utilis prefers to lay eggs first on taller plants with more branches and tend to choose Eupatorium adenophorum in the blooming period.