麦蒲螨对黑沙蒿主要害虫寄主选择行为研究

Studies on host selection behavior of Pyemotes tritici of Artemisia ordosica

麦蒲螨[Pyemotes tritici(LaGreze-Fossat et Montagne)]是黑沙蒿主要钻蛀性害虫沙蒿大粒象(Adosomus sp.)和沙蒿尖翅吉丁(Sphenopterasp.)的重要寄生性天敌。为明确麦蒲螨的寄主选择行为,本文分别研究了麦蒲螨对黑沙蒿4种钻蛀性害虫、同一寄主不同发育阶段、受害黑沙蒿根部以及害虫虫粪的选择行为。结果表明:麦蒲螨对4种害虫以及同种害虫不同龄期幼虫有明显的选择现象,其中,对沙蒿尖翅吉丁的趋向性相对最高,沙蒿蛀茎蛾次之,沙蒿大粒象相对较小;相对于寄主的初孵幼虫,麦蒲螨对其老熟幼虫和蛹的趋向性更为强烈;不同种类害虫幼虫对麦蒲螨的寄主定位起到重要作用,而不同种害虫的虫粪对麦蒲螨的寄主选择行为也有一定的作用。相比受害黑沙蒿而言,健康黑沙蒿对麦蒲螨有明显的驱避现象。研究结果为揭示麦蒲螨对黑沙蒿不同钻蛀性害虫的寄主偏好性,利用麦蒲螨进行黑沙蒿主要害虫的生物防治提供了理论依据。

Pyemotes tritici （Newport）is one of the important parasitoids of the woodborers such as Adosopius sp. and Sphenoptera sp.associated with Artemisia ordosica Krasch.The host selection behavior of P .tritici to 4 spe-cies of Artemisia ordosica woodborers,different larval stages,the roots of damaged A .ordosica and frass of Arte-misia ordosica woodborers was studied.The results showed that there was an obvious selection behavior of P .triti-ci to different types and ages of pest larvae.P .tritici preferred to parasitize Sphenoptera sp.,and it had a stron-ger tendency to parasitize mature larvae and pupae than newly hatched larvae.The types of pest larvae played an important role in the host location behavior of P .tritici ,and frass of different species of woodborers also had a role on the host selection of P .tritici .Compared with the victims of A .ordosica ,P .tritici obviously avoided the healthy A .ordosica .The results can provide a theoretical support for studying host selection behavior of 4 species of Artemisia woodborers and biocontrol applications of P .tritici .