感染马铃薯Y病毒烟株对烟蚜取食行为及烟蚜茧蜂适应性的影响

为探明烟蚜茧蜂Aphidius gifuensis Ashmead对烟蚜Myzus persicae(Sulzer)取食感染马铃薯Y病毒(Potato virus Y,PVY)烟株的适应性,利用刺探电位图谱(EPG)技术记录了烟蚜在感病烟株与健康烟株上的取食行为,并测定了烟蚜茧蜂对取食2种烟株烟蚜的寄生率以及烟蚜茧蜂的羽化率、发育时间及性比等指标。结果表明,与健康烟株相比,烟蚜在感染PVY烟株上的第1次刺探取食持续时间显著延长,且口针遇到阻力的次数(F波)和总持续时间均显著减少。烟蚜在感病烟株木质部的吸食时间(G波)显著长于健康烟株。感病烟株上烟蚜在韧皮部阶段的分泌唾液时间(E1波)较在健康烟株上显著缩短,而被动吸食汁液时间(E2波)显著延长。烟蚜茧蜂寄生取食感染PVY烟株的烟蚜,虽然能成功完成其生活史,但适应性与寄生取食健康烟株烟蚜的蚜茧蜂存在差异。在感染PVY烟株上,烟蚜茧蜂对烟蚜的寄生率为33.67%,显著低于对照的64.67%;且僵蚜体重明显下降,羽化的成蜂个体较小;成蜂存活时间1.48 d也极显著短于对照组的2.25 d。表明烟蚜茧蜂对取食感染PVY烟株烟蚜的适应性较低,PVY可通过烟蚜为介体间接降低烟蚜茧蜂的适应力。

Influence of Potato virus Y-infected tobacco on feeding behaviour of green peach aphid Myzus persicae (Sulzer) and on Aphidius gifuensis Ashmead adaptability

To elucidate the adaptability of Aphidius gifuensis Ashmead to Myzus persicae (Sulzer) which feeds on Potato virus Y (PVY)-infected tobacco, the probing behavior of the M. persicae, parasitized by A. gifuensis on healthy and PVY-infected tobacco were recorded by using electropenetrography (EPG). Additionally, the indexes of parasitism rate, emergence rate, developing time and progeny sex ratio of A. gifuensis on the healthy and infected tobacco plant were also explored. Compared with the control, the duration of the first probe in parasitized M. persicae on infected tobaccos was significantly prolonged and the number of F and the total duration of F waveforms were significantly reduced. The time of the actively sucking from xylem (G waveform) of M. persicae on infected tobaccos was significantly longer than the healthy tobacco, and the phloem phase compared with the healthy plant, the total duration of phloem sap ingestion (E1 waveform) of M. persicae on infected tobaccos was significantly shortened, whereas the duration in passive ingestion (E2 waveform) was significantly extended. Although A. gifuensis could complete their life cycle on M. persicae reared on infected tobacco, there were differences in adaptability of A. gifuensis comparing with the healthy plant. The parasitism rate of A. gifuensis to M. persicae on infected tobacco was 33.67%, which was lower than the control test (64.67%). The weight of mummy and the body size of newly emerged A. gifuensis adults on infected plants were both smaller than that on healthy tobacco. No significant difference was detected in progeny sex ratio of A. gifuensis both on healthy and infected treatments. The survival time of A. gifuensis adults on infected tobaccos was 1.48 d, which was significantly shorter than the control one (2.25 d). The study result showed the PVY infection has an adverse effect on A. gifuensis.