不同地区不同寄主植物上孤雌桃蚜及不同蚜型桃蚜共生菌的多样性

为了解桃蚜Myzus persicae共生菌动态变化的影响因素,利用诊断PCR、通用引物PCR及PCR-DGGE技术检测不同地区、不同寄主植物、不同蚜型桃蚜体内共生菌的种类,并用诊断PCR技术测定桃蚜体内次生共生菌的感染率。结果显示,不同地区、不同寄主植物、不同蚜型桃蚜体内初生共生菌布赫纳氏菌Buchnera aphidicola的16SrRNA基因序列高度一致。不同地区相同寄主上孤雌桃蚜体内次生共生菌的种类和感染率均不相同。同一地区不同寄主上孤雌桃蚜体内次生共生菌的种类和感染率略有差异。桃树上不同蚜型桃蚜体内次生共生菌种类有很大差异,孤雌蚜、雌性蚜和雄蚜未感染次生共生菌,卵和干雌分别感染杀雄菌Arsenophonus和沃尔巴克氏菌Wolbachia,干母感染沙雷氏菌Serratia symbiotica和杀雄菌。表明寄主植物、地理位置和生殖方式都影响桃蚜体内次生共生菌的感染模式,不同蚜型间次生共生菌菌群变化更大。

Diversity of endosymbionts in viviparous females of Myzus persicae (Hemiptera: Aphidicae) collected on different host plants from distinct regions in China and in different morphs collected on peach trees

To clarify the influencing factors of endosymbiont dynamics in Myzus persicae, diagnostic PCR with specific primers, PCR with universal primers and PCR-denatured gradient gel electrophoresis (PCR-DGGE) were used to detect the type of endosymbionts in viviparous females of M. persicae collected on different host plants from distinct regions in China and in different morphs collected on peach trees, and the diagnostic PCR was utilized to examine the infection frequencies of the secondary endosymbionts (S-endosymbionts) in M. persicae. The results showed that the partial sequences of 16S rRNA gene of Buchnera aphidicola, the primary endosymbionts in all samples showed high similarity among different morphs, regions and host plants. As for the viviparous females collected on the same host plants, the types and infection frequencies of S-endosymbionts were different among regions. The types and infection frequencies of S-endosymbionts of the viviparous females had little differences in different host plants from the same region. The S-endosymbionts were greatly different among aphid morphs. The viviparous females, oviparous females and males did not harbor S-endosymbionts. Arsenophonus was detected in overwintering eggs. Wolbachia was screened in fundatrigeniae, and both Serratia symbiotica and Arsenophonus were found in fundatrices. The results indicated that the factors involving host plant, geographical location and reproductive mode could affect the infection dynamics of S-endosymbionts in M. persicae, among which morphs had greater impact on the infection patterns of S-endosymbionts.