介体条沙叶蝉传播小麦蓝矮病植原体特性研究

A study on the characteristics of wheat blue dwarf phytoplasma transmitted by leafhopper Psammotettix striatus

小麦蓝矮病植原体（wheat blue dwaH，WBD）属于翠菊黄化组三叶草绿变亚组植原体（16Sr I—C），由介体条沙叶蝉（Psammotettix striatus L）专化性传播。通过电镜超微结构观察，在接种小麦、长春花和带毒条沙叶蝉体内有大量植原体，而在健康植物组织、无毒条沙叶蝉和带毒条沙叶蝉所产卵中未见植原体的存在。通过介体传毒试验和PCR检测发现，条沙叶蝉最适获毒期为7d，植原体在虫体内的潜育期为15～17d，接毒期为2～3d。条沙叶蝉一旦获毒可终生持毒和传毒。不同虫态的条沙叶蝉带毒率没有明显的差异，但寄生植物的种类影响其带毒率。

Wheat blue dwarf （WBD） phytoplasma is a plant-pathogenic mollicute belonging to the 16SrI-C genetic group which is disseminated by Psammotettix striatus L.. Phytoplasmas were observed in the phloem sieve elements of wheat and periwinkle leaf tissues and the hind intestine of P. striatus L. under electron microscope but no phytoplasmas were found in healthy plants, viruliferous P. striatus L. and eggs of viruliferous P. striatus L. Based on transmission experiments and phytoplasma-specific polymerase chain reaction （PCR） assays, it was found that the acquisition access period （AAP） of the vector was 7 days. The latent period （LP） in the vector ranged from 15 to 17 days after the start of the acquisition and the inoculation access periods （IAPs） were 2 to 3 days. In general, the infectivity of the vector lasted for a life. The life stage of the vector is not critical to WBD acquisition, but host-plant species influenced WBD acquisition.