Hanboonsong Y, Ritthison W, Choosai C, Sirithorn P
Department of Entomology, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002, Thailand.
J Econ Entomol. 2006 Oct;99(5):1531-7. doi: 10.1603/0022-0493-99.5.1531.
Sugarcane white leaf disease is caused by plant pathogenic phytoplasmas that are transmitted to the plant by the leafhopper Matsumuratettix hiroglyphicus (Matsumura). To determine whether there are other insect vectors that transmit this disease pathogen, leafhopper species in sugarcane, Saccharum officinarum L., fields in northeastern Thailand were monitored by using light traps. Sixty-nine leafhopper species from family Cicadellidae were found. Using nested polymerase chain reaction (PCR) with specific primers, a 210-bp amplified DNA fragment corresponding to phytoplasma associated with sugarcane white leaf disease was detected from 12 species of leafhoppers [Balclutha rubrostriata (Melichar), Balclutha sp., Bhatia olivacea (Melichar), Exitianus indicus Distant, Macrosteles striifrons Anufriew, Matsumuratettix hiroglyphicus (Matsumura), Recilia distincta (Motschulsky), Recilia dorsalis (Motschulsky), Recilia sp., Thaia oryzivora Ghauri, Yamatotettix flavovittatus Matsumura, and Xestocephalus sp.]. The percentage of individual infection with phytoplasma varied from 5% in B. olivacea to 35% in Xestocephalus sp. The most abundant leafhopper species, i.e., E. indicus, Y. flavovittatus, and M. hiroglyphicus were used in transmission tests to determine their vector status for the sugarcane white leaf phytoplasma transmission. Infected insects were reared on healthy plants and specific PCR followed by sequencing of the amplicons was used to determine whether the phytoplasma was transmitted to the plants. The results showed that both Y. flavovittatus and M. hiroglyphicus, but not E. indicus, can transmit sugarcane white leaf phytoplasma to healthy sugarcane plants. The transmission efficiency of M. hiroglyphicus (55%) was higher than that of Y. flavovittatus (45%). We conclude that Y. flavovittatus is a newly discovered vector for sugarcane white leaf disease, in addition to M. hiroglyphicus. These two species peak at different times of the year and therefore complement each other in the transmission of the phytoplasma. Because there are no known alternative host plants for the sugarcane white leaf, management of the disease will necessarily require the control of both Y. flavovittatus and M. hiroglyphicus.
甘蔗白叶病由植物致病性植原体引起，该植原体通过叶蝉黑尾大叶蝉（Matsumura）传播至植株。为确定是否存在其他传播这种病害病原体的昆虫媒介，利用灯光诱捕器对泰国东北部甘蔗（Saccharum officinarum L.）田中的叶蝉种类进行了监测。共发现了69种叶蝉科叶蝉。使用特异性引物进行巢式聚合酶链反应（PCR），从12种叶蝉[红纹巴尔叶蝉（Melichar）、巴尔叶蝉属、橄榄色巴蒂叶蝉（Melichar）、印度埃克叶蝉（Distant）、条纹角顶叶蝉（Anufriew）、黑尾大叶蝉（Matsumura）、显脉雷氏叶蝉（Motschulsky）、背脉雷氏叶蝉（Motschulsky）、雷氏叶蝉属、稻泰叶蝉（Ghauri）、黄带山叶蝉（Matsumura）和刻纹头叶蝉属]中检测到一个与甘蔗白叶病相关植原体对应的210 bp扩增DNA片段。感染植原体的个体比例从橄榄色巴蒂叶蝉的5%到刻纹头叶蝉属的35%不等。选取数量最多的叶蝉种类，即印度埃克叶蝉、黄带山叶蝉和黑尾大叶蝉进行传播试验，以确定它们作为甘蔗白叶植原体传播媒介的地位。将感染的昆虫饲养在健康植株上，并使用特异性PCR及扩增子测序来确定植原体是否传播至植株。结果表明，黄带山叶蝉和黑尾大叶蝉均可将甘蔗白叶植原体传播至健康甘蔗植株，而印度埃克叶蝉则不能。黑尾大叶蝉的传播效率（55%）高于黄带山叶蝉（45%）。我们得出结论，除黑尾大叶蝉外，黄带山叶蝉是甘蔗白叶病新发现的传播媒介。这两个物种在一年中的不同时间达到高峰，因此在植原体传播方面相互补充。由于甘蔗白叶病尚无已知的替代寄主植物，对该病害的防治必然需要同时控制黄带山叶蝉和黑尾大叶蝉。
