Abstract

The ability of an insect to vector a plant virus has traditionally been determined through controlled greenhouse transmission experiments that are notoriously resource- and time-consuming and of unreliable outcome. Therefore, before committing to these protracted experiments, it is important that researchers identify biologically viable candidate vectors. This study presents an approach for identifying potential insect vectors of circulative plant viruses that significantly reduces the time-to-results while also reducing costs and required resources. This artificial transmission protocol, using a buffered sucrose solution as the virus recipient in place of a living plant, also eliminates plant-to-plant variation in susceptibility to infection, allowing assessment of virus–insect compatibility required for successful transmission of persistent viruses. To validate this approach, species of hemipteran insects, including leafhoppers, froghoppers, aphids, sharpshooters, and treehoppers, were subjected to an artificial feeding system to determine their ability to vector the emerging Grapevine red blotch virus (GRBV) (family: Geminiviridae). Test insects were allowed to feed on a potted grapevine infected with GRBV for 3 days and then transferred to tubes containing the sucrose solution partitioned by a thinly stretched Parafilm™ membrane. After 3 days of feeding through the membrane, viruliferous test insects were stored for species identification and the sucrose solutions were tested by conventional polymerase chain reaction for the presence of GRBV DNA. Out of all the insects tested (n = 395) only nine treehoppers from two different species successfully transmitted GRBV to the sucrose solutions, indicating a high likelihood of vector capability, to be validated by greenhouse or field experiments.

摘要

传统上，昆虫携带植物病毒的能力是通过受控的温室传播实验来确定的，众所周知，这些实验非常耗费资源和时间，而且结果不可靠。因此，在进行这些长期实验之前，研究人员确定生物学上可行的候选载体非常重要。这项研究提出了一种识别循环植物病毒的潜在昆虫载体的方法，该方法显着缩短了获得结果的时间，同时还降低了成本和所需资源。这种人工传播协议，使用缓冲蔗糖溶液作为病毒受体代替活植物，也消除了植物对感染易感性的差异，允许评估成功传播持久性病毒所需的病毒-昆虫兼容性。为了验证这种方法，对包括叶蝉、蛙蝉、蚜虫、神枪手和树蝉在内的半翅目昆虫物种进行人工饲养系统，以确定它们对新兴昆虫的传播能力。葡萄红斑病毒（GRBV）（科：双生病毒科）。允许测试昆虫在感染了 GRBV 的盆栽葡萄藤上进食 3 天，然后转移到含有蔗糖溶液的试管中，该管由一层薄薄的 Parafilm™ 膜隔开。通过膜饲喂 3 天后，将带病毒的测试昆虫储存起来用于物种鉴定，并通过常规聚合酶链反应测试蔗糖溶液中 GRBV DNA 的存在。在所有测试的昆虫 ( n = 395) 中，只有来自两个不同物种的 9 只树蝉成功地将 GRBV 传播到蔗糖溶液中，表明载体能力的可能性很高，需要通过温室或田间实验进行验证。