Hoyle Victoria J, Wunsch Anna O, McLane Heather, Browning Scottie, Flasco Madison T, Cieniewicz Elizabeth J, Fuchs Marc
Section of Plant Pathology and Plant-Microbe Biology, School of Integrative Plant Science, Cornell University, Geneva, NY 14456, USA.
Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA.
Viruses. 2025 Sep 20;17(9):1274. doi: 10.3390/v17091274.
Grapevine red blotch virus (GRBV), the causal agent of red blotch disease of grapevines, is transmitted by , the threecornered alfalfa hopper. Isolates of GRBV belong to two phylogenetic clades (I and II) and is a dimorphic insect, with two genotypes found in the western (California, CA) and the southeastern (SE) regions of the United States. The transmission of GRBV by is circulative and nonpropagative, yet some parameters of transmission remain to be characterized. Here, we compared the acquisition, transmission, and retention of GRBV isolates from phylogenetic clades I and II by males and females of the two genotypes. Results indicated that the SE genotype acquired GRBV more efficiently (72.5%, 29/40) than the CA genotype (22.5%, 18/80), with differences in acquisition observed between males (32.5%, 26/80) and females (52.5%, 21/40) of the two genotypes and between GRBV isolates of phylogenetic clades I (29%, 23/80) and II (60%, 24/40). Following acquisition, both genotypes and sexes retained GRBV isolates of phylogenetic clades I and II for at least 60 days without access to an infected plant. For transmission, the GRBV isolate of phylogenetic clade II was more efficiently transmitted by the SE genotype (54%, 13/24) than the CA genotype (17%, 4/24) and SE females (75%, 12/16) were significantly more efficient transmitters of GRBV than CA females (19%, 3/16). Together, our findings revealed that genotype, sex, and virus isolate influence GRBV acquisition and transmission but not retention. This research addressed important knowledge gaps in -mediated transmission of GRBV that are essential for advancing red blotch disease epidemiology and developing appropriate disease management responses.
葡萄红斑点病毒（GRBV）是葡萄红斑点病的病原体，由三叶苜蓿叶蝉传播。GRBV分离株属于两个系统发育分支（I和II），而三叶苜蓿叶蝉是一种二态昆虫，在美国西部（加利福尼亚州，CA）和东南部（SE）地区发现了两种基因型。GRBV由三叶苜蓿叶蝉进行循回非增殖性传播，但一些传播参数仍有待确定。在这里，我们比较了两个基因型的雄性和雌性三叶苜蓿叶蝉对系统发育分支I和II的GRBV分离株的获取、传播和留存情况。结果表明，SE基因型获取GRBV的效率（72.5%，29/40）高于CA基因型（22.5%，18/80），在两个基因型的雄性（32.5%，26/80）和雌性（52.5%，21/40）之间以及系统发育分支I（29%，23/80）和II（60%，24/40）的GRBV分离株之间观察到获取情况存在差异。获取病毒后，两个基因型和性别的三叶苜蓿叶蝉在没有接触感染植物的情况下，都将系统发育分支I和II的GRBV分离株留存了至少60天。对于传播而言，系统发育分支II的GRBV分离株由SE基因型（54%，13/24）传播的效率高于CA基因型（17%，4/24），并且SE雌性（75%，12/16）传播GRBV的效率显著高于CA雌性（19%，3/16）。总之，我们的研究结果表明，基因型、性别和病毒分离株会影响GRBV的获取和传播，但不影响留存。这项研究填补了三叶苜蓿叶蝉介导的GRBV传播方面的重要知识空白，这对于推进红斑点病流行病学研究和制定适当的病害管理应对措施至关重要。
