Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University,Ithaca, NY 14853-5904, United States.
Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University,Ithaca, NY 14853-5904, United States; USDA-ARS, Emerging Pests and Pathogen Research Unit, Ithaca, NY 14853-5904, United States.
Virus Res. 2017 Sep 15;241:116-124. doi: 10.1016/j.virusres.2017.06.023. Epub 2017 Jun 27.
In the past decade recombinant strains of Potato virus Y (PVY) have overtaken the ordinary strain, PVY, as the predominant viruses affecting the US seed potato crop. Aphids may be a contributing factor in the emergence of the recombinant strains, but studies indicate that differences in transmission efficiency of individual PVY strains either from single or mixed infections, although variable, are not generally significant. Multiple strains of PVY are present in all potato production areas and common in many potato fields. Therefore, it is likely that individual alate aphids moving through a potato field will sequentially encounter multiple strains as they "taste test" multiple potato plants while looking for a suitable host. This study examined the transmission likelihood and efficiency of three common PVY strains when acquired sequentially by individual aphids. Green peach aphids (Myzus persicae, Sulzer) were allowed a 2-3min acquisition access period (AAP) on potato leaves infected with PVY, PVY or PVY, followed by another 2-3min AAP on a second potato leaf infected with a different PVY strain before being transferred to healthy potato seedlings for a 24h inoculation access period. All possible combinations of the three strains were tested. Strain-specific infection of the recipient plants was determined by TAS-ELISA and RT-PCR 3-4wk post-inoculation. The recombinant strains, PVY and PVY, were transmitted more efficiently than PVY when they were sequentially acquired regardless of the order acquired. PVY and PVY were transmitted with similar efficiencies when they were sequentially acquired regardless of the order. The recombinant strains appear to preferentially bind to the aphid stylet over PVY or they may be preferentially released during inoculation. This may contribute to the increased incidence of the recombinant strains over PVY in fields or production regions where multiple PVY strains are detected.
在过去的十年中，重组马铃薯 Y 病毒（PVY）菌株已经超过了普通的 PVY 菌株，成为影响美国种薯作物的主要病毒。蚜虫可能是重组菌株出现的一个促成因素，但研究表明，来自单一或混合感染的个别 PVY 菌株的传播效率差异虽然不同，但通常并不显著。在所有的马铃薯生产区都存在多种 PVY 菌株，在许多马铃薯田中也很常见。因此，单个有翅蚜虫在马铃薯田中移动时，很可能会在“品尝测试”多个马铃薯植株以寻找合适的宿主时，依次遇到多种菌株。本研究检验了三种常见 PVY 菌株在单个蚜虫依次获得时的传播可能性和效率。绿桃蚜（Myzus persicae，Sulzer）在感染了 PVY、PVY 或 PVY 的马铃薯叶片上有 2-3 分钟的取食接触期（AAP），然后在另一片感染了不同 PVY 菌株的马铃薯叶片上再有 2-3 分钟的 AAP，然后转移到健康的马铃薯幼苗上进行 24 小时接种接触期。测试了所有三种菌株的可能组合。在接种后 3-4 周，通过 TAS-ELISA 和 RT-PCR 确定了受感植物的菌株特异性感染。重组菌株 PVY 和 PVY 无论获得的顺序如何，在依次获得时的传播效率都高于 PVY。重组菌株无论获得的顺序如何，其传播效率与 PVY 相似。重组菌株似乎优先与蚜虫的口针结合，而不是与 PVY 结合，或者在接种时可能优先释放。这可能是在检测到多种 PVY 菌株的田间或生产区域中，重组菌株比 PVY 更普遍的原因之一。
