Chung Bong Nam, Canto Tomas, Tenllado Francisco, Choi Kyung San, Joa Jae Ho, Ahn Jeong Joon, Kim Chun Hwan, Do Ki Seck
National Institute of Horticultural & Herbal Science, Rural Development Administration, Wanju 55365, Korea.
Centro de Investigaciones Biológicas, Centro de Investigaciones BiolÓgicas-Spanish National Research Council, Madrid 28040, Spain.
Plant Pathol J. 2016 Aug;32(4):321-8. doi: 10.5423/PPJ.OA.12.2015.0259. Epub 2016 Aug 1.
We examined the effects of temperature on acquisition of Potato virus Y-O (PVY-O), Potato virus A (PVA), and Potato leafroll virus (PLRV) by Myzus persicae by performing transmission tests with aphids that acquired each virus at different temperatures. Infection by PVY-O/PVA and PLRV increased with increasing plant temperature in Nicotiana benthamiana and Physalis floridana, respectively, after being transmitted by aphids that acquired them within a temperature range of 10-20°C. However, infection rates subsequently decreased. Direct qRT-PCR of RNA extracted from a single aphid showed that PLRV infection increased in the 10-20°C range, but this trend also declined shortly thereafter. We examined the effect of temperature on establishment of virus infection. The greatest number of plants became infected when N. benthamiana was held at 20°C after inoculation with PVY-O or PVA. The largest number of P. floridana plants became infected with PLRV when the plants were maintained at 25°C. PLRV levels were highest in P. floridana kept at 20-25°C. These results indicate that the optimum temperatures for proliferation of PVY-O/PVA and PLRV differed. Western blot analysis showed that accumulations of PVY-O and PVA coat proteins (CPs) were lower at 10°C or 15°C than at 20°C during early infection. However, accumulation increased over time. At 25°C or 30°C, the CPs of both viruses accumulated during early infection but disappeared as time passed. Our results suggest that symptom attenuation and reduction of PVY-O and PVA CP accumulation at higher temperatures appear to be attributable to increased RNA silencing.
我们通过对在不同温度下获取每种病毒的蚜虫进行传播试验，研究了温度对桃蚜获取马铃薯Y病毒O株系（PVY - O）、马铃薯A病毒（PVA）和马铃薯卷叶病毒（PLRV）的影响。在10 - 20°C温度范围内获取PVY - O/PVA和PLRV的蚜虫传播后，PVY - O/PVA和PLRV在本氏烟草和佛罗里达酸浆中的感染率分别随植物温度升高而增加。然而，感染率随后下降。对从单个蚜虫中提取的RNA进行直接定量逆转录聚合酶链反应（qRT - PCR）显示，PLRV感染率在10 - 20°C范围内增加，但此趋势随后也很快下降。我们研究了温度对病毒感染确立的影响。用PVY - O或PVA接种后，本氏烟草在20°C时感染的植株数量最多。佛罗里达酸浆植株在25°C时感染PLRV的数量最多。PLRV水平在保持在20 - 25°C的佛罗里达酸浆中最高。这些结果表明PVY - O/PVA和PLRV增殖的最佳温度不同。蛋白质免疫印迹分析表明，在早期感染期间，PVY - O和PVA外壳蛋白（CPs）在10°C或15°C时的积累低于20°C时。然而，积累量随时间增加。在25°C或30°C时，两种病毒的CPs在早期感染期间积累，但随着时间推移而消失。我们的结果表明，在较高温度下PVY - O和PVA症状减轻以及CP积累减少似乎归因于RNA沉默增强。
