Damayanti T A, Alabi O J, Hidayat S H, Crosslin J M, Naidu R A
Department of Plant Protection, Faculty of Agriculture, Bogor Agricultural University, Bogor 16680, Indonesia.
Department of Plant Pathology, Irrigated Agriculture Research and Extension Center, Washington State University, 24106 N. Bunn Road, Prosser, WA 99350.
Plant Dis. 2014 Feb;98(2):287. doi: 10.1094/PDIS-07-13-0745-PDN.
Potato (Solanum tuberosum) is an important vegetable crop in Indonesia. A small survey was conducted for virus diseases in November 2011 in Lembang, West Java, as part of assessing the sanitary status of potatoes produced in farmers' fields. Among the six potato fields surveyed, one field had nearly 20% of plants displaying stunted growth with leaves showing mild chlorotic spots and reduced size of lamina. Tubers harvested from symptomatic plants showed no necrosis symptoms. Symptomatic leaves from three representative potato plants were positive for Potato virus Y (PVY) when tested with PVY-specific immunostrips (Agdia Inc., Elkhart, IN). Leaf samples from virus-positive plants were imprinted on FTA Classic Cards (Whatman International Ltd., Maidstone, UK), air dried, and shipped to Washington State University for confirmatory diagnostic tests. Total nucleic acids were eluted from FTA cards (1) and subjected to reverse transcription (RT)-PCR using primers (PVY/Y4A and PVY/Y3S) specific to the coat protein (CP) of PVY (3). Nucleic acid extracts from samples infected with PVY ordinary strain (PVY), tuber necrosis strain (PVY), tobacco veinal necrosis strains (PVY and PVY), and a recombinant strain (PVY) were included as standards to validate RT-PCR assays. The approximately 480-bp DNA fragment, representing a portion of the CP, amplified in RT-PCR was cloned into pCR2.1 (Invitrogen Corp., Carlsbad, CA). DNA isolated from four independent recombinant clones was sequenced from both orientations. Pairwise comparison of these sequences (GenBank Accession Nos. KF261310 to 13) showed 100% identity among themselves and 93 to 100% identity with corresponding sequences of reference strains of PVY available in GenBank (JQ743609 to 21). To our knowledge, this study represents the first confirmed report of PVY in potato in West Java, Indonesia. Studies are in progress to assess the prevalence of PVY in other potato-growing regions of Indonesia and document the presence of different strains of the virus (2). Since the majority of farmers in Indonesia plant seed selected from their previous potato crop, there is an increased risk of primary and secondary spread of PVY through the informal seed supply system, leading to its increased significance to potato production in Indonesia. Therefore, strengthening foundation seed potato and supply chain programs will promote the production of virus-free potatoes in Indonesia. References: (1) O. J. Alabi et al. Plant Dis. 96:107, 2012. (2) A. Karasev and S. M. Gray. Am. J. Potato Res. 90:7, 2013. (3) R. P. Singh et al. J. Virol. Methods 59:189, 1996.
马铃薯（Solanum tuberosum）是印度尼西亚一种重要的蔬菜作物。2011年11月，在西爪哇省的伦邦开展了一项关于病毒病的小型调查，作为评估农户田地里所产马铃薯卫生状况的一部分。在所调查的6块马铃薯田中，有一块田地里近20%的植株生长发育不良，叶片出现轻度褪绿斑点，叶片面积减小。从有症状的植株上收获的块茎未表现出坏死症状。用马铃薯Y病毒（PVY）特异性免疫试纸条（Agdia公司，印第安纳州埃尔克哈特）检测时，来自3株有代表性马铃薯植株的有症状叶片对PVY呈阳性反应。将病毒阳性植株的叶片样本印在FTA Classic卡（Whatman国际有限公司，英国梅德斯通）上，风干后运往华盛顿州立大学进行确诊诊断检测。从FTA卡上洗脱总核酸(1)，并使用针对PVY外壳蛋白（CP）的特异性引物（PVY/Y4A和PVY/Y3S）进行逆转录（RT）-PCR(3)。将感染PVY普通株系（PVY）、块茎坏死株系（PVY）、烟草脉坏死株系（PVY和PVY）以及重组株系（PVY）的样本核酸提取物作为标准品，用于验证RT-PCR检测方法。RT-PCR扩增出的约480bp DNA片段，代表CP的一部分，被克隆到pCR2.1（Invitrogen公司，加利福尼亚州卡尔斯巴德）中。从4个独立的重组克隆中分离出的DNA进行双向测序。这些序列的两两比较（GenBank登录号KF261310至13）显示，它们之间具有100%的同一性，与GenBank中PVY参考株系的相应序列具有93%至100%的同一性（JQ743609至21）。据我们所知，本研究是印度尼西亚西爪哇省马铃薯中PVY的首次确诊报告。目前正在开展研究，以评估PVY在印度尼西亚其他马铃薯种植区的流行情况，并记录该病毒不同株系的存在情况(2)。由于印度尼西亚的大多数农民种植的种子是从他们之前的马铃薯作物中挑选出来的，PVY通过非正式种子供应系统进行初次和二次传播的风险增加，这使其对印度尼西亚的马铃薯生产具有更大的重要性。因此，加强基础种薯和供应链项目将促进印度尼西亚无病毒马铃薯的生产。参考文献：(1) O. J. Alabi等人，《植物病害》96:107，2012年。(2) A. Karasev和S. M. Gray，《美国马铃薯研究杂志》90:7，2013年。(3) R. P. Singh等人，《病毒学方法杂志》59:189，1996年。
