Amer Mahmoud Ahmed, Khalid Zaheer, Hussain Khadim, Al-Shahwan Ibrahim, Ali Al-Saleh Mohammed
Plant Protection Department, College of Food and Agriculture Sciences, King Saud University, P.O. Box 2460, Riyadh, 11451, Saudi Arabia.
Cell Mol Biol (Noisy-le-grand). 2024 Nov 27;70(11):58-63. doi: 10.14715/cmb/2024.70.11.8.
During the field visits in growing season of 2022 in Dammam Region of Saudi Arabia, begomovirus-like symptoms including leaf curling, leaf cupping, leaf distortion, vein thickening and reduced leaf size were observed in squash and cucumber fields. Twenty-five samples were collected from each crop and PCR amplification was done using general diagnostic begomovirus primers (AC-1048/AV-494 and Begomo I/Begomo II). The obtained results showed desired sized amplified DNA fragments (550 bp and 1.1 kb) according to the primer sites. Sequencing results were analyzed using BLAST and revealed the presence of three different bipartite begomoviruses which include Squash leaf curl virus (SqLCV) isolated from squash and cucmber, Watermelon chlorotic stunt virus (WmCSV) and Tomato leaf curl Palampur virus (ToLCPalV) isolated from squash. The highest nucleotide identity found was 99.4% with Egyptian SqLCV isolated from squash and the lowest similarity was 93.3% found with a USA isolate isolated from wheel cactus. Sequencing results of two isolates of WmCSV showed 100% sequence identity with each other, eight isolates from Palestine isolated from watermelon, two isolates from Mexico isolated from prickly pear cactus and Watermelon, one isolate from each Lebanon and Jordan isolated from melon and wild mustard respectively. The lowest identity (87%) was found with a Saudi Arabian isolate isolated from papaya. For ToLCPalV isolate showed the highest identity (100 %) with an already reported isolate of same virus from melon in Saudi Arabia and two isolates isolated from cucumber and cantaloupe in Iran. However, the lowest identity (95.3%) was found with an Indian isolate isolated from eggplant. This is the first investigation of complex viral disease caused by SqLCV, WmCSV and ToLCPalV on the basis of molecular characterization from squash and a SqLCV isolate from Cucumber in Saudi Arabia.
2022年生长季节在沙特阿拉伯达曼地区进行实地考察期间，在南瓜和黄瓜田中观察到了类似双生病毒的症状，包括叶片卷曲、叶片杯状、叶片扭曲、叶脉增厚和叶片尺寸减小。从每种作物中采集了25个样本，并使用通用的双生病毒诊断引物（AC-1048/AV-494和Begomo I/Begomo II）进行了PCR扩增。获得的结果显示，根据引物位点，扩增出了预期大小的DNA片段（550 bp和1.1 kb）。使用BLAST对测序结果进行分析，发现存在三种不同的双分体双生病毒，其中包括从南瓜和黄瓜中分离出的南瓜叶卷曲病毒（SqLCV）、西瓜褪绿矮化病毒（WmCSV）以及从南瓜中分离出的番茄叶卷曲帕拉姆布尔病毒（ToLCPalV）。发现的最高核苷酸同一性为99.4%，与从南瓜中分离出的埃及SqLCV相同，最低相似性为93.3%，与从轮状仙人掌中分离出的美国分离株相同。WmCSV的两个分离株的测序结果显示彼此具有100%的序列同一性，来自巴勒斯坦的八个分离株分别从西瓜中分离得到，两个来自墨西哥的分离株分别从刺梨仙人掌和西瓜中分离得到，一个来自黎巴嫩的分离株从甜瓜中分离得到，一个来自约旦的分离株从野生芥菜中分离得到。与从木瓜中分离出的沙特阿拉伯分离株的最低同一性为87%。对于ToLCPalV分离株，与沙特阿拉伯已报道的来自甜瓜的同一病毒分离株以及从伊朗黄瓜和哈密瓜中分离出的两个分离株具有最高同一性（100%）。然而，与从茄子中分离出的印度分离株的最低同一性为95.3%。这是首次基于沙特阿拉伯南瓜和黄瓜中SqLCV分离株的分子特征，对由SqLCV、WmCSV和ToLCPalV引起的复杂病毒病进行调查。
