Biological characterization of Tomato leaf curl New Delhi virus from Spain

Tomato leaf curl New Delhi virus (ToLCNDV; family Geminiviridae, genus Begomovirus) is an emerging virus in horticulture crops in Asia, and has recently been introduced in Spain, Tunisia and Italy. No betasatellite DNA was detected in infected tomato and zucchini squash samples from Spain, and agroinoculated viral DNA‐A and DNA‐B were sufficient to reproduce symptoms in plants of both crop species. Infected tomato and zucchini squash plants also served as inoculum sources for efficient transmission either mechanically or using Bemisia tabaci whiteflies. Cucumber, melon, watermelon, zucchini squash, tomato, eggplant and pepper, but not common bean, were readily infected using viruliferous whiteflies and expressed symptoms 8–15 days post‐inoculation. New full‐length sequences from zucchini squash and tomato indicated a high genetic homogeneity (>99% sequence identity) in the ToLCNDV populations in Spain, pointing to a single recent introduction event.     

Tomato leaf curl Oman virus and associated Betasatellite causing leaf curl disease in tomato in Pakistan

European Journal of Plant Pathology - The ongoing global spread of Tomato yellow leaf curl virus (TYLCV) poses an endemic threat to tomato production in all tropical and sub-tropical regions of the...     

番茄黄化曲叶病毒在湖北首次报道

2014年春季,在湖北省武汉市发现种植的番茄表现植株矮缩,叶片上卷,叶缘黄化等症状。PCR检测结果显示,所有采集的病样中均存在菜豆金色花叶病毒属病毒。进一步通过滚环扩增方法获得了该病毒的湖北分离物HB01的全基因组。基因克隆及序列分析结果表明,该病毒基因组全长为2 781nt,与已报道的番茄黄化曲叶病毒(TYLCV)各分离物同源性在89.0%以上,而与来自中国不同地区的TYLCV分离物的同源率均在97.0%以上。因此,HB01属于TYLCV的一个分离物。     

Screening Luffa germplasm and advanced breeding lines for resistance to Tomato leaf curl New Delhi virus

The two cultivated Luffa species can be severely infected by Tomato leaf curl New Delhi virus (ToLCNDV) with up to 100% yield loss. Here, 52 Luffa genotypes were screened for ToLCNDV resistance after natural field infection. Mean vulnerability index (VI) ranged from 0.00 to 75.33; genotypes IIHR-137 and IIHR-138 had no symptoms (VI 0), 16 genotypes were resistant (VI 0–25), 15 were moderately resistant (VI 26–50), and 19 were moderate to susceptible (VI?>?50). Ten of the most resistant genotypes and five susceptible checks were then challenge-inoculated using whiteflies or sap in an insect-proof net house; only IIHR-137 [L. cylindrica (L.) Roem.] was symptomless (VI 0.00), and 3–5% of plants of IIHR-138 [L. cylindrica (L.) Roem.] and IIHR-Sel-1 [L. acutangula (L.) Roxb.] had only mild symptoms; genotype Arka Prasan was most susceptible (VI 80.96). Asymptomatic plants were confirmed as infected using polymerase chain reaction. Susceptible genotypes rapidly developed leaf curling, then a severe mosaic 10 days post-inoculation. The resistant inbred lines identified are good candidates for a breeding program for ToLCNDV-resistant cultivars.

     

Diversity analysis of Tomato leaf curl New Delhi virus-[potato], causing apical leaf curl disease of potato in India

The complete coat protein (cp) gene sequence of eighty Tomato leaf curl New Delhi virus-[potato] (ToLCNDV-[potato]) isolates collected from eleven states were determined. Phylogenetic analysis based on cp gene grouped the isolates into two major clades (I & II) and they shared 95.9–100.0% identity. The DNA A and DNA B of eight representative isolates (six from clade I and two from clade II) were 2739–2740 and 2692–2694 nts long and shared 94.6–99.4% and 97.2–99.5% homology within the isolates, respectively. Among the eight isolates, the DNA A of two isolates (Clade II), GWA-5 and FAI-19 had 94.6–95.3% sequence identity to other six isolates and formed a sub-clade within the ToLCNDV-[potato] isolates. Similar grouping was also revealed with AC1 and AC4 genes of these eight isolates. The DNA A components shared more than 90.0% identity with the DNA A of ToLCNDV isolates from cucurbitaceous crops, tomato, bhendi, 89.0–90.0% with ToLCNDV-papaya isolates and 70.4–74.0% with other tomato leaf curl viruses. Hence, the begomovirus infecting potatoes are the ToLCNDV isolates, designated as ToLCNDV-[potato]. Whereas, the DNA B components shared 86.6–91.7% identity with ToLCNDV isolates from cucurbits, tomato and bhendi. Evidence for intra-species recombination was detected only in DNA A with a maximum of three events in GWA-5 and FAI-19 isolates. Analysis of cp gene, DNA A, iterons and recombination events clearly indicate that two groups of ToLCNDV-[potato] infects potato in India.     

警惕新德里番茄曲叶病毒在我国的传播和危害

新德里番茄曲叶病毒(tomato leaf curl New Delhi virus, ToLCNDV)是双生病毒科菜豆金色花叶病毒属病毒,由烟粉虱Bemisia tabaci以循环持久性方式传播,能对茄科和葫芦科等多种作物造成毁灭性的危害。近年来,ToLCNDV不断扩散蔓延至新的国家和地区。我国于2021年在浙江的温室番茄上发现了ToLCNDV的危害。本文综述了ToLCNDV的发生分布、基因组结构与进化、传播方式和寄主范围,提出了防范ToLCNDV在我国进一步传播和危害的防控建议。     

Potato apical leaf curl disease: current status and perspectives on a disease caused by tomato leaf curl New Delhi virus

Journal of Plant Diseases and Protection - Potato apical leaf curl disease (PALCD) caused by a unique bipartite virus [tomato leaf curl New Delhi virus (ToLCNDV)] has emerged as a global threat....