Indian Council of Agricultural Research-National Institute of Biotic Stress Management, Raipur, Chhattisgarh, India.
Plant Dis. 2023 Oct;107(10):2924-2928. doi: 10.1094/PDIS-06-22-1473-SC. Epub 2023 Oct 11.
Yellow mosaic disease of (L.) Thouars (CsYMD) was observed in up to 46% of plants in the mungbean, urdbean, and pigeon pea fields from 22 districts of Chhattisgarh State, India, during 2017 to 2019. The symptoms were characterized by yellow mosaic on green leaves and yellow discoloration of leaves in advanced stages of the disease. Severely infected plants showed shortened internodal length and reduced leaf size. CsYMD was transmissible to healthy and by whitefly (). The infected plants developed typical yellow mosaic symptoms on their leaves within 16 and 22 days of inoculation, respectively, suggesting a begomovirus etiology. Molecular analysis revealed that this begomovirus has a bipartite genome composed of DNA-A (2,729 nucleotides) and DNA-B (2,630 nucleotides). Sequence and phylogenetic analyses revealed that the nucleotide sequence of the DNA-A component had the highest identity of 81.1% with DNA-A of Rhynchosia yellow mosaic virus (RhYMV; NC_038885), followed by mungbean yellow mosaic virus (MN602427; 75.3%). DNA-B had the highest identity of 74.0% with DNA-B of RhYMV (NC_038886). As per ICTV guidelines, this isolate had <91% nucleotide identity with DNA-A of any of the begomoviruses reported; so, it is proposed as a new begomovirus species, tentatively named yellow mosaic virus (CsYMV). After agroinoculation with DNA-A and DNA-B clones of CsYMV, all plants developed leaf curl symptoms along with light yellowing symptoms 8 to 10 days after inoculation (DAI), while ∼60% of the plants developed yellow mosaic symptoms similar to those observed in the field 18 DAI, thus fulfilling Koch's postulates. From these agro-infected plants, CsYMV was transmissible to healthy plants by . Apart from these hosts, CsYMV also infected and caused symptoms in mungbean and pigeon pea.
2017 年至 2019 年，在印度恰蒂斯加尔邦的 22 个地区，在绿豆、乌豆和鸽豆田中观察到高达 46%的 植株感染了 (L.) Thouars 的黄化花叶病（CsYMD）。其症状表现为绿叶上的黄化花叶和病害后期叶片的黄化变色。受严重感染的植株表现出节间缩短和叶片变小。CsYMD 可通过粉虱（）传播给健康的 和 。接种后 16 天和 22 天，受感染的植物叶片上分别出现典型的黄化花叶症状，表明该病由双生病毒引起。分子分析表明，这种双生病毒具有由 DNA-A（2729 个核苷酸）和 DNA-B（2630 个核苷酸）组成的二分体基因组。序列和系统发育分析表明，DNA-A 组分的核苷酸序列与 Rhynchosia yellow mosaic virus（RhYMV；NC_038885）的 DNA-A 具有最高的 81.1%同一性，其次是绿豆黄化花叶病毒（MN602427；75.3%）。DNA-B 与 RhYMV 的 DNA-B（NC_038886）具有最高的 74.0%同一性。根据 ICTV 指南，该分离物与任何已报道的双生病毒的 DNA-A 的核苷酸同一性<91%；因此，提议将其作为一种新的双生病毒种，暂定名为 黄化花叶病毒（CsYMV）。用 CsYMV 的 DNA-A 和 DNA-B 克隆进行农杆菌接种后，所有 植株在接种后 8 至 10 天（DAI）出现卷叶症状和轻微黄化症状，而约 60%的 植株出现与田间观察到的类似的黄化花叶症状 18 DAI，从而满足科赫假设。从这些农杆菌感染的 植株中，CsYMV 可通过 传播给健康的 植株。除了这些宿主外，CsYMV 还感染和引起绿豆和鸽豆发病。
