Sandra Nagamani, Mandal Bikash
Seed Pathology Laboratory, Division of Seed Science and Technology, Indian Agricultural Research Institute, New Delhi, India.
Advanced Centre for Plant Virology, Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi, India.
Front Plant Sci. 2024 May 14;15:1376284. doi: 10.3389/fpls.2024.1376284. eCollection 2024.
Begomoviruses (family ) are known for causing devastating diseases in fruit, fibre, pulse, and vegetable crops throughout the world. Begomoviruses are transmitted in the field exclusively through insect vector whitefly (), and the frequent outbreaks of begomoviruses are attributed largely due to the abundance of whitefly in the agri-ecosystem. Begomoviruses being phloem-borne were known not be transmitted through seeds of the infected plants. The recent findings of seed transmission of begomoviruses brought out a new dimension of begomovirus perpetuation and dissemination. The first convincing evidence of seed transmission of begomoviruses was known in 2015 for sweet potato leaf curl virus followed by several begomoviruses, like bhendi yellow vein mosaic virus, bitter gourd yellow mosaic virus, dolichos yellow mosaic virus, mungbean yellow mosaic virus, mungbean yellow mosaic India virus, pepper yellow leaf curl Indonesia virus, tomato leaf curl New Delhi virus, tomato yellow leaf curl virus, tomato yellow leaf curl Sardinia virus, and okra yellow mosaic Mexico virus. These studies brought out two perspectives of seed-borne nature of begomoviruses: (i) the presence of begomovirus in the seed tissues derived from the infected plants but no expression of disease symptoms in the progeny seedlings and (ii) the seed infection successfully transmitted the virus to cause disease to the progeny seedlings. It seems that the seed transmission of begomovirus is a feature of a specific combination of host-genotype and virus strain, rather than a universal phenomenon. This review comprehensively describes the seed transmitted begomoviruses reported in the last 9 years and the possible mechanism of seed transmission. An emphasis is placed on the experimental results that proved the seed transmission of various begomoviruses, factors affecting seed transmission and impact of begomovirus seed transmission on virus circulation, outbreak of the disease, and management strategies.
双生病毒科病毒以在全球范围内导致水果、纤维、豆类和蔬菜作物的毁灭性病害而闻名。双生病毒在田间仅通过昆虫介体烟粉虱传播，而双生病毒的频繁爆发很大程度上归因于农业生态系统中烟粉虱数量众多。已知双生病毒通过韧皮部传播，不会通过受感染植物的种子传播。双生病毒种子传播的最新发现揭示了双生病毒持久存在和传播的新层面。2015年首次有确凿证据表明甘薯卷叶病毒可通过种子传播，随后还有几种双生病毒，如黄秋葵脉花叶病毒、苦瓜黄花叶病毒、长豇豆黄花叶病毒、绿豆黄花叶病毒、绿豆黄花叶印度病毒、辣椒黄叶卷曲印度尼西亚病毒、番茄卷叶新德里病毒、番茄黄化曲叶病毒、番茄黄化曲叶撒丁岛病毒和秋葵黄花叶墨西哥病毒。这些研究揭示了双生病毒种子传播特性的两个方面：（i）在受感染植物的种子组织中存在双生病毒，但子代幼苗未表现出病害症状；（ii）种子感染成功将病毒传播给子代幼苗并导致发病。双生病毒的种子传播似乎是宿主基因型和病毒株特定组合的特征，而非普遍现象。本综述全面描述了过去9年报道的可通过种子传播的双生病毒以及种子传播的可能机制。重点阐述了证明各种双生病毒种子传播的实验结果、影响种子传播的因素以及双生病毒种子传播对病毒循环、病害爆发和管理策略的影响。
