Czosnek H, Kheyr-Pour A, Gronenborn B, Remetz E, Zeidan M, Altman A, Rabinowitch H D, Vidavsky S, Kedar N, Gafni Y
Hebrew University of Jerusalem, Faculty of Agriculture, Department of Field and Vegetable Crops, Rehovot, Israel.
Plant Mol Biol. 1993 Sep;22(6):995-1005. doi: 10.1007/BF00028972.
The leaf disc agroinoculation system was applied to study tomato yellow leaf curl virus (TYLCV) replication in explants from susceptible and resistant tomato genotypes. This system was also evaluated as a potential selection tool in breeding programmes for TYLCV resistance. Leaf discs were incubated with a head-to-tail dimer of the TYLCV genome cloned into the Ti plasmid of Agrobacterium tumefaciens. In leaf discs from susceptible cultivars (Lycopersicon esculentum) TYLCV single-stranded genomic DNA and its double-stranded DNA forms appeared within 2-5 days after inoculation. Whiteflies (Bemisia tabaci) efficiently transmitted the TYLCV disease to tomato test plants following acquisition feeding on agroinoculated tomato leaf discs. This indicates that infective viral particles have been produced and have reached the phloem cells of the explant where they can be acquired by the insects. Plants regenerated from agroinfected leaf discs of sensitive tomato cultivars exhibited disease symptoms and contained TYLCV DNA concentrations similar to those present in field-infected tomato plants, indicating that TYLCV can move out from the leaf disc into the regenerating plant. Leaf discs from accessions of the wild tomato species immune to whitefly-mediated inoculation, L. chilense LA1969 and L. hirsutum LA1777, did not support TYLCV DNA replication. Leaf discs from plants tolerant to TYLCV issued from breeding programmes behaved like leaf discs from susceptible cultivars.
采用叶盘农杆菌接种系统研究番茄黄化曲叶病毒（TYLCV）在感病和抗病番茄基因型外植体中的复制情况。该系统还被评估为番茄黄化曲叶病毒抗性育种计划中的一种潜在选择工具。将叶盘与克隆到根癌农杆菌Ti质粒中的TYLCV基因组头尾二聚体一起孵育。在感病品种（番茄）的叶盘中，接种后2 - 5天内出现了TYLCV单链基因组DNA及其双链DNA形式。烟粉虱在取食经农杆菌接种的番茄叶盘后，能有效地将TYLCV病害传播给番茄试验植株。这表明已产生了感染性病毒粒子，并已到达外植体的韧皮部细胞，昆虫可以从中获取病毒。从感病番茄品种的农杆菌感染叶盘再生的植株表现出病害症状，其TYLCV DNA浓度与田间感染的番茄植株相似，这表明TYLCV可以从叶盘转移到再生植株中。对烟粉虱介导的接种免疫的野生番茄物种智利番茄LA1969和多毛番茄LA1777的材料的叶盘不支持TYLCV DNA复制。育种计划中培育出的耐TYLCV植株的叶盘表现与感病品种的叶盘相似。
