Phytopathology. 2007 May;97(5):544-50. doi: 10.1094/PHYTO-97-5-0544.
ABSTRACT This study characterized resistance in pea lines PI 347295 and PI 378159 to Clover yellow vein virus (ClYVV). Genetic cross experiments showed that a single recessive gene controls resistance in both lines. Conventional mechanical inoculation did not result in infection; however, particle bombardment with infectious plasmid or mechanical inoculation with concentrated viral inocula did cause infection. When ClYVV No. 30 isolate was tagged with a green fluorescent protein (GFP) and used to monitor infection, viral cell-to-cell movement differed in the two pea lines. In PI 347595, ClYVV replicated at a single-cell level, but did not move to neighboring cells, indicating that resistance operated at a cell-to-cell step. In PI 378159, the virus moved to cells around the infection site and reached the leaf veins, but viral movement was slower than that in the susceptible line. The viruses observed around the infection sites and in the veins were then recovered and inoculated again by a conventional mechanical inoculation method onto PI 378159 demonstrating that ClYVV probably had mutated and newly emerged mutant viruses can move to neighboring cells and systemically infect the plants. Tagging the virus with GFP was an efficient tool for characterizing resistance modes. Implications of the two resistance modes are discussed.
摘要 本研究对豌豆品系 PI 347295 和 PI 378159 对三叶草黄脉病毒 (ClYVV) 的抗性进行了分析。遗传杂交实验表明，这两个品系的抗性均由单个隐性基因控制。常规机械接种不能引起感染；然而，用感染性质粒进行粒子轰击或用浓缩病毒接种物进行机械接种确实会引起感染。当 ClYVV No.30 分离物被绿色荧光蛋白 (GFP) 标记并用于监测感染时，两种豌豆品系中的病毒细胞间运动存在差异。在 PI 347595 中，ClYVV 在单细胞水平上复制，但不会移动到邻近细胞，表明抗性作用于细胞间步骤。在 PI 378159 中，病毒移动到感染部位周围的细胞并到达叶脉，但病毒的运动速度比敏感品系慢。在感染部位周围和叶脉中观察到的病毒随后被回收，并通过常规机械接种方法再次接种到 PI 378159 上，表明 ClYVV 可能已经发生突变，新出现的突变病毒可以移动到邻近细胞并系统感染植物。用 GFP 标记病毒是一种表征抗性模式的有效工具。讨论了两种抗性模式的意义。
