Authors: JuYeon Yoon BongNam Chung SeungKook Choi
Publish Date: 2011/09/24
Volume: 156, Issue: 12, Pages: 2173-2180
Abstract
Since temperature effects on cucumber mosaic virus CMV have not been extensively studied we examined the effects of a moderate increase in temperature on the virulence and the genetic diversity of CMV in Nicotiana tabacum cv Samsun NN Two passage lines were initiated by inoculation of tobacco plants with a chlorosis strain of CMV designated FFMCMV derived from fulllength infectious CMV clones Symptom changes in the tobacco plants were monitored during five successive passages at 25 and 33°C At the fifth passage tobacco plants inoculated with FFMCMV at 33°C showed typical chlorosis symptoms at 7 days postinoculation dpi and the plants further developed mosaic symptoms on the upper leaves at 20 dpi In contrast tobacco plants inoculated with FFMCMV at 25°C did not show changes in symptoms on the upper leaves within 20 days Sequence analysis of the coat protein CP genes of FFMCMV revealed that a variety of spontaneous sequence changes were generated from the 14th and the 18th leaves of 33°C lineage tobacco plants but not from those of 25°C lineage tobacco plants The major CP mutation from the upper leaves of 33°C lineage tobacco plants was an L129P mutation indicating a change in symptoms correlating to the population composition of the mutant viruses Although relatively low mutation rates were observed from 33°Clineage tobacco plants some CP mutations may have been selected for systemic movement of CMV at the higher temperature providing evidence for the importance of temperature in the process of genetic diversification of CMV populationsThis research was supported by a research professorship program through the National Research Foundation of Korea NRF funded by the Ministry of Education Science and Technology MOEHRDKRF2007359F00001 and the GM crop development program of the BioGreen21 program Project no PJ007984032011 RDA
Keywords: