Histopathology for the Influence of CMV Infection on Tomato Cellular Structures

Abstract

Cucumber mosaic virus (CMV) causes wide-spread diseases that damage some crops worldwide. One strain of the virus was isolated from tomato plants grown in Kuwait designated CMV-KU1. This isolate was found to be associated with a benign viral satellite RNA, causing mild symptoms on infected tomato plants. Another isolate, CMV-16, a severe stunting strain that lacking viral satellite RNAs was used in a comparative study with the isolated mild strain of the virus CMV-KU1. The objectives of this study were to investigate the effects of the viral infection on tissues, cells and cellular organelles in test plants using Transmission Electron Microscopy (TEM), to determine the extent of infection and host-virus interactions, and to detect the damage caused by virus isolates on tomato compared with healthy test plants. Electron micrographs of ultra-thin sections proved the presence of the viral particles, aggregated virus particles resulted in the formation of viral crystalline bodies, chloroplast damage and malformation due to the infection caused by the virus in infected plant tissues. The viral infection caused a reduction in chloroplast number and size. As the infection progressed, chloroplasts were completely destroyed and the grana were disorganized and scattered into the cytoplasm that causes reduction in chlorophyll contents in plant tissues. Acknowleddgement: This research work was supported and funded by the University of Kuwait, College of Graduate Studies, the Research Adminstration project # YS07/10, and Nanoscopy Scientific Center (NSC) at Kuwait University, Kuwait