Photosynthetic Apparatus and Biochemical Parameters in Tomato and Squash Crops Influenced by Cucumber Mosaic Virus (CMV) Infection

This study was aimed to compare the influence of two cucumber mosaic virus (CMV) strains (CMV‐KU1 and CMV‐16) on photosynthetic apparatus and different biochemical parameters with emphasis on carotenoids, fatty acids and phenolic compounds in both squash and tomato plants. Squash plants, infected with CMV‐16, showed a decrease in β‐carotene content with a concomitant increase in lutein by which the ratio of lutein/β‐carotene significantly increased by 62% (p<0.05) compared with the control plants. However, the change in lutein/β‐carotene ratio was less pronounced in tomato plants. In response to CMV‐16 infection, the desaturation index indicated by unsaturated/saturated fatty acids (UFA/SFA) increased in both squash and tomato plants, indicating that stress in test plants. Phenolic content in squash plants were significantly changed in response to CMV‐16 inoculation. In CMV‐16 infected squash plants, phenolic accumulation increased sharply indicating that plant tolerance for the viral infection. CMV‐16 in tomato had weaker impact on phenolic content compared with squash plants. This might be due to a possible involvement of symptom development and defense mechanisms due to plant‐virus interactions. All biochemical parameters studied were not significantly influenced in test plants infected with CMV‐KU1 compared with the severe CMV‐16. Satellite RNA in the CMV‐KU1 may have protected plants against infection caused by virulent strains. Our results indicated that CMV‐KU1 is benign to crops compared to the severe viral strain of CMV‐16. This research work was funded by the Research Administration (Research Project # YS01/14) and supported by the College of Graduate Studies, Univ. of Kuwait, Kuwait. Support or Funding Information Research Project # YS01/14, University of Kuwait, Kuwait College of Graduate studies, University of Kuwait