Effect of Cucumber mosaic virus Infection on Certain Mineral Elements, Vitamin C, Carbohydrates and Enzymes of some Tomato Cultivars

Abstract

This study aimed to test the response of certain components in tomato plants against Cucumber mosaic virus (CMV) and to understand the impact of the infection on the content of some mineral elements (calcium, potassium, and phosphorus), vitamin C, carbohydrates, and enzymes (peroxidases and catalases), as well as the amino acid proline in tomato fruits for ten tomato cultivars. The study was conducted in the Plant Viruses Laboratory and plastic greenhouses, Plant Protection Department at the College of Agriculture, University of Karbala, during the growing season 2022-2023. The results of sensitivity testing for the ten cultivars used in the study showed that sensitivity varies among different cultivars. Some cultivars, namely Madena, Zenga, and Joleen, demonstrated lower sensitivity (44.44%, 46.66%, and 50% respectively) compared to certain cultivars classified as highly sensitive to CMV, such as Heba and Bayan, with sensitivity values of 88.88% and 100% respectively. The results showed that viral infection had a clear effect on reducing the levels of calcium and phosphorus in the cultivars infected with CMV. The Basmah and Heba cultivars were the most affected, with levels reaching 28.10 mmol.L-1 and 1.92 mmol.L-1, respectively. These levels were significantly different from their levels in non-infected plants, which were 44.30 mmol.L-1 and 3.22 mmol.L-1, respectively. Furthermore, viral infection also had a significant impact on reducing the levels of carbohydrates and vitamin C, with rates of 27.03% and 6.62 mg g-1 FW (fresh weight), respectively. On the other hand, the levels of potassium, peroxidases, catalases, and the amino acid proline increased in the cultivars infected with CMV, reaching levels of 79.93 ppm, 11.53 U.mL-1, 1.47 U.mL-1, and 62.4 μg ml-1, respectively. These levels were significantly different from those in non-infected plants, which were 45.57 ppm, 4.49 U.ml-1, 0.63 U.ml-1, and 28.6 μg ml-1, respectively.