Effects of Cucumber Mosaic Virus infection and drought tolerance of tomato plants under greenhouse conditions: Preliminary results

In nature, plants are simultaneously exposed to a combination of biotic and abiotic stresses limiting their yield, and thus, it is useful evaluating effects of biotic and abiotic stresses on plant growth and development. Here, a combination effect of drought stress and Cucumber mosaic virus (CMV) infection were investigated on some physiological traits of tomato plants under greenhouse conditions. Two levels of CMV infection (infected and non-infected) and four drought stress (100% Field capacity (FC), 80% FC, 60% FC and 40% FC) were used as treatments to set a factorial experimental design. After two weeks, systemic infection of CMV and some physiological traits including the relative water content (RWC), electrolyte leakage (EL), chlorophyll and carotenoid contents were measured. Results showed that combination of CMV and drought stress delayed appearance of drought symptoms. Both infected and non-infected plants showed the lowest RWC, total chlorophyll, carotenoid and the highest EL observed in 40% FC, which may be related to effectiveness of drought on CMV. Since drought stress ameliorated the sign of CMV infection, it is concluded that there is a correlation between abiotic and biotic stresses improving tolerance level of this tomato variety.