RESPONSE OF Ty-RESISTANT TOMATO (Solanum lycopersicum) CULTIVARS TO BEGOMOVIRUSES AND THEIR GAS CHROMATOGRAPHY MASS SPECTROMETERY ANALYSIS

Abstract

Tomato (Solanum lycopersicum) production is affected by different diseases and Tomato yellow leaf curl virus (TYLCV) is the most prevalent and devastating begomovirus. Tyresistant cultivars were developed by Asian Vegetable Research and Development Center (AVRDC) Taiwan, using different combinations of Ty genes to observe pyramiding effects on resistance against various Begomoviruses. Cultivars containing Ty genes were grown in glass house at 65% relative humidity, 16 hours Dark and 8 hours Light, at 26 oC. At the age of 5 to 6 leaves, plants were exposed to viruliferous whitefly and were kept for ~40 days. Symptoms were observed every 10 days post exposure. Among nine Ty-resistant and one native (Nagina) cultivars, three were resistant i.e., R1, R6 and R9, two mild to moderately resistant i.e., R2 and R10, three i.e., R7, R8 and R14 very mild resistant while one Ty cultivar i.e., R15 along with susceptible (Nagina) variety showed no resistance. Nagina (susceptible) and R6 (resistant) cultivars were analyzed by Gas Chromatography Mass Spectrometry (GCMS). Among Ty cultivars (Ty-2, Ty-3 and Ty-5) genes harbouring cultivars showed better resistance and GCMS analysis lead to identification of bioactive compounds associated with resistant (R6) cultivar.