Evaluation of Resistance Some Eggplant (Solanum melongena L.) Genotypes to Verticilium wilt (Verticillium dahliae) Disease under Greenhouse Conditions

Eggplant (Solanumm melongena L.) is grown in most areas of Iran, but Verticillium wilt (Verticillium dahliae) causes complete wilting in different stages of growth, particularly during flowering and fruit production. There has been little success in controlling the disease by application of fungicides. Therefore, resistance of some eggplant genotypes was evaluated in this study. First the fungal isolates from different areas of Tehran province were collected and purified. Purification, pathogenicity test of isolates was conducted using root dip method, on Varamini susceptibe cultivar, in spore suspension. Microsclerotium production was carried out in a liquid medium. The microsclerotia obtained was mixed at 20, 25, 30, 35, 40, 45 and 50 microsclerotium per gram of soil, and seedlings were transplanted at two leaf stage. Disease severity index was calculated using 1-7 scoring scale. The results showed that 24 microsclerotia per gram of soil is required to cause 50% of the disease severity on susceptible eggplant genotype. The Resistance of 20 genotypes and varieties was assessed 35 days post inoculation using fungal spore suspension. Evaluation of eggplant genotypes showed that four genotypes including Hyb.Valentina14102, Hyb. Aro14701, Valentina -1 and Bj30 with disease severity index ranging from 31.5 to 49.7 percent identified as the tolerant group which showed 50 percent increase in fruit, root and shoot weight compared to susceptible genotypes.