Determination of Resistance of Locally Grown Tomato Varieties to Fusarium oxysporum f. sp. lycopersici in Jordan under Greenhouse Conditions

Local tomato cultivars were tested for resistance to Fusarium oxysporum f. sp. lycopersici. Twenty-four cultivars were inoculated with composite samples of fungal suspensions from race 1, race 2, and equal volumes of race 1 and race 2 isolates of Fusarium oxysporum f. sp. lycopersici using the standard root dip method. Under green house conditions, sixty percent of the inoculated varieties showed different levels of resistance to race 1; however, some of the resistant varieties under greenhouse conditions were susceptible in open field conditions, where fifty-four were resistant to the mixture of race 1 and race 2, but all varieties were susceptible to race 2. The effect of tomato growth stage at the time of infection with the vascular wilt fungus Fusarium oxysporum f. sp. lycopersici was investigated through inoculation of different growth stages of C32 tomato differential line with a composite sample of Fusarium oxysporum f.sp. lycopersici. The age of tomato plant played an important role in its ability to overcome the disease, and there were significant differences among plants inoculated soon after transplanting, one, two, and three weeks after transplanting, compared to plants inoculated four weeks after transplanting which did not show any significant differences from the non-inoculated control under experimental conditions