Comparative reproduction of the stunt nematode,Tylenchorhynchus latus and its role on some broad bean stocks in Egypt

Twenty broad bean, Vicia faba L., stocks were evaluated under clay field conditions, pH 8.1, located at the Western Experimental Station of the Faculty of Agriculture, Cairo University, Giza for their relative susceptibility against the stunt nematode, Tylenchorhynchus latus and other tylenchids. Statistical differences (p???0.05 and 0.01) in the studied stocks are found in either final nematode populations or the plant growth and yield components. The potential of each stock to support build-up of the stunt nematode or other tylenchids was estimated in relation to that of L 99 stock or L 348, respectively, which were regarded as check stocks and the host category based on the potential reproduction index of each cultivar was estimated. In this respect, the studied stocks could be categorised for their susceptibility against T. latus as follow: L 241 stock only was rated as resistant to the nematode. L 31 stock was observed to be less susceptible. Twelve stocks of broad bean out of twenty were graded as moderately susceptible. On the other hand, only six broad bean stocks namely L 99, G 429, L 92, L 24, L 13 and L 46 were categorised as highly susceptible (HS). It is worth noticed that reproduction of nematode was favoured on HS and susceptible cultivars but suppressed on resistant one. So, all evaluated stocks showed great variability in their reaction to the nematode infection based on the host type. Also, various plant growth and yield components of broad bean stocks were also discussed. Eventually, the differences among the tested cultivars should serve as a good resource for plant breeders and cropping systems to limit the loss due to the nematode infection.