Reaction of some wheat cultivars to root rot disease caused by Cochliobolus sativus.
Eight wheat cultivars were tested for their reaction to Cochliobolus sativus isolates H22 (highly virulent) and H1 (weakly virulent) by sowing grains in pots filled with soil mixed with inoculum. Giza 155 was the most resistant cultivar. In a second experiment, effects of root exudates and root extracts of the tested cultivars were studied on the in vitro growth of C. sativus isolates. Fungal growth was stimulated by exudates and extracts of all of the cultivars, although the effects were greater for those of highly susceptible cultivars (Giza 163, Sohag 1, Sohag 2 and Sakha 8).