Variation in the resistance of some faba bean genotypes to Orobanche crenata

Four faba bean (vicia faba l.) genotypes were tested for their reaction to orobanche crenata forsk.,infestation. evaluation was carried out for two cropping seasons at the ariana research station,tunisia in a field naturally infested with o. crenata and in pot experiments. at maturity,the genotypes baraca,giza429 and the breeding line bader carried 2-6 times less of number of emerged parasites and 3-7 less of dry weight of emerged parasites than the susceptible cv. badï. the average yield observed for the three resistant genotypes was two to four-fold higher than the one observed for the susceptible genotype. these resistant genotypes seemed to flower earlier and to show late orobanche establishment which gave them an advantage over the parasite. the genotype bader,which was selected for its resistance to o. foetida,was resistant to o. crenata,showing that selecting for o. foetida resistance can protect against o. crenata infection. besides,the two genotypes baraca and giza429 selected for their resistance to o. crenata in spain and egypt respectively,do not present tubercle necrosis on their roots,showing that they do not respond similarly to the tunisian population of o. crenata. these partially resistant genotypes may provide breeders with additional sources of resistance to o. crenata,and can form appropriate material for an integrated control package.