GENE EXPRESSION INDUCED IN FABA BEAN (Vicia faba L.) BY Orobanche crenata AND ITS IMPACT ON THE FIELD LEVEL

Twenty five faba bean (Vicia faba L.) genotypes were evaluated under broomrape (Orobanche crenata L.) natural infestation conditions for their growth and yield characteristics as well as the gene expression of some tolerance genes. Analysis of variance of the morphological traits revealed highly significant differences among the genotypes for all the morphological traits. The results of some yield related traits such as number of pods/plant, number of seeds/pod and number of seeds/plant were significantly increased in the Egyptian broomrape-tolerant genotypes “Giza843”, “Misr1” and “Misr3” and in the foreign genotype “FAB476”. On the other hand, “Nubaria1” genotype was worst genotype to defeat broomrape growth in which the highest number of O. crenata spikes/row and O. crenata spikes/plant was obtained (broomrape-susceptible genotypes). Cluster analysis of yield related traits distingweshed between broomrape tolerant and susceptible genotypes as well as between Egyptian and foreigner genotypes. Gene expression was assessed using Reverse Transcriptase PCR (RT-PCR) to study genes transcript accumulation during early (35 days) and late stages (50 days) of infestation. RT-PCR results revealed a kind of coexpression in common defense genes such as (HMG gene) and broomrape specific defense genes such as (C4H gene) in the most tolerant genotype “Misr1”. It is possible to conclude that yield related traits and the molecular results revealed that faba bean cultivar “Misr1” was the most broomrape tolerant cultivar and “Nubaria1” was the broomrape susceptible cultivar.