Expression of Defensive Genes Responsible for Direct and Indirect Defense Against Spider Mite Tetranychus urticae in Black Bean

Black bean genotypes have high resistance to the important pests and diseases of common bean. To evaluate the effectiveness of four genes in the direct (plant negatively effects on biology and reproduction of herbivore by its physical and biochemical barriers) and or indirect)by attracting natural enemies of herbivores(in black beans against two spotted spider mite, expression levels of these genes (Pathogenesis-Related Protein3 (pr3))Pathogenesis-Related Protein4¡ Lipoxygenase(pr4), Lipoxygenase (lox) and β-Ocimen Synthase(os() in two resistant black bean genotypes (KS1179 and KS 1115(( and susceptible control (Khomeini) before and after infection were determined by QRT-PCR technique. Based on the results of the study in all genotypes the gene expression of pr3 and PR4 involved in the direct defense, unregulated, although this increase in black bean genotypes was intensive than genotype Khomeini. Expression of os gene involved in indirect defense significantly increased in one of black bean genotypes (KS1179) however, the expression of this gene in another genotype of black beans and Khomeini did not change after the mite infestation. lox gene, which is involved in the direct and indirect defenses in both black bean genotypes after infection were significantly increased and decreased in Khomeini. Given that inhibition of lox genes in plant defense, can effect negatively on both direct and indirect defense. Thus, our results demonstrate on the importance of further study of this gene to increase resistance to spider mite in black bean.