Comparison of resistance to drought of three bean cultivars

The aim of the present work was to evaluate oxidative stress and plant antioxidant system of three bean genotypes in response to drought. Drought was imposed 14 d after emergence until the leaf relative water content reached 65%. Water stress increased lipid peroxidation (LPO), membrane injury index, H2O2 and OH production in plant leaves. Activities of superoxide dismutase and ascorbate peroxidase (APOX) increased significantly in all the studied cultivars, whereas catalase (CAT) increased in cvs. Plovdiv 10 and Prelom, but decreased in cv. Dobrudjanski ran. Cv. Plovdiv 10 which had the highest APOX and CAT activities also showed the lowest increase in H2O2 and OH productions as well as in LPO, whereas cv. Dobrudjanski ran showed the lowest increases (and often the lowest values) in enzyme activities and the highest increase in LPO, H2O2 and OH productions. In conclusion, cvs. Plovdiv 10 and Prelom were drought tolerant, whereas cv. Dobrudjanski ran was drought sensitive.