Biochemical changes in peanut genotypes submitted to moderate water stress

Five peanut genotypes, with different growth habits were submitted to Moderate water stress in a greenhouse for seven days. Seeds were planted in 15-litre pots containing soil and a substrate (Plantmax(R)), both optimized for the crop. The adopted experimental design was completely randomized, using a 5 x 2 bi-factorial scheme(5 genotypes x 2 water treatments) with five replications. The enzymatic activities of SOD, CAT, APX and GPX were analyzed, as well as the carbohydrate, starch and proline. An increased activity was shown in SOD and CAT enzymes for all genotypes submitted to water stress, in both leaf and root, especially in the 55 437 and BR1 cultivars and also in LBM Branco line. Proline accumulation and reduced starch were verified in all stressed genotypes, but carbohydrate content was increased just in tolerant materials. Based on results, 55 437 and BR1 were more tolerant to water stress, followed by LBM Branco. The LBR Branco shows intermediate behavior and LViPE- 06 was more sensitive.