INVOLVEMENT OF ABIOTIC STRESS TOLERANCE MECHANISMS IN BIOTIC STRESS TOLERANCE IN DURUM WHEAT

Abstract

The objective of our study is to implicate the mechanisms of tolerance to abiotic stress by the synthesis of metabolites in tolerance to biotic stress. The extracted metabolites; proline, sugars and polyphenols from durum wheat seedlings subjected to heat shock (40 °C), used to test antifungal activity on two fungal strains, powdery mildew and penicillium, under controlled conditions. The boussellam variety is more tolerant of applied stress than the Ciccio and Vitron varieties. The concentration of the three osmolytes varies from one variety to another; it increases in genotypes stressed compared to controls. Antifungal activity results in the appearance of an inhibition zone around the disc impregnated with the studied extract. Sugars have proven to be a highly effective antifungal agent compared to proline and polyphenols with maximum values (28,33 ± 2 mm) in oidium and (29 ± 1 mm) in penicillium.