ANTIOXIDATIVE AND BIOCHEMICAL RESPONSES OF WHEAT TO DROUGHT STRESS

Drought stress is considered as an effective parameter in decreasing crop production. Present study was investigated to understand the effect of drought stress on wheat (Triticum aestivum) seedlings under controlled condition. The seeds of wheat were subjected to five levels of water potential. 0 MPa (as control) and -2, -4, -6 and -8 MPa (as treatments) and germination percentage, mean germination time, proline and sugar amounts, chlorophyll contents, maximum photochemical efficiency of PSII and electron transport rate (ETR) have been examined. In addition enzymatic and non-enzymatic response of wheat seedlings to drought have been explored. Germination percentage and mean germination time were affected by different osmotic potentials. The least germination percentage and MGT were obtained from -8 osmotic potential. Drought caused significant losses in relative water content. Total chlorophyll content was reduced in all studied treatments. Drought levels higher than -2 MPa resulted in significant decrease of FV/FM value. ETR, however, observed no significant changes in drought treated seedlings. MDA, AsA and GSH contents increased in relation to the drought period. Activities of enzymatic antioxidants, such as SOD, CAT, APX, POD and GR increased to manage the oxidative stress.