Evaluation of Water Stress Tolerance in Advanced Breeding Lines of Durum and Bread Wheat Using 13C

摘要

Dry matter (DM),nitrogen uptake (TN) along with water (WUE) and nitrogen (15NUE) useefficiencies in twelve advanced breeding lines (ACSAD) and twovarieties (Cham1&6) of durum (DW) and bread (BW) wheat grown underwell water (I1) and water stress conditions (I2) were evaluated using sup15/supNand Δsup13/supC. Water stress decreased Δsup13/supC in allstudied genotypes. The extent of the decrease in Δ by stress wasrelatively higher in BW (-1.08‰) than DW (-0.8‰). Cham1 (DW) exhibitedthe highest DM, TN, NUE, WUE and Δsup13/supC values under I1,indicating its suitability to be grown under irrigated conditions.However, ACSAD1261 (DW) seemed to be a promising line to be grown insemi arid areas due to higher values in the aforementioned criteriaunder I2. For BW, the highest DM of ACSAD59 under I1 may suggest itssuitability to be grown under well irrigated conditions. However, DM ofACSAD883 and 1115 were not affected by watering regime. Additionally,due to the high DM of Cham6 and ACSAD1135 in both watering regimes, andbecause of the decrease in Δsup13/supC values under stress, it canbe suggested that they could be suitable for both irrigated and waterstress conditions. Since Δsup13/supC values were affected by wheatgenotype and watering regime as a result of the effects on the balancebetween stomatal conductance and carboxilation, it cannot be relied,completely, upon this technique to select drought tolerant genotypes.Therefore, we suggest that using Δsup13/supC along withagro-physiological parameters are better selection criteria for waterstress tolerance in breeding programs than when used separately.