Some Physiological Parameters as Screening Tools for Drought Tolerance in Bread Wheat Lines (Triticum aestivam L.)

Two greenhouse experiments were carried out at the Institute of Biological Production Systems, Leibniz Universität Hannover, Germany during 2008/2009 and 2009/2010 growing seasons to study the influence of the osmotic adjustment (OA) capacity, relative water content (RWC) and specific leaf area (SLA) on tolerance to drought in 22 breeding lines, two parents and tolerant cultivar (Sahel 1) of bread wheat (Triticum aestivam L.) under drought conditions. Differences were seen in of the OA, RWC and SLA of the different genotypes. Mean over all of OA, RWC and SLA for breeding lines were -0.51 Mpa, 83.28% and 116.56 cm2g-1, respectively. Four of the breeding lines showed the greatest osmotic adjustment capacities, high RWC and good SLA values under drought stress conditions better than the tolerant cultivar. The heritability of OA, RWC and SLA was 0.56, 0.49 and 0.88, respectively. The results indicated that osmotic adjustment, as well as RWC and SLA could be used as screening tools for drought resistant bread wheat genotypes in the greenhouse. This study also demonstrated the appropriate greenhouse screening methodology in this regard.