Climatic Effects on Quality Parameters and Their Relationships of Bread Wheat Genotypes (Triticum aestivum L.) Grown under Semi-arid Region

Abstract

Aims: This study was conducted to determine climatic effects to quality parameters of bread wheat genotypes grown in the semi-arid region. Study Design: The experiment was carried out in a randomized complete block design with three replications. Thirty-three bread wheat genotypes (Triticum aestivum L.) were grown in a field trial and kernel samples analyzed for thousand kernel weight, test weight, protein content, wet gluten, dry gluten and SDS-sedimentation value. Place and Duration of Study: The research was carried out during the 2008 and 2009 growing seasons at Sanliurfa, Turkey. Methodology: For analyses 20 main spikes that contained fully developed kernels were chosen randomly from each plot and taken to the laboratory for analyses. The nitrogen content of kernels was determined using the Kjeldahl method and the result was multiplied by the factor 5.7 to calculate the protein content of kernels. Test weight and Sodium Dodecyl Sulphate (SDS)-sedimentation values were determined using standard procedures. Wet and dry gluten values were determined using a glutomatic system after separating gluten from the soluble starch and protein fractions. Results: Genotypes were significant (P ≤ 0.01) for all tested characteristics. Thousand kernel weight ranged from 25.8 to 42.3 g, test weight from 73.7 to 81.7 kg hl-1, protein content from 9.7 to 14.8%, wet gluten from 28.5 to 42.2%, dry gluten from 9.4 to 14.1% and SDS-sedimentation value from 19 to 39 ml. Bezostaya-I, Kutluk-94, Altay-85, Harmankaya-99, Lirasa, Kirgiz-95 and Dagdas-94 genotypes had the best quality among tested genotypes in the semi-arid climatic conditions. Protein content was positively correlated with wet gluten, dry gluten and SDS-sedimentation value, respectively. Relationships were significant between wet gluten and both dry gluten and SDS-sedimentation value. A positive significant correlation was found between thousand kernel weight and SDS-sedimentation value and between dry gluten and SDS-sedimentation value. Conclusion: Protein content, wet and dry gluten and SDS-sedimentation value were affected by climatic conditions of semi-arid region. Protein content, wet and dry gluten value were high but SDS-sedimentation value were low due to high temperature and low precipitation in semi-arid region.