Seed yield and chemical composition of durum wheat under arid and semiarid Mediterranean environments

Seed chemical composition of wheat is modified by cultivar and environment. This study was conducted to investigate the relationships between seed protein, lipid, sugars and starch content of durum wheat with seed yield of twenty two durum wheat cultivars. The experiments were carried out under rainfed conditions at an arid and semiarid locations in Northern Jordan. Statistical analysis revealed significant differences among the cultivate in all characters. Location by cultivar interaction was significant for all characters except for sucrose content. Durum wheats grown at the semiarid location exhibited higher seed yield and the lower protein, lipid, glucose, fructose and sucrose contents than those grown at the arid location. There were a negative correlations between seed protein and lipid contents and seed yield. Seed starch content was positively correlated with seed yield. However, the cultivars Genil-3, Korifla,Omsinma-1 and Stork had similar seed yields with varied seed chemical constituents. In addition, the cultivar Wadalmez-5 was characterized by the lowest yield and highest starch content among all cultivars. These results might suggest that factors other than seed yield were also important in determining the chemical composition of seeds and that one-sided selection for high seed yield tends to reduce the nutritional quality of durum wheat seeds.