Performance of high-protein mutant lines of triticum aestivum (L.) under-arid conditions of Syria

The agronomical characters of nine high-protein mutant lines of T. aestivum produced by the IAEA were studied along with their mother line Mex22A and four local cultivars. The experiments were carried out under rainfed conditions in 1990 and 1991 in southern Syria. Statistical analysis revealed significant differences among the lines in all characters. Genotype by environment interaction was significant for all characters except for N yield. There was a negative correlation between grain nitrogen concentration (GNC) and yield. However, two of the check cultivars and seven mutant lines had similar yield to Mex22A with grater Gnc. The other two mutant lines, 5074M and E296, were very late in heading and were characterized by low yield with extremely high GNC. Spikes per square meter contributed most to grain yield followed by number of seeds per spike and lastly seed weight. SDS sedimentation test values were negatively correlated with GNC. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE) was used to assay for high molecular weight (HMW) gluten in protein subunits of the grain endosperm. The results showed the presence of HMW gluten in GluD1 subunits 2+12 in Mex22A and all IAEA genotypes. Check varieties L92-6, Buhuth 4 and Cham 2 contain the good quality allelic GluD1 subunits 5+10. Nevertheless, 4 of 9 IAEA mutant lines were characterized by having higher SDS sedimentation values due to the presence of Glu-B1 subunits 17+18 when compared to those that had subunits 7+8. (author), 20 Refs., 2 Figs., 6 Tabs