INDUCTION OF MUTANTS IN DURUM WHEAT (TRITICUM DURUM DESF CV. SAMRA) USING GAMMA IRRADIATION

Abstract

A mutation breeding program was initiated in 2008 emphasizing the main constraints for sustainable production of durum wheat in Saudi Arabia. The aim of the program was to develop moderate or high yielding semi-dwarf/lodging tolerant, early maturing mutants with drought and disease tolerance from a local durum wheat cultivar (Triticum durum Desf. cv. Samra) which has the main defects of longer crop duration, lodging habit and low grain yield. Dry seeds of Samra were subjected to 150 and 200Gy doses of gamma irradiation and each treatment consisted of 2500 seeds. Irradiated seeds were grown as M1 population along with parental variety as control at Almuzahmiah Research Station of Riyadh, Saudi Arabia. Decrease in germination (%) and survival rate (%) of plants was observed. A wide variation in days to flowering and plant height was found in the M1 populations. Three seeds from each spike per plant of M1 plants were collected, bulked dose wise and grown separately as M2 in 2009 growing season. From these M2, 17 desirable putative mutant plants which varied significantly with the mother were visually selected. These putative mutants were found to be semi-dwarf and early maturing in nature with other improved agronomic traits including lodging reaction and grain yield. The selected plants, when grown in progeny lines as M3 in 2010, more or less maintained their superiority over the mother for many traits. Most of the mutant lines showed homogeneity for most of characters studied. Eleven of these 17 lines were found to be promising in respect of days to flower, plant height (for semi-dwarf) and other traits including grain yield.