Identification of some mutants of durum wheat with high performance under natural drought conditions

摘要

Based on parameters of adaptation to water deficit, mutants from radiated seeds of 14 local varieties of durum wheat were observed in an "augmented design" for their qualitative and quantitative traits. The stability of morphological (plant height, leaf color, spike color, flag leaf area and spike vigor) and phenological (precocity) characteristics expressed at the second mutant generation (M2) remained for 109 out of the 437 entries studied in M3. Some of the mutants showed more than one adaptation characteristic to water stress. Direct selection based on grain yield over one year characterised by winter and spring droughts with 73 mm of rainfall over the January-May period made it possible to identify thirteen mutants, four of which were significantly (p<0.05) superior to all tested partents. The new mutants performance is essentially associated to: i) the number of reproductive tillers/plant, ii) the number of spikelet/spike; and iii) the number of vegetative tillers/plants that explain 79.4% of yield variance.