Phenotypic Diversity in Durum Wheat Landraces and Cultivars from Morocco and North America

Studying the phenotypic diversity of landraces and older advanced cultivars, along with their distribution, is important for breeding and germplasm conservation. To this sense, we analyzed the phenotypic diversity and spreading of 108 durum wheat accessions, including 56 landraces (LANs), 15 Moroccan cultivars (MCs), and 37 North American cultivars (NACs), using thirteen phenotypic descriptors. The collection studied was phenotypically very diverse (Shannon-Weaver index, H'mean=0.66). Spike color (H'mean=0.95), glume hairiness and spike waxiness (H'mean=0.89), peduncle attitude (H'mean=0.82), awn color (H' mean=0.75), and spike density and grain color (H'mean= 0.73) were the most diverse traits. The results also showed that NACs (H'mean=0.78) and the LANs (H'mean=0.69) were more diverse than MCs (H'mean=0.53). Multiple correspondence analyses explained 19.31% of the total variability and demonstrated a clear distinction between genotypes of Morocco and North America and between the LANs and MCs. These results of phenotypic diversity and distribution of studied genotypes can make a major leap forward in national breeding programs and germplasm collection expeditions.