CARACTÉRISATION PHÉNOTYPIQUE ET GÉNOTYPIQUE DES GÉNOTYPES DE BLÉ DUR (Triticum durum)

Abstract

This study was carried out at the Sidi El Aidi Experimental Station during the 2020/2021 agricultural campaign and at the INRA / ICARDA Biotechnology laboratory, with the main objective of studying the genetic diversity of 8 Moroccan genotype and 42 exotic genotype of durum wheat (Triticum durum Desf.) on the basis of agro-morphological characters (date of heading, habit and height of the plant, length of the ear, length of the spurs in relation to the length of the ear, shape of lower glume shoulder, width of lower glume shoulder, length of lower glume beak, hairiness of outer surface of lower glume, color of dewclaws, shape of brush bristles etc.) in following the UPOV protocol for Distinctness, Uniformity and Stability (DUS) testing and followed by analysis of microsatellite markers. The results obtained showed the existence of a substantial diversity in the exotic genotype compared to the Moroccan genotype. On the basis of these results, similarity matrices were generated using the agro-morphological characters and Jaccard genetic distance matrix using the polymorphism of 8 microsatellite markers. These matrices were used to generate dendrograms, in order to estimate the genetic relationships between genotype. Our results suggest that agro-morphological characterization all the genotype can be distinguished among themselves. However, microsatellite analysis can distinguish certain genotype and are useful for the identification of this genotype. In addition, microsatellite loci detected substantial diversity in the collection (allelic range: 2-5; genetic diversity: 0.7556). However, the collection of exotic durum wheat revealed slightly greater genetic diversity at microsatellite loci (allelic range: 2-5; genetic diversity: 0.7392), compared to Moroccan durum wheat genotype (range: 2-4; genetic diversity: 0.72). The eight markers used in this study reveal dissimilarity between groups. Therefore, additional microsatellite markers are needed to distinguish all genotype. The present results on agro-morphological characters are of great importance for varietal identification, distinctness, uniformity and stability (DUS) when registering durum wheat genotype. Information on genetic distance and genetic diversity is also important for durum wheat breeding.