Article

Several barriers and challenges meet interspecific hybridization between taxa belonging to the genus Beta under Moroccan environmental conditions. Sugar beet (Beta vulgaris s. l.), is a socioeconomically important recent crop, developed mainly for the sugar production in Morocco. B. macrocarpa, a beet wild relative, is characterized by a wide genetic richness and high adaptative capacity. Obtaining viable hybrids from crosses between these two taxa is challenging. Hence, we studied 75 beet hybrids harvested on two cultivated (CH) and two wild (WH) parents separately. Twentyone effective agro-morphological traits were used as well as flux cytometry analysis to confirm the success of interspecific crosses. High phenotypic diversity was estimated both within and between hybrid groups. Plants of all WH hybrids and 50% of CH hybrids were rather similar to respective parents from the behavior and morphological points of views. The remaining CH hybrids were closer to their cultivated parent for phenotypical characteristics, vernalization requirement, and biannual vegetative cycle. Heritability rate in progeny generation was variable for cultivated and wild types, H2WP = 3-95% / H2CP = 3- 91% and of H2WP = 4-89% / H2CP = 3-89%. Diploid and tetraploid cytotypes were observed in hybrids and their parents. Tetraploid plants of Beta macrocarpa detected for the first time in Morocco provide novel insights on the cytogenetic diversity of Beta genus. The results obtained in this study show that Moroccan beet germplasm might provide a valuable reservoir of gene to improve genetic and cytogenetic diversity, adaptation and resistance to biotic and abiotic.