Morphological Diversity in Amaranth Lines for Inclusion in the Benin Catalogue of Plant Species and Varieties (CaBEV)

Amaranth (Amaranthus spp.) is a highly nutritious indigenous vegetable crop in Africa, yet its cultivation remains limited in Benin due to various constraints, including the scarcity of high-quality seeds. This study aimed at to characterize nine new amaranth lines, selected as candidates for inclusion in the Beninese Catalogue of Plant Species and Varieties (CaBEV), using morphological markers. The experiment was conducted under irrigated conditions at the research station of the Vegetable Crops Program of the National Institute of Agricultural Research of Benin, following a Randomized Complete Block Design with three replications. Morphological characterization was performed according to the amaranth descriptor established by the International Union for the Protection of New Varieties of Plants (UPOV). Results indicated significant differences among the lines for several agro-morphological traits (P ≤ 0.05). In terms of productivity, the AM_NKGN line produced the highest fresh leaf biomass yield (20.92 t/ha), while the Vert_local line had the lowest yield (11.30 t/ha). Additional findings revealed that the ACNL, AVAM_1939, and NGURUMA lines were respectively distinguished by the largest collar diameter (29.87 mm), the highest number of branches (35.60) and the greatest plant height (189.84 cm). Notably, the Vert_local line matured the earliest, reaching physiological maturity 62 days after transplanting (DAT), while the AVAM-1939 line matured the latest (167 DAT). Hierarchical Ascendant Classification (HAC) analysis grouped the lines into three distinct categories. The first group, comprising seven lines, displayed similar yet less productive agro-morphological traits. The second group, represented by the NGURUMA line, was characterized by its large and broad leaves, while the third group, consisting solely of the AVAM-1939 line, showed a high average number of branches. These findings underscore the strong agro-morphological potential of the new candidate lines, supporting their suitability for inclusion in CaBEV. However, multi-location trials are recommended to further assess the genotype-environment interaction for the studied parameters