Morphometric and Agronomic Characterization of Tepary Bean (Phaseolus acutifolius A. Gray) Landraces and Identification of High-yielding Accessions Introduced in Burkina Faso

Abstract

Rainfed legume production in Burkina Faso is increasingly challenged by climatic variability. Diversifying grain-legume genetic resources may help address these constraints and support food security. Tepary bean (Phaseolus acutifolius A. Gray), a legume native to the south-western United States and northern Mexico, is tolerant of water stress, heat, and diseases. This crop may therefore provide an alternative for maintaining grain-legume production under erratic rainfall. This study evaluated the morphometric and agronomic characteristics of 36 tepary bean accessions introduced into Burkina Faso. The experiment was conducted over two consecutive years (2022 and 2023) at the Kamboinse research station using an alpha-lattice design with three replications. Fourteen quantitative traits were recorded using descriptors established by the International Board for Plant Genetic Resources. The results revealed morphometric and agronomic variability within the collection. Significant differences were observed among accessions and years, as well as for the accession × year interaction for selected traits. A strong positive correlation was observed between seed length and seed width. Plant height was the principal discriminating morphometric trait, whereas 100-seed weight and seed yield were the principal discriminating agronomic traits. Cluster analysis structured the accessions into three groups: Group II contained 16 accessions, Group I contained 12, and Group III contained eight. Accessions G40279 and G40173C from Group II showed high grain-yield potential and may be useful in breeding programmes targeting variable climatic conditions in Burkina Faso.