Screening of vegetable cowpea [Vigna unguiculata (L.) Walp.] varieties introduced in Burkina Faso for Cowpea aphid-borne mosaic virus resistance

---

Résumé

Vegetable cowpea is a variant of cowpea where the pods are consumed at the
immature stage. Like other legumes, vegetable cowpea is subject to several
constraints including Cowpea Aphid-Borne Mosaic Virus (CABMV) which
seriously hampers its production. The objective of this study was to assess the
impact of CABMV on the growth of vegetable cowpea varieties. The experiment
was conducted in the greenhouse at the Kamboinsé experimental station and
consisted of an artificial infestation of twenty (20) varieties in pots with CABMV in
a randomized complete block design with three replications. At the end of the
infestation of seedlings, carried out one week after sowing, fourteen (14) quantitative
characteristics were measured. The study revealed the existence of several
discriminating resistance and agronomic parameters, thus translating the existence of
diversity within the varieties. Correlations were also observed between severity at
21th DAI and 30th DAI; between severity at 30th DAI and AUDPC; between
flowering and vegetable cowpea stage. Results of the multivariate analysis show that
the diversity of resistance and agro-morphological parameters is structured with a
division of varieties into three distinct groups based on the discriminating characters
namely the degree of disease severity and AUDPC. From this study, four (4)
varieties IT84S-2246, UG-CP-8, IT85F-2805-5, and Telma were resistant to
CABMV. Varieties IT85F-2805-5 and Telma expressed the best agro-morphological
performance and resistance to CABMV. The high variability for all traits shows
potential for breeding for vegetable cowpea improvement.

Mots-clés

vegetable cowpea, resistance, Cowpea Aphid-Borne Mosaic Virus, Burkina Faso.