Evaluation of Genotypes of Some Cowpea (Vigna unguiculata (L.) walp) Varieties for Resistance to Thrips (Megalurothrips sjöstedti) in Burkina Faso

Abstract

Aims: Cowpea (Vigna unguiculata (L) Walp.) is one of the most important grain legumes grown in all arid and semi-arid zones of Africa. Its production helps to combat malnutrition and poverty, and contributes to food self-sufficiency. However, its production comes up against numerous abiotic and biotic constraints, including floricultural insects such as thrips (Megalurothrips sjöstedti), which are small insects. They belong to the order Thysanoptera, family Thripidae, and cause considerable damage to cowpea crops, especially at flowering time. The aim of this study was to evaluate the behavior of eight lines from Burkina Faso compared with the thrips-resistant line (TVx3236) from the IITA collection (Nigeria). Methodology: A completely randomized block design with three replications in two trials (PT treated plot and PNT untreated plot) was used for the experiment. Results: Results showed that some varieties were resistant to thrips, while others were susceptible. The resistant genotypes were those with a low number of thrips per flower and high pod production. On this basis, KVx780-1 is the best genotype compared with KVx780-6 for varieties currently being popularized. Nafi variety is the best compared with the varieties popularized in 2012 (Nafi, Gourgou, Komcallé and Tiligré). Conclusion: In the case of the varieties that were previously popularized, the results confirmed the susceptibility of KN-1 variety, the tolerance of variety KVx165-14-1 and the resistance of the variety TVx3236.