AGRONOMIC PERFORMANCE OF COWPEA [VIGNAUNGUICULATA(L.) WALP.] VARIETIES AS INFLUENCED BYCOMBINED APPLICATION OF POULTRY MANURE AND MINERAL FERTILIZER IN TWO AGRO-ECOLOGICAL ZONES OF BURKINA FASO

Field experimentwas laid ina split plot design in 2019 and 2020 at rainy seasonsat Farako-Ba in soudanianandKamboinse insoudano-sahelian agro-ecological zones of Burkina Faso. The fertilizer levels (0 kg/ha, 100 kg/ha NPK as control, 60 kg/ha NPK + 1.5 t/ha poultrymanure, 100 kg/ha NPK + 1.5 t/ha poultry manure and 75 kg/ha TSP (P205) + 1.5 t/ha poultry manure) occupied the main plots while the cowpea varieties (KVx745-11P, Komcalle, Tiligre and Neerwaya) were assigned to thesub-plots. The results of the study showed that location as well as fertilizer application rate have significantly affected most of agronomic characters. The average yield recorded in Farako-Ba were 1013.79 kg/ha and 1030.51 kg/ha for 2019 and 2020 while in Kamboinse it was 1166.59 kg/ha and 1165.03 kg/ha, in 2019 and 2020, respectively. The highest grain yield was recorded with combined application of poultry manure with mineral fertilizer at 100 kg/ha NPK + 1.5 t/ha poultry manure.This was followedby 75 kg/ha TSP (P205) + 1.5 t/ha poultry manure.Theresults suggest that combinedapplication of poultry manure and chemical fertilizer can restore soils and lead to high yields in cowpea.