Réponse agro-physiologique du niébé à l’intégration innovante de fertilisants organiques et minéraux dans la région de Zinder au Niger

Abstract

Organo-mineral fertilization is an effective approach to improving soil productivity, but its adoption remains limited among small-scale farmers. This study, conducted in the commune of Alberkaram (Kassama site), aimed to evaluate the effects of combining different soil fertility management techniques on cowpea cultivation. The experiment was carried out using a randomized complete block design with three replications and five treatments. Among the growth parameters measured, only stem collar diameter showed no significant difference between treatments (P = 0.060). Plants receiving the NPK + compost (digestate) combination produced more branches (P = 0.024) and nearly twice as many leaves as the control (25.33 ± 0.33). Plants treated with DAP reached 50% flowering at 26 days after sowing compared to 30 days for the control. The digestate treatment resulted in an average of 21.67 ± 0.88 pods per plant, higher than that of the control. The combination of digestate + NPK achieved the highest grain yield (629.11 ± 49.05 kg/ha). These results suggest that digestate, whether used alone or in combination with mineral fertilizer, can significantly enhance soil fertility and increase cowpea yield.