EFFICIENCES AGRONOMIQUE ET ECONOMIQUE DES DOSES D'ENGRAIS NPK UTILISEES DANS LA PRODUCTION DE MAIS (Zea mays L.) A KALEHE ET DANS LA PLAINE DE LA RUZIZI (original) (raw)

ABSTRACT Assessing agronomic and economic efficiencies of NPK rates on maize (Zea mays L.) production in Kalehe and Ruzizi Plain. KAMOLE MULASHE Rodrigue, MULUMUNA WA LOLA Janvier, WALANGULULU MASAMBA Jean rodrigue.mulashe@gmail.com In the South-Kivu Province, maize is the most cultivated cereal, although yields are low due mainly to low soil fertility and underuse of appropriated agricultural inputs such as fertilizers because of the low financial capacity. However, those who use fertilizers apply rates that, sometimes, are not fitted with the local pedo-climatic and socio-economical context, implying often wastage and lack of fertilizer use efficiency. Thus, to assess both agronomic and economic efficiencies of six NPK fertilizer rates [T0 (NPK 0-0-0), T1 (NPK 15-15-10 + 10t FYM), T2 (NPK 45-15-10 + 10t FYM), T3 (NPK 90-30-15 + 10t FYM), T4 (NPK 120-50-40 + 10t FYM) and T5 (NPK 0-0-0 + 10t FYM)]; a multi locations trial was installed in 3 locations in Kalehe (Kalehe-centre, Kasheke and Muhongoza) and in Ruzizi plain (Kiliba, Biriba and Muhongoza). Results have shown that: NPK 15-15-10 + 10t FYM gave the highest yield in Biriba, in Kalehe-centre and Muhongoza; NPK 45-15-10 + 10t FYM and NPK 90-30-15 + 10t FYM rates gave the highest yield respectively in Runingu and Kiliba while application of 10tons of farm-yard manure gave the best yield in Kasheke. The highest Agronomic efficiency was obtained by NPK 15-15-10 + 10t FYM in all sites except in Runingu where NPK 45-15-10 + 10t FYM gave the highest value of Agronomic efficiency. EA/EAmax ratio globally followed a downward trend as the fertilizer rates increased, suggesting losses of nutrients. On the economic point of view, NPK 15-15-10 + 10t FYM brought the most interesting income and the highest benefit cost ratio in Biriba, Kalehe-centre and Muhongoza, and so the highest economic efficiency in these 3 sites, and also in Kasheke and Kiliba (respectively BCR of 15,3 ; 20,9 ; 4 ; 16,17 ; and 12,1 clearly superior than 2 which is the profitability critical level according to the FAO criterion). In Runingu, NPK 45-15-10 + 10t FYM was the most economically interesting treatment, with an economic efficiency value of 6,2 also superior than 2, therefore economically efficient. Key-words: Agronomic efficiency, NPK rates, maize, Kalehe, Ruzizi plain Contacts: (+243) 971007990, 850764586, 819411936 Mail: rodrigue.mulashe@gmail.com