Global Maize in Africa; Wote, Kenya

The study was initiated in Wote, Eastern Kenya in 2013 as part of the Global Maize network of trials to identify site-specific nutrient management practices for sustainable intensification of maize production. The overall objective is to evaluate opportunities for Agroecological Intensification (AEI) as a means to improve maize yields at a faster rate than farmer practice, while minimizing adverse environmental effects. Makueni has semi-arid climate (avg. annual rainfall = 600 mm) and the interaction of water and nutrients has a strong influence on maize productivity. The experimental treatments included: 1) current fertilizer recommendation (60 kg/ha N + 20 kg/ha P); 2) AEI (60 kg/ha N + 20 kg/ha P + 18 kg/ha + 8 kg/ha S + 18 kg/ha Ca + 7 kg/ha Mg + 3 kg/ha Zn + 3 kg/ha B; and 3) 50% AEI consisting of half the fertilizer rate of the AEI treatment. The 50% AEI treatment was included as an option relevant for smallholder farmers who currently use very low rates of fertilizer. The trial has been implanted for three consecutive maize production seasons.

Trial results for the 2015 seasons showed highest yields of 3.4 t/ha for the AEI treatment, followed by the N+P treatment (2.6 t/ha) and the 50% AEI treatment (2.2 t/ha). The results were consistent with results for the previous seasons, which showed improved yields with the application of K, S, Ca, Mg, Zn, and B over the current recommendation. In 2016, detailed economic analysis will be conducted to evaluate the economic benefits of the AEI treatment.