Effects of MAX NP+ 20-20-20 Foliar Fertilizer Application on the Yield of French Bean in the Semiarid Area of Ethiopia

Abstract

Declining soil fertility poses a significant challenge to increasing sustainable productivity, which, in turn, impacts food security in Ethiopia. In response to this issue, a fertilizer trial was conducted at five sites in the East Showa zone during the 2023/24 dry cropping season under irrigation. The objective of this trial was to evaluate the efficacy of MAX NP+ 20-20-20 foliar fertilizer as a viable alternative to conventional fertilizers for the production of French beans. MAX NP+ is a specialized liquid NPK fertilizer that contains 20N, 20P₂O_5, 20K₂O, and -6MgO in g L^-1. The trial comprised sole MAX NP+ 20-20-20 (2 L ha^-1) and its integration with a full dose of recommended chemical fertilizer (79-142 kg N-P ha^-1), three-quarters dose of RCF (59.3-107.0 kg N-P ha^-1), and half dose of RCF (39.5-71 kg N-P ha^-1) from chemical fertilizers. Full dose of RCF from chemical fertilizers and a negative control with no MAX NP+ 20-20-20 and chemical fertilizer inputs included as controls, resulting in a total of six treatments. The experiment was laid out in a randomized complete block design, replicated three times. The results demonstrated that the new MAX NP+ 20-20-20, combined with 75% of the recommended chemical fertilizer, significantly enhanced the pod yield of French beans. The economic analysis also revealed higher net benefits and marginal rates of return associated with these fertilizer combinations. Given the agronomic and economic advantages, the use of MAX NP+ 20-20-20 foliar application in conjunction with 75% of the recommended fertilizer is recommended for French bean production in the tested locations. Validation across multiple locations and seasons is recommended for broader application.