Productivity, Stability and Economic Benefits of Maize-Cowpea Intercrop in the Sudan Savannah Zone in Ghana.

Abstract

A maize-cowpea intercrop two-location experiment was conducted at the experimental fields of the CSIR-SARI at Manga, Binduri District and at the PAS at Garu, Garu District, from July – October 2021 and July – October 2022. The general objective of this study was to enhance a maize-cowpea intercrop productivity in a two-location trial as a climate smart technique to increase crop productivity in the Sudan Savannah Agro-Ecological zone is located in Bawku area in the Upper East Region of Ghana. The study was a 3 x 3 factorial experiment laid out in a Randomized Complete Block Design (RCBD) with four replications. The factors studied were (A) Row arrangements: - [(i)1 row maize altenating with 1 row cowpea (1M:1C), (ii) 2 rows maize altenating with 2 rows cowpea (2M:2C) and (iii) 3 rows maize alternating with 3 rows cowpea (3M:3C)] and (B) Relative times of planting: - [(i)Simultaneous planting of maize and cowpea (SIM), (ii) maize planted 2 weeks before cowpea (M2WBC) and cowpea planted 2 weeks before maize (C2WBM)]. Sole maize and sole cowpea crops were included in the treatments. The intercropping systems largely enhanced both the phenological development and growth performance of the component crops in comparison with sole maize and cowpea. The yield and yield components of maize and cowpea intercrop were significantly greater than the sole crops at Garu and Manga in 2021 and 2022. Planting maize and cowpea simultaneously (SIM) at 2M:2C produced the greatest maize yield of 13.33t/ha, followed by planting maize 2WBC at 2M:2C (8.27t/ha). The greatest cowpea yield was obtained when cowpea was planted 2WBM at 1M:1C (3.79t/ha), followed by planting maize and cowpea simultaneously (SIM) at 1M:1C. Yield stability analysis indicated that 1M:1C + C2WBM and 2M:2C + C2WBM for maize and 2M:2C + M2WBC, 2M:2C + SIM and sole cowpea for cowpea had regression coefficient values that were close to 1, making these systems more stable. Land equivalent ratio for the intercrops ranged from 0.93-2.67 at Garu and 1.23-2.18 at Manga. The intercrop systems were economically profitable with the benefit-cost ratios (BCR) that ranged from 37.77-69.78 compared with BCR for sole crops (11.36-33.08) at Garu and 31.27-60.29 compared with BCR for sole crops (18.65-22.77) at Manga. It is recommended that farmers with priority for more maize yields could adopt planting the two crops simultaneously at 2M:2C row arrangement for maximum yield and high economic benefits; and farmers with priority for more cowpea yields could adopt planting cowpea 2 weeks before maize at 1M:1C to maximize yields and profit.