Agronomic and productivity efficiency of two animal manure sources on intercropped maize-groundnut in the derived savannah

Two animal manure sources (swine and sheep / goat manures) each at 5 Mt·ha⁻¹, were applied in mono- and intercropped maize (Zea mays L.) and groundnut (Arachis hypogea L.). A general control (no manure treatment of the component crops was established) for productivity assessment. The trial, conducted at the Federal College of Agriculture, Ishiagu (04º 30′ N, 06º 45′ E, 150 m above sea level), in the derived savannah plains, Ishiagu, Nigeria in 2012 and 2013 mid-cropping seasons used a randomised complete block design with three replications. It assessed the agronomic performance, cropping system (CS) and plant nutrient (PN) productivity of maize-groundnut in mono-and intercrop as influenced by two animal manure sources. The two-year combined analysis indicated that animal manure sources significantly (P < 0.05) increased growth and yield components of the crop species in the systems. Swine manure application gave the significantly (P < 0.05) highest maize grain yield in both mono- and intercropped strategies in contrast to sheep / goat manure that had the highest grain yield in both cropping strategies in groundnut. The biological and economic productivity indices of the cropping system (CS) and plant nutrient (PN) indicated that the application of sheep / goat manure in the maize / groundnut mixture exhibited greater intercrop advantage whose total CS and PN land equivalent ratios (LERs) were higher by 4.79% and 13.57%, respectively, relative to swine manure application. Therefore, the application of animal manure demands encouragement in maize-groundnut intercrop, especially sheep / goat manure as it enhances crop yield, food security and protein intake of people living in Sub-Saharan Africa practicing different strokes of farming system technology. The results of this study showed that intercropping system exhibited positive growth, yield, biological and economic advantages over monocropping of the component species. The study further indicated that intercropped maize / groundnut that received sheep / goat manure exhibited the highest cropping system and plant nutrient yield advantage and agronomic efficiency compared to swine manure alone under the same environment.