Desempenho do cultivo consociado de milho (Zea mays L,) e feijão nhemba (Vigna ungiculata (L) Walp) em diferentes níveis de irrigação e adubação mineral no Posto Administrativo de Sábiè

Abstract

Agriculture is the main source of subsistence and income for the Mozambican population, and is practiced in rainfed and intercropped systems. Intercropping maize and cowpea is a common practice among smallholder farmers. However, this activity has faced low yields due to irregular rainfall and soil degradation, which results in reduced productivity. Given this scenario, the present study aims to evaluate the performance of intercropping maize and cowpea at different levels of irrigation and mineral fertilization. For this purpose, a trial was carried out between December 27, 2023 and May 31, 2024 in the district of Moamba, administrative post of Sábiè, at the Sábiè Agrarian Development Center (CEDAS), using a randomized complete block design in a factorial arrangement, with three factors. The factors were, irrigation: 2 levels (irrigated and rainfed); Fertilization: 2 levels (with and without fertilization) and cultivation system: 3 cultivation systems (sole maize, sole cowpea and maize and cowpea intercropping). Thus, the trial consisted of a 2×2×3 combination, totaling 12 treatments, with 4 replicates, which resulted in a total of 48 plots, each with an individual size of (4 m X 3.2 m). For growth analysis, plant height, leaf area index and accumulated dry matter of the crops were measured. For the maize crop, the yield components evaluated were number of ears per plant; number of grains per ear; average weights of ears, kernels, grains, 100 seeds and grain yield; for the cowpea crop, the number of pods per plant; number of grains per pod; average weights of pods, grains, 100 seeds and grain yield were determined. All growth and yield parameters evaluated were significantly influenced (p<0.05) by water levels. Sole maize with fertilization obtained the highest yield (4.1 tons/ha) in the irrigated level. In cowpea, the highest yield was obtained in the non-irrigated level with and without fertilization (2.7 tons/ha) and did not present statistical difference in cropping systems. Height and leaf area index and aerial dry matter presented strong positive Pearsen correlation with the average crop yield obtained (r = 0.96). Intercropping was not efficient in land use in the rainfed treatments with and without fertilization (LER = 0.79 and 0.87, respectively), but was efficient in land use in the irrigated treatments with and without fertilization (LER = 1.04 and 1.18, respectively). In this situation, intercropping maize and cowpea is recommended under rainfed conditions, as this is where the highest cowpea yield was obtained, whereas under irrigated conditions, sole maize cultivation is recommended