Productivity of coffee and legumes intercropped under different sun exposure face

Abstract

In mountainous regions, the amount of time that the land is exposed to the sun is one of the factors that influence the productive potential of legumes. The aim of our study was to evaluate, for two different terrain aspects under sun exposure faces, the production of green and dry matter, as well as the nutrient accumulation in the aerial part of legumes and the coffee productivity. The northwest-facing terrain is at 950 m altitude, the average annual temperature is 18.0 °C, the average rainfall is 1320 mm and the average daily solar exposure is 9.1 h. The south-facing terrain is at 690 m altitude, the average annual temperature is 14.0 °C, the average rainfall is 1277 mm and the average daily solar exposure is 6.8 h.The main soil of both terrains are a clayey dystrophic Red-Yellow Oxisol. The experimental design was inrandomized blocks with a 2 x 8 factorial scheme (two different terrain aspects and 8 types of green manure), and four replications were performed.On the northwest-facing terrain, D. lablab, C. spectabilis, and S. deeringianum had the highest amount of dry matter (3.31, 2.98, and 2.85 Mg ha-1, respectively) and nitrogen accumulation (111.54, 91.83, and 91.51 kg ha-1, respectively).The most promising legumes on the south-facing terrain (lower altitude, lower temperature, and lower incidence of light) for dry matter productions were C. spectabilis (3.45 Mg ha-1) and S. deeringianum (3.30 Mg ha-1). C. spectabilis obtained 106.03, 10.36, and 50.42 kg ha-1 of N, P, and K, respectively; while S. deeringianum accumulated 89.98, 8.10, and 52.54 kg ha-1 of N, P, and K, respectively. The use of C. cajan, C. spectabilis, and S.deeringianum resulted in greater coffee productivity on the south-facing terrain than on the northwest-facing terrain.