Agro-economic performance of the association of beet with green cowpea in different amounts of hairy woodrose

ABSTRACT Intercropping systems of beet and green cowpea are beginning to be implemented in the northeastern semi-arid region in Brazil. The great challenge is to know if there is agro-economic efficiency in these systems when fertilized with organic matter produced by spontaneous species of the Caatinga biome. Thus, the objective of this research was to evaluate the effect of green manuring using different amounts of hairy woodrose (Merremia aegyptia) in the association of beet with green cowpea under the semi-arid conditions. The experiment was carried out at the Rafael Fernandes Experimental Farm, rural area of Mossoró, RN, Brazil, in the period of September-December 2015, in a randomized complete block design with four treatments and five replicates. The treatments consisted of hairy woodrose amounts incorporated into the soil (10, 25, 40, 55 t ha-1 on a dry basis). The cultivars of beet and green cowpea planted were ‘Early Wonder’ and ‘BRS Itaim’, recommended for the semi-arid conditions of the Brazilian Northeast. The best agro-economic performance for intercropping system of beet and green cowpea was obtained with 55 t ha-1 of hairy woodrose incorporated in the soil. The use of the hairy woodrose species as green manure is agronomically viable in intercropped systems with beet and green cowpea.

摘要 甜菜与绿叶豇豆间作体系目前已开始在巴西东北部半干旱地区推广应用。当前的核心挑战在于明确：当施用卡廷加（Caatinga）生物群系自生植被所产生的有机质肥时，此类间作体系是否具备农业经济效率。为此，本研究旨在评估半干旱环境下，不同施用量的毛鱼黄草（Merremia aegyptia）绿肥对甜菜与绿叶豇豆间作体系的影响。本试验于2015年9月至12月在巴西里约格兰德州莫索罗市郊的拉斐尔·费尔南德斯试验农场开展，采用随机完全区组设计，设置4个处理与5次重复。各处理分别为按干重计10、25、40、55 t·ha⁻¹的毛鱼黄草还田量。供试的甜菜与绿叶豇豆品种分别为适配巴西东北部半干旱环境的‘早熟奇迹’（Early Wonder）与‘BRS伊塔因’（BRS Itaim）。试验结果显示，当毛鱼黄草施用量为55 t·ha⁻¹时，甜菜与绿叶豇豆间作体系可获得最优农业经济表现。综上，将毛鱼黄草用作绿肥，在甜菜与绿叶豇豆间作体系中具备农艺可行性。