PRODUCTIVE VIABILITY AND PROFITABILITY OF CARROT-COWPEA INTERCROPPING USING DIFFERENT AMOUNTS OF Calotropis procera

ABSTRACT Intercropping system and the use of green manure with spontaneous species has been an alternative farming method applied to the productive sector of vegetables in the northeastern semi-arid region. The objective of this work was to determine which amount of Calotropis procera must be incorporated into the soil to provide the highest productive performance of the component crops and increase the profitability of the carrot and cowpea intercropping. The experimental design used was randomized complete blocks with five replicates. The treatments consisted of four amounts of C. procera incorporated into the soil: 10, 25, 40 and 55 t ha-1 on a dry basis. The characteristics evaluated in this intercropping system were: commercial productivity of carrot roots, yield of cowpea green grains, land equivalent ratios for component crops and for the intercropped system, score of the canonical variable of the association, and the economic indicators of gross income, net income, rate of return, and net profit margin. The maximum agronomic efficiency of the carrot x cowpea intercropping was reached at the land equivalent ratio of 1.12, using 43.39 t ha-1 of C. procera biomass incorporated in the soil, while the maximum economic efficiency of the carrot and cowpea crops association was obtained at the net income of R$ 17,856.43 ha-1, in the amount of 40.60 t ha-1 of C. procera biomass added to the soil.

摘要 间作体系结合野生自发物种绿肥的应用，是巴西东北部半干旱地区蔬菜生产产业的替代性耕作模式。本研究旨在明确适宜的牛角瓜（Calotropis procera）土壤还田量，以实现间作伴生作物的最优生产表现，并提升胡萝卜与豇豆间作体系的种植收益。本试验采用完全随机区组设计，设置5次生物学重复。试验共设置4个干基牛角瓜还田量梯度：10、25、40及55 t ha⁻¹。本间作体系的测定指标包括：胡萝卜块根的商品产量、豇豆鲜籽粒产量、伴生作物及间作系统的土地当量比（Land Equivalent Ratio）、组合同化典范变量得分，以及总收入、净收入、投资收益率与净利润率等经济指标。当土壤施加43.39 t ha⁻¹干基牛角瓜生物量时，胡萝卜-豇豆间作系统的农艺效率达到峰值，此时土地当量比为1.12；而当还田量为40.60 t ha⁻¹时，该间作组合的经济效率最优，净收入可达17856.43巴西雷亚尔每公顷（R$ 17,856.43 ha⁻¹）。