Maximizing agro-bioeconomic benefits in intercropped systems of radish and lettuce in the semi-arid environment

ABSTRACT Radish and lettuce are two crop vegetables that can be intercropped because they are companion cultures that complement each other. Thus, this study aimed to evaluate agro-bioeconomic returns arising from radish-lettuce intercropping in different equitable amounts of hairy woodrose (Merremia aegyptia) and roostertree (Calotropis procera) biomass at different population densities of lettuce, in the semi-arid environment. The experimental design was in randomized blocks, with treatments arranged in a 4 × 4 factorial scheme with four replicates. The first factor consisted of equitable amounts of M. aegyptia and C. procera biomass at doses of 20, 35, 50, and 65 Mg ha-1 on a dry basis. The second factor comprised four lettuce population densities of 150, 200, 250, and 300 thousand plants ha-1. The lettuce and radish cultivars planted were ‘Tainá’ and ‘Crimson Gigante’, respectively. Expressive agro-bioeconomic returns from this radish-lettuce intercropping were obtained in the land equivalent ratio (LER) of 2.25, a score of the canonical variable Z of 3.00, net income (NI) of 52,270.48 R$ ha-1, respectively, in the biomass amount of 65 Mg ha-1 of the green manures and lettuce population density of 300 thousand plants ha-1. Also, there was a productive efficiency index (PEI) of 0.96 and a competitive ratio (CR) of 2.61 in the biomass amount of green manure of 65 Mg ha-1 and lettuce density of 150 thousand plants ha-1. Using M. aegyptia and C. procera biomass from the Caatinga biome proved to be a viable technology for producers who practice the cultivation of radish and lettuce in intercropping in the semi-arid environment. RESUMO O rabanete e a alface são duas hortaliças que podem ser consorciadas, porque são culturas companheiras que se complementam. Assim, este estudo teve como objetivo avaliar retornos agro-bioeconômicos advindos do consórcio rabanete-alface em diversas quantidades equitativas de biomassa de jitirana (Merremia aegyptia) e flor-de-seda (Calotropis procera) em diferentes densidades populacionais de alface, em ambiente semiárido. O delineamento experimental utilizado foi em blocos ao acaso, com os tratamentos dispostos em esquema fatorial 4 × 4, com quatro repetições. O primeiro fator consistiu em quantidades equitativas de biomassa de M. aegyptia e C. procera nas doses de 20, 35, 50 e 65 Mg ha-1 em base seca. O segundo fator compreendeu quatro densidades populacionais de alface de 150, 200, 250 e 300 mil plantas ha-1. As cultivares de