ABSTRACT In this study, the objective was to determine the post-harvest indexes of arugula leaves and beet roots in intercropping under a biomass mixture of different green manures at diverse arugula population densities in two cropping seasons in a semi-arid environment. The experimental design was a randomised complete block design, with treatments arranged in a 4 × 4 factorial scheme with four replications. Treatments consisted of the combination of equitable amounts of Merremia aegyptia and Calotropis procera biomass (20, 35, 50 and 65 t ha-1 on a dry basis) and arugula population densities (400,000, 600,000, 800,000 and 1,000,000 plants ha-1). The characteristics evaluated in the arugula culture were titratable acidity, pH, and soluble solid and total soluble sugar content. In the beet crop, the same characteristics were evaluated in arugula, in addition to the betalain concentration and the internal colour parameters of the tuberose roots. Arugula showed the best post-harvest indexes when fertilised with green manure biomass amounts of 20, 20 and 65 t ha-1 at a population density of 1,000,000 plants ha-1, while beet showed the best indices with green manure amounts of 65, 41, 36 and 40 t ha-1 with an arugula density of 1,000,000 plants ha-1. The best colour parameters of beet roots were obtained with green manure amounts of 30 and 32 t ha-1 at an arugula density of 400,000 plants ha-1.

RESUMO A adubação verde com espécies espontâneas da Caatinga tem se mostrado uma alternativa viável para fornecer nutrientes às hortaliças e, assim, aumentar sua produtividade. O objetivo deste estudo foi avaliar e estimar as máximas eficiências físicas e econômicas das características produtivas do coentro em função de quantidades equitativas de biomassa de jitirana [Merremia aegyptia (L.) Urban] e flor-de-seda [Calotropis procera (Aiton) W. T.] em diferentes safras. O delineamento experimental foi em blocos casualizados, com cinco tratamentos e cinco repetições. Os tratamentos foram constituídos pelas quantidades de adubos verdes (16, 29, 42, 55 e 68 t ha-1 em base seca). Em cada experimento foi utilizado um tratamento sem fertilização (controle). A máxima eficiência agronômica (rendimento de massa verde do coentro) foi possível com a incorporação das quantidades equitativas de 49,56 t ha-1 de biomassa de M. aegyptia e C. procera, respectivamente. A máxima eficiência econômica de produção (avaliada em termos de renda líquida e taxa de retorno) dessa hortaliça folhosa foi alcançada com a adição ao solo de 42,68 e 41,64 t ha-1 de biomassa desses adubos verdes, respectivamente. A renda líquida e a taxa de retorno otimizadas para essas quantidades de adubos verdes foram de 30.243,92 R$ ha-1 e 2,79 reais para cada real investido na produção dessa hortaliça. A utilização da biomassa de Merremia aegyptia e Calotropis procera do bioma Caatinga mostrou-se uma tecnologia viável para produtores que praticam o cultivo de coentro em monocultivo em ambiente semiárido.

ABSTRACT Green manuring with spontaneous species from the Caatinga has emerged as a viable alternative to supply vegetables with nutrients and thus increase their productivity. This study aimed to evaluate and estimate the maximum physical and economic efficiencies of coriander productive characteristics as a function of equitable biomass amounts of hairy woodrose [Merremia aegyptia (L.) Urban] and roostertree [Calotropis procera (Aiton) W. T.] in different cropping seasons. The experimental design was a randomized complete block with five treatments and five replicates. The treatments consisted of green manure amounts (16, 29, 42, 55, and 68 t ha-1 on a dry basis). A treatment without fertilization (control) was used in each experiment. The maximum agronomic efficiency (coriander green mass yield) was possible with the incorporation of equitable amounts of 49.56 t ha-1 of M. aegyptia and C. procera biomass, respectively. The maximum economic efficiency of production (evaluated in terms of net income and rate of return) of this leafy vegetable was achieved with the addition to the soil of 42.68 and 41.64 t ha-1 of biomass of these green manures, respectively. The net income and the rate of return optimized for these amounts of green manures were 30,243.92 R$ ha-1 and 2.79 reais for each real invested in the production of this leafy vegetable. The use of biomass from Merremia aegyptia and Calotropis procera from the Caatinga biome proved to be a viable technology for producers who practice the cultivation of coriander when monocropping in a semiarid environment.

RESUMO Diante da falta de informações sobre o uso de plantas espontâneas do bioma Caatinga como adubos verdes para produção de grãos verdes, esse trabalho teve como objetivo otimizar agronômica e economicamente a produção de feijão-caupi para grãos verdes e de seus componentes quando adubado com quantidades equitativas de biomassa das espécies jitirana (Merremia aegyptia L.) e flor-de-seda (Calotropis procera Ait.) em duas estações de cultivos em ambiente semiárido. O delineamento experimental utilizado foi em blocos completos casualizados, com cinco tratamentos e cinco repetições. Os tratamentos consistiram de quantidades equitativas de biomassa de jitirana (Merremia aegyptia) e de flor-de-seda (Calotropis procera) nas doses de 16, 29, 42, 55 e 68 t ha-1 em base seca. Em cada experimento foi plantado um tratamento adicional com feijão-caupi sem adubo (testemunha absoluta) e outro adubado com fertilizante mineral para efeito de comparação com o tratamento de máxima eficiência fisica ou econômica. As máximas eficiências físicas (agronômicas) otimizadas da produção de vagens e grãos verdes de feijão-caupi foram alcançadas na produtividade de vagens verdes de 3,90 t ha-1 e na produtividade de grãos verdes de 4,06 t ha-1, com a incorporação ao solo de 45,07 e 50,48 t ha-1 de biomassa dos adubos verdes, respectivamente. A máxima eficiência econômica da produção de grãos verdes do feijão-caupi foi alcançada na renda líquida de 5.826,12 R$ ha-1 e na taxa de retorno 1,29 reais por cada real investido com aplicação ao solo de 38,74 e 37,85 t ha-1 de biomassa dos adubos verdes testados.

ABSTRACT Given the lack of information on the use of spontaneous plants from the Caatinga biome as green manure to produce green grains, the present work aimed to agronomically and economically optimize cowpea production for green grains and their components when fertilized with equitable biomass amounts of hairy woodrose (Merremia aegyptia L.) and roostertree (Calotropis procera Ait.) in two cropping seasons in a semi-arid environment. The experiment used a randomized complete block design, with five treatments and five replicates. The treatments consisted of equitable amounts of dry M. aegyptia and C. procera biomass of 16, 29, 42, 55 and 68 t ha-1. In each experiment, an additional treatment was planted with cowpea without fertilizer (absolute control), and another was fertilized with mineral fertilizer for the purpose of comparison with the treatment of maximum physical or economic efficiency. The maximum optimized physical (agronomic) efficiencies of cowpea green pods and grain production were reached in the productivity of green pods at 3.90 t ha-1 and green grains at 4.06 t ha-1, with incorporation into the soil of 45.07 and 50.48 t ha-1 of green manure, respectively. The maximum economic efficiency of cowpea green grain production was reached at a net income of R$5826.12 ha-1 and at a rate of return of 1.29 reals for each real invested with application to the soil of 38.74 and 37.85 t ha-1 of the tested green manure biomass.

Abstract The objective of this study was to evaluate and estimate the post-harvest indices and color parameters of beet roots in intercropping with lettuce under green manuring with different equitable amounts of M. aegyptia and C. procera biomass (20, 35, 50 and 65 t ha-1 on a dry basis) in diverse population densities of lettuce (150, 200, 250 and 300 thousand plants ha-1), in two cropping seasons in semi-arid environment. The lettuce crop presented the best post-harvest indexes when submitted to fertilization with an amount of M. aegyptia and C. procera biomass of 20 t ha-1 in lettuce population densities between 203 and 300 thousand plants per hectare. The beet crop reached the best indices when it was manured with amounts of the green manures between 20 and 55 t ha-1 and between lettuce population densities of 150 and 300 thousand plants per hectare. The color parameters of purple/red beet roots (well appreciated by the consumers) were obtained in the amounts of green manures between 25 and 65 t ha-1 and between lettuce population densities of 280 and 300 thousand plants per hectare.