BIOMASS USE OF MERREMIA AEGYPTIA AND CALOTROPIS PROCERA IN CORIANDER CULTIVATION IN SEMIARID ENVIRONMENT

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 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 bio