RESUMO O presente trabalho teve como objetivos avaliar o efeito da adubação com esterco bovino em atributos de fertilidade de solos com diferentes teores de argila e, verificar a influência da adubação com esterco bovino na produção de alface americana, e da rúcula e almeirão, cultivados de forma sucessiva a alface. O experimento foi realizado em vasos, em delineamento em blocos ao acaso, com os tratamentos arranjados em esquema fatorial 3x6 com quatro repetições. Os tratamentos foram constituídos por três solos com diferentes teores de argila (166; 362; 565 g kg-1) e seis doses de esterco bovino (0; 10; 20; 40; 80 e 160 t ha-1). Porções de cada solo receberam esterco bovino e calcário, foram transferidas para vasos, umedecidas e incubadas por 30 dias. A seguir, efetuou-se adubação mineral de plantio e cada vaso recebeu uma muda de alface. Após a colheita da alface, para avaliar o efeito residual da adubação orgânica foram realizados dois cultivos sucessivos, um de rúcula e outro de almeirão. A aplicação de até 160 t ha-1 de esterco bovino diminui a acidez e, aumenta os teores de nutrientes, particularmente P, K e Zn em solos com teores de argila de 165 a 565 g kg-1. A adubação com esterco bovino em doses de até 160 t ha-1 aumenta a condutividade elétrica dos solos, e esse acréscimo não prejudica o crescimento e a produção de hortaliças folhosas. A adubação com esterco bovino aumenta a produção de alface, como também a de rúcula e almeirão, cultivados de forma sucessiva. | ABSTRACT The effect of organic fertilization with cattle manure on fertility properties of soils with different clay contents was evaluated; as well as the influence of cattle manure fertilization on the production of lettuce, and on subsequent arugula and common chicory grown in these soils. The experiment with pot plants was arranged in randomized blocks and analyzed in a 3x6 factorial design with four replications. The treatments consisted of three soil types with different clay contents (166; 362; 565 g kg-1) and six cattle manure rates (0; 10; 20; 40; 80, and 160 t ha-1). Batches of each soil were manured, limed, filled in pots, moistened, and incubated for 30 days. Then, mineral base fertilization was applied and one lettuce seedling per each pot was grown. After lettuce harvest, the residual effect of organic fertilization was assessed in two subsequent crops, first arugula and then common chicory. The application of up to 160 t ha-1 cattle manure reduces soil acidity and increases nutrient contents, particularly of P, K and Zn, in soils with 165 to 565 g kg-1 clay content. Fertilization with cattle manure at rates of up to 160 t ha-1 increases electrical conductivity of soils, without affecting growth and yield of the leafy vegetables. Cattle manuring increases the yield of lettuce, as well as of arugula and common chicory grown afterwards.

ABSTRACT Vegetable intercropping systems use complementarity between species to increase agricultural profitability. This study evaluated the effects of intercropping chicory and arugula species with collard greens on crop yield and land use efficiency (LUE). Six treatments, consisting of species planted as monocultures or intercropped in various combinations, were evaluated in a randomized block design with four replicates. The cultivars ‘Top Bunch’ (collard greens), ‘Pão de Açúcar’ (chicory) and ‘Folha Larga’ (arugula) were used. The yield of collard greens in monoculture did not differ from those obtained when they were intercropped with chicory, arugula, or both species, whereas chicory and arugula yields were higher in monoculture. However, even with yield losses for chicory and arugula in intercropping, LUE indices were greater than 1.0 in all intercropping systems, indicating their viability. The highest LUE index (2.41) was obtained in the chicory-arugula-collard green intercropping system.