Alisson Vinicius de Araujo

Cobertura morta e adubação orgânica na produção de alface e supressão de plantas daninhas

Objetivou-se, neste trabalho, avaliar os efeitos da cobertura do solo e da adubacao orgânica sobre a temperatura e a umidade do solo, a incidencia de plantas daninhas e a produtividade da alface. O delineamento experimental utilizado foi de blocos casualizados, em esquema fatorial (3 x 3), em que o primeiro fator corresponde aos tipos de cobertura morta (capim tifton, capim napier e ausencia de cobertura) e, o segundo, aos adubos (esterco bovino, esterco de galinhas e ausencia de adubacao). Analisaram-se as variaveis temperatura e umidade do solo, o numero de folhas produzidas pela alface, as massas de materia fresca e seca da parte aerea, das plantas de alface e daninhas, e o levantamento fitossociologico das plantas infestantes. As plantas adubadas com esterco de galinhas apresentaram massas de materia fresca e seca superiores as das plantas nao adubadas. A cobertura morta com capim tifton proporcionou aumento da massa de materia seca das plantas de alface, o que pode estar relacionado com a menor temperatura dos canteiros que receberam esse material como cobertura. Commelina benghalensis foi a planta infestante mais importante no cultivo orgânico de alface. A aplicacao de adubos orgânicos e a cobertura morta com capins nao foram capazes de suprimir plantas daninhas e manter a umidade do solo, em areas de cultivo de alface.

Time of harvest and storability of Crotalaria juncea L. seeds

Although used as green manure, one of the challenges the cultivation of Crotalaria juncea is the low availability of quality seeds in the market. The harvest at the right time contributes to the achievement of better quality seeds. The objectives of this study were to evaluate the storability and characterize the physical and physiological changes of the seeds harvested at different times. The statistical design was completely randomized with three replications. Treatments consisted of four harvest seasons and two storage periods (0 to 8 months). The samples were collected when the plants reached 40, 60, 80 and 100% of dried pods. The following characteristics were evaluated: time for drying, moisture content, dry matter accumulation, physical purity, yield, uniformity testing, seed coat coloring, germination, germination first count test, percentage of hard seeds, speed index and percentage of seedling emergence. Data from ripening stages were submitted to regression analysis. The effect of storage within each time it was analyzed by the joint analysis of variance of the results and the Tukey test (p≤0.05). The determination of the sampling point based on the percentage of dried beans is efficiently. The physiological maturity of the seeds is achieved when the plants have about 86.1% of dry beans, with the Crotalaria juncea seeds harvesting is performed at the point where the plants have between 80 and 100% of dried pods. The storage for eight months reduces dormancy up to 75.4%.