Abstract This research evaluated the effects of long-term (30 years) winter cover crops under conventional farming system and no-tillage system on edaphic fauna in a Rhodic Hapludox soil, from Paraná State, Brazil. We used three winter cover crops (black oat, hairy vetch and fallow), and as a reference a fragment of natural forest. Soil monoliths were collected at two times, one during the flowering of maize (April 2013) and the other during the flowering of soybean (January 2014). The extraction of the monoliths was carried out in three layers in the soil profile (0-10, 10-20 and 20-30 cm). Seventeen taxonomic groups were sampled. The density of the edaphic fauna is inversely related to soil depth. The winter crops associated with the no-tillage system in long-term resulted in fauna densities similar to the natural environment, with a higher density (density increase of 2.2x) at a depth of 10-20 cm in areas with black oat. At 0-10 cm depth, black oat and vetch under no-tillage systems resulted in an increase of 62% and 69% (April 2013) and 46 and 44% (January 2014), respectively, in the density of soil fauna, when compared to the same winter crops in conventional farming system.

ABSTRACT The research was carried out in “Finca La Loma” agroecosystem, Limonar de Monte Rous community, Guantanamo province, Cuba and had the objective of characterizing the integral functioning of a pre-mountain agroecosystem, for its prospective orientation towards sustainability, based on its agrobiodiversity. The initial diagnosis showed that the agroecosystem possessed acceptable socioeconomic and environmental conditions, revealed in the quality of life of the actors and the abundant agrobiodiversity. The analysis by subsystem, showed the existence of 249 species of 79 families; of them 41 forest species, being Hura crepitans L., the one with the highest carbon retention and Poeppigia procera Presl., the one with the highest frequency. 28 new species were introduced to meet food needs. The value of the Agrobiodiversity Index (IDA) went from 0,67 to 0,77 in three years. The Human Food Index was based on 56 species. The contributions to the sustainability of the agroecosystem showed positive effects for the qualitative and quantitative indicators. Problems related to the lack of: attachment to “the land” among the young, training, afforestation and areas to be developed were detected; limiting to the prospective development of the agroecosystem

RESUMEN La investigación se realizó en el agroecosistema “Finca La Loma”, comunidad de Limonar de Monte Rous provincia Guantánamo, Cuba y tuvo como objetivo caracterizar el funcionamiento integral de un agroecosistema premontañoso, para su orientación prospectiva hacia la sostenibilidad, basado en su agrobiodiversidad. El diagnóstico inicial mostró que el agroecosistema poseía condiciones socioeconómicas y medioambientales aceptables, reveladas en la calidad de vida de los actores y la abundante agrobiodiversidad. El análisis por subsistema, mostró la existencia de 249 especies de 79 familias; de ellas 41 especies forestales, siendo Hura crepitans L., la de mayor retención de carbono y Poeppigia procera Presl., la de mayor frecuencia. Se introdujeron 28 nuevas especies, para cumplimentar necesidades alimenticias. El valor del Índice de Agrobiodiversidad (IDA) pasó de 0,67 a 0,77 en tres años. El Índice Alimentario Humano se sustentó en 56 especies. Los aportes a la sostenibilidad del agroecosistema mostraron efectos positivos para los indicadores cualitativos y cuantitativos. Se detectaron problemas vinculados a la falta de apego a “la tierra” entre los jóvenes, capacitación, forestación y rubros por desarrollar; limitantes para el desarrollo prospectivo del agroecosistema

The study was developed in order to determine the effect of aqueous extracts of Helianthus annuus Lin on Solanum lycopersicum Lin growth. Roots and leaves samples of sunflower plants were collected from a policulture system located in a mountainous agroecosystem and their effects. These effects were evaluated on certified tomato seeds about germination, radicle and hypocotyl length. Nine treatments with four replicates were established in Petri plates. The extracts of sunflower from roots, and from leaves, at 15, 30 and 45 and at 75 and 90 days of development, respectively, inhibited tomato seed germination. Sunflower root extracts at 75 and 90 days of development stimulated tomato radical and hypocotyl growth. These results showed that sunflower plant produces chemical substances inhibiting tomato growth specifically the radicle and the hypocotyl in the earlier 45 days of growth after germination, and it is not recommended the association of these two crops simultaneously

Con el objetivo de determinar el efecto de extractos acuosos de Helianthus annuus Lin. sobre el crecimiento de Solanum lycopersicum Lin, se tomaron muestras de raíz y hojas de plantas recolectadas de un sistema de policultivo ubicado en un agroecosistema montañoso. Los extractos acuosos de girasol se obtuvieron a partir de raíz y hojas de plantas recolectadas durante dos años. Se evaluaron los efectos de estos extractos sobre la germinación, longitud de la radícula y del hipocótilo de semillas de tomate certificadas, para ello se ejecutaron nueve tratamientos con cuatro repeticiones dispuestos en placas Petri. Los extractos de raíz de girasol a los 15, 30 y 45 días y de hojas a los 75 y 90 días de desarrollo inhibieron la germinación de las semillas de tomate y el crecimiento de la radícula y el hipocótilo. Los extractos de raíz de girasol con 75 y 90 días, estimularon el crecimiento de la radícula y del hipocótilo del tomate. Estos resultados demuestran que el girasol produce sustancias químicas que inhiben el crecimiento del tomate y no se recomienda asociar estos dos cultivos de forma simultánea