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In order to know how some management indicators of silvopastoral systems and their plant health contribute to the duration of the main forage species that form their associations, eight silvopastoral systems were sampled (six in Matanzas province and two in Mayabeque province). The botanical composition of grasslands was measured, as well as the amount of weeds, the associated entomofauna and its functional composition. Results indicated that, having a proper management in paddocks of silvopastoral systems, in paddocks 1, 2, 4, 6 and that of double purpose (bull fattening-seed production), there was an increase of the percentage of meadow species in the botanical composition and the density of leucaena trees per hectare was maintained. A similar performance was obtained with the presence of phytophagous and beneficial insects, mainly in these last, which prevented massive outbreaks of pests during the evaluated period. In the paddocks with SSP-4, 5, 6 and 7, where the percentage of natural grasses increased, there was also an increase of the number of weeds, which is an indicator of bad management in animal husbandry, although in some cases they can be used as shelter and/or food (pollen or nectar) for predators and parasitoids, as it happened in the SSP-4 and 6. It can be concluded that management indicators (necessary rest time of the grass, animal stay and proning labors), as well as the conservation of natural enemies in the favorable environment created for them, allowed to maintain the biological balance (without massive outbreaks of pests) in the areas during the evaluated period. They also contributed to the persistence in time of the permanent forage plant resources that compose these systems (in their majority), and to their economic and environmental sustainability. [ABSTRACT FROM AUTHOR]

El objetivo de este trabajo fue caracterizar cultural y morfológicamente diez aislamientos de Fusarium, obtenidos de semillas de L. leucocephala cv. Perú almacenadas, con vistas a su clasificación taxonómica. Sus cultivos puros se conservaron en tubos Eppendorf con medio Agar Papa y Dextrosa (APD), en cámara fría a 10°C. La siembra de cada aislamiento se realizó en tres placas Petri, esterilizadas, de 9 cm de diámetro; estas contenían, separadamente, los medios APD y Agar Papa Sacarosa (APS), que constituyeron las réplicas; se colocó en su centro un disco micelial de 7 mm de diámetro, procedente de cultivos con 10-15 días de edad, sembrados también en dichos medios. Posteriormente, las placas se sellaron con papel parafinado y se incubaron durante diez días a 25°C, con alternancia de 8 h de luz/16 h de oscuridad, o a oscuridad constante. Las variables culturales medidas fueron: el color de la colonia en el anverso y el reverso, la textura y el crecimiento lineal y aéreo; y como morfológicas se evaluaron: el tamaño, la forma y el color de las estructuras vegetativas y reproductivas que aparecieron en los cultivos. Se utilizó un diseño completamente aleatorizado y los datos se procesaron estadísticamente a través de un análisis descriptivo. Para la identificación de los hongos se utilizaron diferentes claves taxonómicas. Los aislamientos 10, 18 y 29 se correspondieron con las características descritas en la literatura científica para la especie Fusarium oxysporum Schlecht; el 17, el 28 y el 30, con Fusarium sambucinum Fuckel; el 27, con Fusarium semitectum Berk & Rav.; el 25 y el 26, con Fusarium incarnatum (Rob) Sacc, y el 31, con Fusarium chlamydosporum Wollenw & Reinking, lo que permitió la identificación de cinco especies de Fusarium asociadas a las simientes almacenadas. [ABSTRACT FROM AUTHOR]

The objective of this paper is to analyze the evolution of the most important scientific results related to the management of grazing systems for dairy production in Cuba, during the last 40 years of research. The compilation made allowed to generate a group of principles that rule the management with improved grasses, twining legumes and trees for browsing. The challenges in the conception of milk production systems in Cuba, which constitute the new paradigm: food and energy production on improved grasses in association with fodder, energy, timber and other trees, that cover 80 % of the animals' requirements, were analyzed. [ABSTRACT FROM AUTHOR]

The objective of this paper is to analyze the evolution of the most important scientific results related to the management of grazing systems for dairy production in Cuba, during the last 40 years of research. The compilation made allowed to generate a group of principles that rule the management with improved grasses, twining legumes and trees for browsing. The challenges in the conception of milk production systems in Cuba, which constitute the new paradigm: food and energy production on improved grasses in association with fodder, energy, timber and other trees, that cover 80 % of the animals' requirements, were analyzed. [ABSTRACT FROM AUTHOR]

The objective of this work was to characterize cultural and morphologically ten Fusarium isolates, obtained from stored Leucaena leucocephala cv. Peru seeds, aiming at their taxonomic classification. Their pure cultures were preserved in Eppendorf tubes with Potato Dextrose Agar (PDA) medium, in cold chamber at 10ºC. Each isolate was planted in three sterilized Petri dishes, of 9 cm diameter; they contained, separately, the PDA and Potato Sucrose Agar (PSA) media, which constituted the replicates; at their center a mycelial disk was placed, of 7 mm diameter, from 10-15-day-old cultures, also planted in such media. Afterwards, the dishes were sealed with wax paper and incubated for ten days at 25ºC, alternating 8 h of light/16 h of darkness, or in constant darkness. The measured cultural variables were: colony color on the obverse and reverse, texture and lineal and aerial growth; and the morphological variables were: size, shape and color of the vegetative and reproductive structures which appeared in the cultures. A completely randomized design was used, and the data were statistically processed through a descriptive analysis. For the fungi identification different taxonomic keys were used. Isolates 10, 18 and 29 were in correspondence with the characteristics described in scientific literature for the species Fusarium oxysporum Schlecht; 17, 28 and 30, to Fusarium sambucinum Fuckel; 27, to Fusarium semitectum Berk & Rav.; 25 and 26, to Fusarium incarnatum (Rob) Sacc, and 31, to Fusarium chlamydosporum Wollenw & Reinking, which allowed the identification of five Fusarium species associated to the stored seeds. [ABSTRACT FROM AUTHOR]

A mycological diagnosis was carried out on seeds from Leucaena leucocephala cv. Peru which had been stored for 18 months under environmental conditions, with the objective of identifying the main fungi associated to them, and to determine the ones that had not been previously recorded. For that, Blotter Test was used according to the recommendations of ISTA (1999) for the pathological analysis of the seeds from tropical trees. The isolations of the fungi obtained were characterized from the morphological, cultural and pathogenic point of view. The most important finding was the detection and identification, for the first time in Cuba, of the legume tree under study; characteristics which coincided with the description in the different taxonomic keys consulted. Besides, the pathogenic character of such fungal agent could be detected as it caused a 20% rot to seeds that had not been germinated. [ABSTRACT FROM AUTHOR]