1,448 research outputs found
Modelo de la dinámica poblacional de Anoda cristata en un cultivo de soja resistente a glifosato bajo diferentes sistemas de manejo
Se desarrolló un modelo de simulación de la dinámica del banco de semillas de Anoda cristata (L.) Schlecht en un cultivo de soja. El modelo considera distintas estrategias de manejo: ausencia de control, control con la dosis recomendada y con la mitad de dicha dosis y dos espaciamientos entre filas del cultivo de soja (35 y 70 cm). El modelo fue evaluado usando datos de experiencias previas realizadas durante 4 años consecutivos. El modelo reprodujo ajustadamente la dinámica del banco de semillas. El banco de semillas decreció más cuando no se produjeron semillas; en ausencia de control, alcanzó una densidad de equilibrio. Cuando se produjeron semillas todos los años, el modelo fue más sensible a cambios en la tasa de predación pero cuando no se produjeron semillas, la mortalidad de éstas fue el proceso más importante. La simulación muestra que puede ocurrir erradicación a largo plazo con el uso continuo de glifosato a la dosis recomendada, o con la combinación de soja sembrada a 35 cm entre filas y la mitad de la dosis recomendada.A computer simulation model was developed to describe Anoda cristata (L.) Schlecht seedbank dynamics in soybeans. The model considers different weed management strategies: absence of control, control with the recommended rate and with glyphosate at half the recommended rate, and two soybean row spacings (35 and 70 cm). The model was evaluated using data from previous experiments obtained for four consecutive years. The model accurately reproduced the seedbank dynamics. The seedbank decreased more in weed management strategies without seed production. In absence of control, the seedbank reached an equilibrium density. When seeds were produced every year, the model output was more sensitive to changes in the rate of predation; but without seed production, seed mortality was the most important process. Simulation demonstrated that long-term eradication may occur with continuous use of glyphosate at the recommended rate or with the combination of soybean at 35 cm between rows and glyphosate at half the recommended rate.Fil: Puricelli, E.. Universidad Nacional de Rosario; ArgentinaFil: Vitta, Javier Ignacio. Universidad Nacional de Rosario; ArgentinaFil: Sabbatini, Mario Ricardo. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - BahÃa Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Orioli, Gustavo Adolfo. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - BahÃa Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentin
Saccharomyces cerevisiae-Based Probiotics as Novel Antimicrobial Agents to Prevent and Treat Vaginal Infections
Vaginal infections affect 70% of women during their lifetimes and account for millions of annual doctors' visits. These infections are predominantly represented by vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV). Although standard antimicrobial agents remain the major strategy for the prevention and treatment of vaginal infections, both VVC and BV are difficult to treat due to high rates of resistance and recurrence, high probability of complications, and negative effects on the vaginal microbiota. This review focuses on a new approach of yeast-based probiotics for the prevention and/or treatment of these common vaginal infections
Diachronic analysis of farmers' strategies within a protected area of central Italy
The farm can be considered as the decision unit in the agricultural
land management, therefore it is the most suitable scale to analyse the
farmers’ strategies of production. In this paper we describe the results
of a comparison between two enquiries carried out in 1992-93 and
2009-10 on more than 30 farms, corresponding to about 1500 ha of
utilised agricultural area (UAA), within the boundaries of the San
Rossore, Migliarino, Massaciuccoli Regional Park (central-western
Italy). We calculate a set of agri-environmental indicators both at territory
and farm scale in order to point out the changes occurred over
almost twenty years in the farms’ structure, management and production
features. The results showed that the major differences were related
to fertilisers management (clearly decreasing), to the reduction of
some crop types (industrial crops) and to the strong decrease of the
gross marketable production. Furthermore, apparently stable indicators,
such as the utilised agricultural area and the farm tractors’ power,
were actually the result of the compensation of contrasting trends.
Farmers’ behaviours were substantially homogeneous within the same
typology of farm, highlighting common evolution strategies. The desirability
of the occurred changes was also evaluated, underlining the
improvement of environmental sustainability of the current cropping
systems and a greater social acceptability of agricultural activities,
while the evaluation from the farmers’ point of view was less satisfactory
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