El análisis de la dinámica de la respuesta en desempeño animal a la suplementación invernal sobre campo natural, en una amplia serie de experimentos, reveló marcadas diferencias en su fase inicial. Específicamente, la presencia o no de un período de entre 400 y 800 grados.día* durante el cual la suplementación no mejora el desempeño animal y que, por ende, impacta negativamente en la eficiencia. En parte, estas diferencias están asociadas a la disponibilidad de forraje, la tasa de sustitución y el clima.

ABSTRACT.- Southeast Asia (SEA) is a key producer and exporter of rice, accounting for around 28% of rice produced globally. To effectively mitigate greenhouse gas (GHG) emissions in SEA rice systems, field methane (CH4) and nitrous oxide (N2O) emissions have been intensively studied. However, an integrated assessment of system-level GHG emissions which includes other carbon (C) balance components, such as soil organic carbon (SOC) or energy use, that can positively or negatively influence the net capacity for climate change mitigation is lacking.

ABSTRACT.- Southeast Asia (SEA) is a key producer and exporter of rice, accounting for around 28% of rice produced globally. To effectively mitigate greenhouse gas (GHG) emissions in SEA rice systems, field methane (CH4) and nitrous oxide (N2O) emissions have been intensively studied. However, an integrated assessment of system-level GHG emissions which includes other carbon (C) balance components, such as soil organic carbon (SOC) or energy use, that can positively or negatively influence the net capacity for climate change mitigation is lacking.

Most plant pathogens exhibit host specificity but when former barriers to infection break down, new diseases can rapidly emerge. For a number of fungal diseases, there is increasing evidence that hybridization plays a major role in driving host jumps. However, the relative contributions of existing variation versus new mutations in adapting to new host(s) is unclear. Here we reconstruct the evolutionary history of two recently emerged populations of the fungus Pyricularia oryzae that are responsible for two new plant diseases:wheat blast and grey leaf spot of ryegrasses.