Tannat grape composition responses to spatial variability of temperature in an Uruguay's coastal wine region.

Spatial variability of temperature was studied in relation to the berry basic composition and secondary compounds of the Tannat cultivar at harvest from vineyards located in Canelones and Montevideo, the most important wine region of Uruguay. Monitoring of berries and recording of temperature were performed in 10 commercial vineyards of Tannat situated in the southern coastal wine region of the country for three vintages (2012, 2013, and 2014). Results from a multivariate correlation analysis between berry composition and temperature over the three vintages showed that (1) Tannat responses to spatial variability of temperature were different over the vintages, (2) correlations between secondary metabolites and temperature were higher than those between primary metabolites, and (3) correlation values between berry composition and climate variables increased when ripening occurred under dry conditions (below average rainfall).

Impact of change in winter strategy of one parasitoid species on the diversity and function of a guild of parasitoids.

The rise of temperatures may enable species to increase their activities during winter periods and to occupy new areas. In winter, resource density is low for most species and an increased number of active consumers during this season may produce heightened competitive pressure. In Western France, the aphid parasitoid species Aphidius avenae Haliday has been known to adopt a winter diapausing strategy adjacent to newly sown cereal crops, until recent reports of active winter populations in cereal crops.