ABSTRACT. Grapefruits are among the citrus species more sensitive to cold and develop chilling injury symptoms during prolonged postharvest storage at temperatures lower than 8 C?10 C. The plant hormone ethylene has been described either to protect or potentiate chilling injury development in citrus whereas little is known about transcriptional regulation of ethylene biosynthesis, perception and response during cold storage and how the hormone is regulating its own perception and signaling cascade.

ABSTRACT. Uruguay is one of the countries with favorable conditions for the development of olive tree culture. Olive oil is mainly composed by triglycerides, formed by different fatty acids which confer a main portion of its properties. Its acidic composition varies mainly with variety, local climatic conditions and fruit maturity degree. The objective of this work is to know the influence of fruit maturity stages on the fatty acid profile in the ?Arbequina? and ?Picual? varieties cultivated in Uruguay.

ABSTRACT. The carotenoid content and profile evolution of Uruguayan Tannat grapevine fruit was studied. Two differently managed vineyards exposed to different sunlight and temperature conditions were sampled over two successive ripening periods. Seven carotenoids were identified by HPLC-DAD:neoxanthin, violaxanthin, luteo-xanthin, lutein 5,6-epoxide, flavoxanthin, lutein, and ?-carotene. Irrespective of species, the highest carotenoid concentrations were found at initial sampling, immediately decreasing sharply to a minimum at harvest.