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.

ABSTRACT. The potato crop (Solanum tuberosum L.) is of great importance in the Uruguay economy, being the major vegetable in volume of trade. Uruguay imports some amount of potato seed annually. The National Institute of Agricultural Research (INIA) has been engaged for the last decades to obtain cultivars more adapted to country agroecological conditions, easier to multiply locally for replacing imported seed cultivars such as 'Chieftain'. In this sense, promising cultivars including 'INIA-Iporá' were developed.

ABSTRACT. Supplementary irrigation in Citrus sinensis (L.) Osbeck 'Spring' navel and Citrus unshiu Marcow trees were studied according to fruit development stages on the northwestern region of Uruguay (32° S, 58° W) from 2000 to 2009. The effective rainfall (Pe) variability between consecutive years is bigger than the reference evapotranspiration (ETo) variability; despite the annual water balance seems to be adequate for excellent yields. Water deficit occurs at different intensities during fruit growth stages I, II and III.

ABSTRACT. Fertilizers application in irrigation water (Fertigation) is considered to be an efficient method of fertilizing fruit trees, but some information is needed on the relationship between irrigation depth and nitrogen (N). The objective of this work was to know the response of apple tree to different levels of irrigation depth based on maximum crop evapotranspiration (ET c) and N fertilization. The experiment was carried out in 2008-09 summer growing season of apple trees Malus x domestica Borkh 'Gala', with a row spacing of 4×1 m (2500 pl.

ABSTRACT. The aim of the study was to evaluate the antifungal activity of extracts of 10 plant species used in traditional Uruguayan medicine against the phytopathogenic fungus Alternaria spp. The plants were selected on the basis of their reported ethnobotanical uses. Aqueous, saline buffer and acid extracts of different plant species were screened in vitro for their antifungal activity against Alternaria spp. For the antifungal evaluation we used a microspectrophotometric assay.

ABSTRACT. Bemisia tabaci adults were collected from pepper and melon at different commercial production greenhouses in Argentina and Uruguay. The biotype status of adults was then established using cytochrome oxidase I gene (mtCOI) as molecular marker. Only the Q biotype was found on all plants sampled. This is the first report of the Q biotype in Argentina and Uruguay. © 2011 Springer Science & Business Media BV.

ABSTRACT. High midday temperatures in subtropical citrus growing regions can lead to excessively high leaf temperature (Tlf) and large leaf-to-air vapor pressure difference (D) in sun exposed leaves. This heat stress reduced net CO 2 assimilation (AC), growth, fruit yield and quality. 50% shading reduced average mid-day Tlf and increased AC, stomatal conductance (gs) and leaf water use efficiency, but decreased the internal concentration of CO 2 (Ci) in the mesophyll compared with sun-exposed trees throughout the season. However, shade had little effect on leaf transpiration.