Agradecimientos:A las diferentes autoridades de las instituciones participantes del proyecto INIA, FUCREA, FAGRO, CALCAR, SOFRILS, COLEME, SPLF, UTU - UTEC por apoyar este Proyecto durante el período 2017-2021 y en particular a los delegados de las mismas en la Comisión de Seguimiento del Proyecto, por su trabajo y contribuciones técnicas. Entre ellos a Carlos González, Andrés Barreira, Guillermo Fiol, Gustavo García, Eduardo Tornaría, Fabián Torres, Mauricio Rodríguez y Gustavo Alonso.

ABSTRACT.- Background and aims:Since 1750, the species-rich grasslands native to the Río de la Plata basin in southern South America have sustained low-input livestock production. Typically, these grasslands have low herbage phosphorus (P) concentration, and P deficiency in livestock is not rare. Worldwide, P fertilization is used to increase the productivity and nutritive value of grasslands, but it is unknown whether the Río de la Plata grasslands are limited by P availability.

ABSTRACT.- Rice is a crop that requires a large amount of water throughout its production cycle to ensure a good yield, resulting in higher water consumption compared to other crops. In Uruguay, about 160,000 ha/year are planted, requiring about 1,760 hm3/year of water, with a very high international average productivity of 9,000 kg/ha. Irrigation is generally carried out by surface/flooding, with water passing through dug channels where gates are used to regulate the flow, and in some cases measurement devices are installed.

ABSTRACT.- Furrow irrigation systems have been widely evaluated around the world. However, there is no national data indicating how efficient furrow irrigation is under Uruguayan conditions. The objective of the present work was to evaluate the performance of a system of furrow irrigation in two different soils texture. Seventeen irrigation events were analyzed in sugar-cane cultivation in northern Uruguay during 2016-17 and 2017-18 irrigation seasons. The water advance and recess curves were determined; flow rate during irrigation and runoff were monitored.

ABSTRACT.- Supplementing plants with silicon (Si) often improves plant productivity and resilience to biotic and abiotic stresses, but this is mostly reported in highly controlled experimental environments. The ecological consequences of Si supplementation, including environmental benefits and potential risks, are therefore poorly understood and require field-scale evaluation of how Si supplementation affects the wider ecosystem, such as invertebrate communities and soil physicochemical properties.

ABSTRACT.- Supplementing plants with silicon (Si) often improves plant productivity and resilience to biotic and abiotic stresses, but this is mostly reported in highly controlled experimental environments. The ecological consequences of Si supplementation, including environmental benefits and potential risks, are therefore poorly understood and require field-scale evaluation of how Si supplementation affects the wider ecosystem, such as invertebrate communities and soil physicochemical properties.

ABSTRACT.- Ramularia leaf spot (RLS) is primarily managed by foliar fungicide spraying, which can result in residues in the grain. In recent years, increasing attention has been paid to the risks these residues pose to consumers. This study aimed to evaluate the efficacy of fungicide management used for RLS control and their fungicide residues in barley grain.

ABSTRACT.- Changes in land use/land cover (LULC) directly or indirectly affect water quality in watercourses and impoundments. Sustainable management strategies aimed to enhance ecosystem health and community well-being require an accurate water-quality evaluation.

ABSTRACT.- Changes in land use/land cover (LULC) directly or indirectly affect water quality in watercourses and impoundments. Sustainable management strategies aimed to enhance ecosystem health and community well-being require an accurate water-quality evaluation.

ABSTRACT.- Context:In the temperate-humid region of Argentina, nitrogen (N) fertilisers in maize (Zea mays L.) are mainly applied around sowing, whereas N-splitting is rare and occurs during early vegetative stages. Splitting and late N fertilisation, even up to silking (R1), effects on yield have been recently studied. However, to the extent of our knowledge, these studies have mainly focused on the effect of these strategies on maize yield, but less on the crop N economy.