ABSTRACT:While low-cost technology can be applied within beef cattle systems to improve economic output and decrease economic risk, methodologies to increase adoption by farmers deserve attention. Here we report 4 case studies where low-cost, high-impact technology was applied on commercial farms in an endeavor to demonstrate increased physical output in what we describe as 'Producer Demonstration Sites'. Forage allowance (FA) affects forage growth, forage intake by animals and energy partitioning to maintenance or production.

Short-rotation plantations have been suggested to develop renewable energies in South America. Our study evaluated the biomass production of Eucalyptus benthamii, E. dunnii and E. grandis plantations at stocking densities of 2220, 3330, 4440 and 6660 trees ha-1 in the North (Tacuarembó) and West (Paysandú) of Uruguay, over a 76-month period. The species survival was not related to planting density, and the highest mortality rates occurred at Tacuarembó. The effects of tree competition were more evident for E. grandis.

ABSTRACT. The citrus family (Rutaceae) is a very complex and diverse source of carotenoids. Carotenoid profile and content varies greatly among different species, cultivars and even fruit tissues (e.g., flavedo and juice sacs). In Uruguay, the Citrus Breeding Program is focused on obtaining good quality seedless mandarin cultivars for the fresh market. One of the strategies to improve the nutritional value of citrus, is to increase the accumulation of antioxidant compounds in the fruit pulp.

ABSTRACT. Research at INIA Las Brujas has been focused to reduce insecticides input in fruit orchards. Mating disruption was the main tool developed to control oriental fruit moth (OFM), the major insect pest on peaches. No cover insecticide spray is necessary for early and midseason varieties, while for late varieties, two cover sprays are required to avoid OFM fruit damage. Mating disruption was also developed as a main tool, to reduce insecticide sprays on pears and apples, where codling moth (CM) is the major insect pest.

Nitrogen stable isotope (15N) natural abundance is widely used to study nitrogen cycling. In grazed ecosystems, urine patches are hot-spots of nitrogen inputs, losses, and changes in ?15N. Understanding ?15N dynamics in urine-affected vegetation is therefore crucial for accurate inferences from 15N natural abundance in grasslands. We hypothesized that leaf ?15N following urine deposition varies with time and plant functional group.

Nitrogen stable isotope (15N) natural abundance is widely used to study nitrogen cycling. In grazed ecosystems, urine patches are hot-spots of nitrogen inputs, losses, and changes in ?15N. Understanding ?15N dynamics in urine-affected vegetation is therefore crucial for accurate inferences from 15N natural abundance in grasslands. We hypothesized that leaf ?15N following urine deposition varies with time and plant functional group.

ABSTRACT. Agricultural systems integrating perennial grass-legume pastures in rotation with grain crops sustain high crop yields while preserving soil organic carbon (Cs) with low nitrogen (N) fertilizer inputs. We hypothesize that Cs saturation in the topsoil may explain the favorable C and N cycling in these systems. We tested this hypothesis by evaluating and simulating three contrasting crop and pasture rotational systems from a 20-year no-till experiment in Treinta y Tres, Uruguay.

ABSTRACT. Cyperus rotundus plants showing symptoms of root knot were observed in the municipality of Santa Maria, Rio Grande do Sul state, Brazil. Based on the morphological, esterase phenotypes and molecular analyses of rDNA-ITS and D2-D3 regions of 28S rDNA, the causal agents of the observed symptoms were identified as Meloidogyne graminicola, pathogenicity was confirmed by fulfilling Koch?s postulates. To our knowledge, this is the first report of M. graminicola in C. rotundus in Rio Grande do Sul State, Brazil. © 2019, Australasian Plant Pathology Society Inc.

ABSTRACT. Genotype and environment jointly determine yield and bread-making quality of bread wheat, being possible modulators for these characters. Eleven cultivars were grown at three different nitrogen regimes combining quantity and timing of nitrogen availability for two years; yield, grain protein concentration and Alveograph parameters were determined. Amount and size distribution of proteins were measured using Size Exclusion-High Performance Liquid Chromatography.

ABSTRACT. The dissipation of 4 commercial pre-harvest pesticides used in two Citrus species under field conditions is presented. The influence of agroecological region, the Citrus species and weather conditions on abamectin, spinosad, imidacloprid and difenoconazole dissipation rate on fruits were evaluated. A validated ethyl acetate method coupled to liquid chromatography-tandem mass spectrometry allowed the determination of pesticide residues having recoveries of 72?115%, relative standard deviations ≤16% and quantification limits below the international Maximum Residue Levels (MRLs).