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The objective of this research was to carry out a survey, through the levels of physical purity, percentage of pure seeds, number of other seeds, and the physiological quality through germination, in the samples of ryegrass seeds analyzed in laboratories accredited by the Ministry of Agriculture, Livestock and Supply in Rio Grande do Sul. Data from 3959 ryegrass samples analyzed from the period 2014 to 2017 were compiled. Quality of the seeds was presented through the percentage of samples within the standards recommended for commercialization, for the variables germination, pure seeds, seeds of cultivated species, wild, noxious, tolerated and noxiously forbidden, in all factors, cultivar, region of origin, category and crop of seed production. Quality of the lots of ryegrass seeds, analyzed by the laboratories of Rio Grande do Sul, obtained in the harvest of 2013 the lowest percentage of lots approved for commercialization, 57.96%, and the harvest of 2014, 2015 and 2016 with 89.60% 91.39% and 91.34%, respectively. In regions where livestock predominates, the percentage of ryegrass seed lots approved for commercialization was lower. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the practical application of herbicide, overseeded annual ryegrass for the establishment of forage peanut (Arachis pintoi) in natural vegetation. The experiments was conducted from October 2007 to November 2008, Estação Experimental Terras Baixas (ETB) - Embrapa Clima Temperado, Capão do Leão - RS. The treatments were arranged in a randomized block design in split plots with four replications. The plots were represented by the treatments with and without herbicide (3L ha-1 of commercial herbicide glyfosate). The subplots were defined by the absence of forage peanut, the presence of forage peanut, the presence of forage peanut overseeded with annual ryegrass. The frequencies of species of natural vegetation were not influenced by grazing and overseeded ryegrass. The establishment of forage peanut Arachis pintoi is benefited by the herbicide. However, it is a practice that causes a significant reduction of species of forage interest. The presence of annual ryegrass provides a favorable environment for forage peanut during the cool season. [ABSTRACT FROM AUTHOR]

In order to evaluate the satellite image patterns between such cool season cereals cultivated areas intended for grazing or grain production, Normalized Difference Vegetation Index (NDVI) temporal profiles were analyzed. This data was acquired from twenty nine wheat and annual ryegrass cultivated areas in the states of Rio Grande do Sul and Paraná. For each area, the cultivated species (wheat or ryegrass), as well as the respective central point coordinates, acquired via Global Positioning System (GPS) was informed. NDVI values were extracted over each monitored area from MODIS (Moderate Resolution Imaging Spectroradiometer) sensor images, with spatial resolution of 250 meters. The NDVI temporal profiles showed that grain production areas have a typical agricultural field spectral pattern. The same pattern was not observed for the grazing pasture areas. The differences observed in these temporal patterns are defined by the changes that grazing has imposed on the phenology and morphology of these plants. [ABSTRACT FROM AUTHOR]