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Os acessos nativos do Rio Grande do Sul, “28B”, “26A”, “28C”, “26D” e “28E” de Paspalum nicorae e os ecótipos “Azulão” e “Baio” de Paspalum guenoarum foram avaliados com o objetivo de dimensionar a intensidade de associação da produção de matéria seca de folha com outros caracteres de interesse forrageiros nessas espécies apomíticas, testadas em diferentes anos e locais. O delineamento adotado foi o de blocos casualizados com três repetições em duas regiões fisiograficamente distintas. As avaliações foram realizadas por meio de cortes. As variáveis avaliadas foram a produção de matéria seca total, matéria seca de folhas, matéria seca de colmo, relação folha:colmo, índice de colheita e o número de afilhos. Correlações similares foram obtidas nos dois locais, qualificando a matéria seca de folhas como a de maior magnitude na relação direta e positiva à materia seca total. A análise de correlação geral demonstrou que a matéria seca de folhas e matéria seca de colmo forma alta correlação positiva para o incremento da matéria seca total. A produção da matéria seca total pode ser utilizada diretamente para seleção de genotipos em espécies do gênero Paspalum.

Chromosome number, meiotic behavior and pollen viability were evaluated in a collection of 53 Paspalumnicorae Parodi accessions, which are part of a breeding project of the species. All accessions are tetraploid, with 2n=4x=40.Despite the invariable chromosome numbers, there was variation among accessions in the frequencies of different chromosomeconfigurations at diakinesis and metaphase I, such as univalents, trivalents and quadrivalents. Other abnormalities asbridges and laggards were also observed at anaphase and telophase I. Meiotic indexes ranged from 82.00 to 99.50% andpollen viability from 88.99 to 95.06%. As the species is pseudogamous apomictic, fertile pollen is necessary for endospermformation. Results show that all plants are meiotically stable and have enough fertile pollen to be used as male parents incontrolled crosses.

The native accessions from Rio Grande do Sul of Paspalum nicorae, "28B", "26A", "28C", "26D" and "28E" and the accessions "Azulão" and "Baio" of Paspalum guenoarum were evaluated in order to measure the association of leaves dry matter yield with other traits of interest on these apomictic plants, tested in different years and locations. A completely randomized block design with three replications in two physiographically distinct regions was used. The evaluations of the agronomic traits was made under cuts. Total dry matter yield, leaves dry matter, stems dry matter, leaf: stem ratio, harvest index and number of tillers were determined. Similar correlations were obtained in both locations, with leaves dry matter yield showing the largest magnitude, affecting directly the total dry matter yield. Correlation analysis showed that overall the leaves dry matter and stems dry matter yield form a high and positive correlation affecting the total dry matter yield. The total dry matter yield can be directly used for selection of genotypes in the genus Paspalum. [ABSTRACT FROM AUTHOR]