03017nam a2200277 a 450000100080000000500110000800800410001910000150006024501110007526001120018652022270029865000140252565000130253965000130255265000120256565000120257770000260258970000150261570000140263070000170264470000140266170000180267570000130269370000160270670000170272210545832016-04-04       2015    bl uuuu     u01u1 u    #d1 aGLISON, N.  aResponses of seedling emergence of three Paspalum species to environmental factors.h[electronic resource]  aIn: International Symposium of Forage Breeding (5., Buenos Aires, AR), 19-21 Octubre, 2015. Abstract.c2015  aIn the warm?temperate regions of Uruguay and Argentina, the adoption of warm?season perennial grasses has been very limited. Slow and unpredictable establishment has been perceived as one of the most limiting factors for their use either as pure stands or in mixtures with cool season grasses. Among the best studied species are P. dilatatum and related species and P. notatum. In this study we analyzed a network of locations and sowing dates to understand the responses of these species to environmental factors and determine appropriate sowing dates. We evaluated a single clone or inbred line of P. dilatatum cv. Chirú, P. dilatatum ssp. flavescens, P. urvillei and P. notatum. Trials were established for two years in Montevideo, Salto and Tacuarembó in Uruguay and Buenos Aires in Argentina. In each location plots of three lines of 1.2 m were arranged in a split?split plot design with three replicates. Genotypes were randomized within dates within irrigated or non?irrigated main plots. Sowing dates were classified as early and late fall and spring (March, April, September and November, respectively). Based on the initial number of viable seeds, proportions of established plants were recorded 30 days after sowing. The ranking of the four genotypes was stable across environments (Chirú > Flavescens > Notatum > Urvillei) and the effect of irrigation was also significant on all of them. In non?irrigated plots emergence was mostly positively associated with cumulative rainfall and negatively associated to mean temperature. On irrigated plots on the other hand, rainfall did not show any effect and the response to mean temperature was best described by a bilinear function which reached its maximum at approximately 20ºC. These results suggest that this set of species may exhibit secondary dormancy at higher mean temperatures. A weak association between establishment and thermal amplitude was found for most genotypes, especially P. urvillei. In general early sowing dates showed the higher establishment ratios both for the fall and the spring. A better adjustment of sowing dates and selection for low?dormancy genotypes like Chirú, may facilitate the adoption of Paspalum species in this region.  aARGENTINA  aPASPALUM  aPASTURAS  aSIEMBRA  aURUGUAY1 aGONZÁLEZ BARRIOS, P.1 aCORREA, E.1 aVIEGA, L.1 aSALDANHA, S.1 aREYNO, R.1 aMUSACCHIO, E.1 aRUSH, P.1 aSCHRAUF, G.1 aSPERANZA, P.