Description
Paspalum dilatatum Poir. (dallisgrass) is an excellent C4 forage for summer production, highly productive with a wide distribution within warm-temperate regions. P. dilatatum is native to South America with special relevance for milk and meat production since its forage quality is superior to that of other C4 forage grasses and it shows tolerance to frost and water stress. In situations of temperate and warm temperate climate, the presence of these species plays a key role in the ecological stability of the system due to the complementarity of the growth cycles between winter and summer grasses. Claviceps paspali (ergot) is a fungus that mainly parasitizes Paspalum spp., generating a structure called sclerotia, in which indole-diterpenoid alkaloids are isolated. Despite the excellent forage characteristics of Paspalum species, there is a need for the generation of varieties able to overcome two major limitations that were identified early on in this species, such as ergot susceptibility and seed production. With this objective, selected genotypes were crossed between apomictic and sexual species of different ploidy using P. malacophyllum as a source of immunity. Immunity to ergot has been evaluated in the field for two years in different representative regions of Uruguay and the accessions that did not get sick were selected as pollen donors. Crosses made with P. flavescens showed a germination percentage ranging between 1.7 and 7.09, while in P. dilatatum var. Chirú the range was reduced between 0.99 and 1.25 according to the employed parents. The hybrid nature of the progeny is being verified by microsatellites and functional markers associated with immunity and DNA content estimated by flow cytometry. This work aims to generate the basis to transfer immunity from P. malacophyllum in selected genotypes of Paspalum species predominant in Pampa biome and to improve seed production.
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Use of Genuine Sources of Ergot Resistance in Species of the dilatata Group of Paspalum
Paspalum dilatatum Poir. (dallisgrass) is an excellent C4 forage for summer production, highly productive with a wide distribution within warm-temperate regions. P. dilatatum is native to South America with special relevance for milk and meat production since its forage quality is superior to that of other C4 forage grasses and it shows tolerance to frost and water stress. In situations of temperate and warm temperate climate, the presence of these species plays a key role in the ecological stability of the system due to the complementarity of the growth cycles between winter and summer grasses. Claviceps paspali (ergot) is a fungus that mainly parasitizes Paspalum spp., generating a structure called sclerotia, in which indole-diterpenoid alkaloids are isolated. Despite the excellent forage characteristics of Paspalum species, there is a need for the generation of varieties able to overcome two major limitations that were identified early on in this species, such as ergot susceptibility and seed production. With this objective, selected genotypes were crossed between apomictic and sexual species of different ploidy using P. malacophyllum as a source of immunity. Immunity to ergot has been evaluated in the field for two years in different representative regions of Uruguay and the accessions that did not get sick were selected as pollen donors. Crosses made with P. flavescens showed a germination percentage ranging between 1.7 and 7.09, while in P. dilatatum var. Chirú the range was reduced between 0.99 and 1.25 according to the employed parents. The hybrid nature of the progeny is being verified by microsatellites and functional markers associated with immunity and DNA content estimated by flow cytometry. This work aims to generate the basis to transfer immunity from P. malacophyllum in selected genotypes of Paspalum species predominant in Pampa biome and to improve seed production.
