Theme 12: Forage Breeding and Genetics
Description
Guineagrass (Panicum maximum Jacq.) is responsible for a high percentage of cattle finishing and milk production in Brazil, but presents problems of pasture degradability due to high soil fertility requirements and uneven production distribution. In order to search for new varieties to reduce these problems, over four hundred apomictic accessions of guineagrass and several sexual plants were introduced to Brazil in 1982. Agronomic evaluation took place at the National Beef Cattle Research Center of the Brazilian Agricultural Research Corporation (Embrapa Beef Cattle), in Campo Grande, MS, Brazil. Breeding of the apomictic species began in 1990 using sexual x apomictic crosses. Three sexual plants and five apomictic accessions were used in the crosses. Seventy-nine hybrids were evaluated in small plots, for forage yield, regrowth after cuts, flowering and vigor during three years. The best families were identified for each characteristic evaluated. Multivariate analysis using principal components grouped the hybrids into six clusters according to their production. Due to superior performance, hybrids in groups 6 and 2 (22 hybrids) were indicated for future regional trials in small plot evaluations and grazing studies, aiming at releasing new cultivars for pasture diversification in Brazil.
Included in
Evaluation of Guineagrass (Panicum maximum Jacq) Hybrids in Brazil
Guineagrass (Panicum maximum Jacq.) is responsible for a high percentage of cattle finishing and milk production in Brazil, but presents problems of pasture degradability due to high soil fertility requirements and uneven production distribution. In order to search for new varieties to reduce these problems, over four hundred apomictic accessions of guineagrass and several sexual plants were introduced to Brazil in 1982. Agronomic evaluation took place at the National Beef Cattle Research Center of the Brazilian Agricultural Research Corporation (Embrapa Beef Cattle), in Campo Grande, MS, Brazil. Breeding of the apomictic species began in 1990 using sexual x apomictic crosses. Three sexual plants and five apomictic accessions were used in the crosses. Seventy-nine hybrids were evaluated in small plots, for forage yield, regrowth after cuts, flowering and vigor during three years. The best families were identified for each characteristic evaluated. Multivariate analysis using principal components grouped the hybrids into six clusters according to their production. Due to superior performance, hybrids in groups 6 and 2 (22 hybrids) were indicated for future regional trials in small plot evaluations and grazing studies, aiming at releasing new cultivars for pasture diversification in Brazil.
