Publication Date
1989
Description
Brachiaria decumbens Stapf is a perennial tropical forage grass, native to east African savannas. It was introduced to Brazil in the 1960's and is now widely cultivated over 30 million hectares in Central Brazil alone. The two commercial varieties are apomictic tetraploids (2n = 4x = 36), producing uniform progeny, and were selected for their high dry matter production and persistence on poor acid soils. They lack, however, resistance to spittlebugs (Deois spp., Zulia spp., Aeneolania spp.) and produce forage of low nutritive value, especially during the dry winter months. The absence of natural variability associated to apomictic reproduction has prevented improvement of these varieties through hybridization. The Brachiaria germplasm recently collected by CIAT (International Center for Tropical Agriculture)/ILCA (International Livestock Center in Africa) under the auspices of IBPGR (International Board for Plant Genetic Resources) opens up new possibilities of selection of superior accessions and intra and interspecific breeding within this genus. The germplasm includes about 800 accessions of 24 different species of Brachiaria, collected over six countries in East Africa (Centro International de Agricultura Tropical, 1986). Breeding within this genus has been complicated by differences in ploidy levels between sexual and apomictic species (Ferguson, 1974), and by inherent difficulties in marking interspecific hybrids (Ndikumana, 1985). The study of the mode of reproduction of this B. decumbens germplasm was undertaken in hopes of finding sexuality and thus implementing an intraspecific breeding program aimed at producing superior apomictic cultivars to be released in Brazil.
Citation
do Valle, C B.; Savidan, Y H.; and Jank, L, "Apomixis and Sexuality in Brachiaria decumbens Stapf." (2025). IGC Proceedings (1989-2023). 55.
https://uknowledge.uky.edu/igc/1989/session3b/55
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Apomixis and Sexuality in Brachiaria decumbens Stapf.
Brachiaria decumbens Stapf is a perennial tropical forage grass, native to east African savannas. It was introduced to Brazil in the 1960's and is now widely cultivated over 30 million hectares in Central Brazil alone. The two commercial varieties are apomictic tetraploids (2n = 4x = 36), producing uniform progeny, and were selected for their high dry matter production and persistence on poor acid soils. They lack, however, resistance to spittlebugs (Deois spp., Zulia spp., Aeneolania spp.) and produce forage of low nutritive value, especially during the dry winter months. The absence of natural variability associated to apomictic reproduction has prevented improvement of these varieties through hybridization. The Brachiaria germplasm recently collected by CIAT (International Center for Tropical Agriculture)/ILCA (International Livestock Center in Africa) under the auspices of IBPGR (International Board for Plant Genetic Resources) opens up new possibilities of selection of superior accessions and intra and interspecific breeding within this genus. The germplasm includes about 800 accessions of 24 different species of Brachiaria, collected over six countries in East Africa (Centro International de Agricultura Tropical, 1986). Breeding within this genus has been complicated by differences in ploidy levels between sexual and apomictic species (Ferguson, 1974), and by inherent difficulties in marking interspecific hybrids (Ndikumana, 1985). The study of the mode of reproduction of this B. decumbens germplasm was undertaken in hopes of finding sexuality and thus implementing an intraspecific breeding program aimed at producing superior apomictic cultivars to be released in Brazil.
