In protected areas of the Central Region of Brazil Melinis minutiflora (molasses grass, stinkgrass) is an important weed due to, among other reasons, its reproductively and dispersion. We evaluated spikelet sterility and seed viability and dormancy for two M. minutiflora cultivars (Roxo and Cabelo-de-Negro) collected in three conservation units in the Brazilian cerrado (hot, semi-humid savanna): Parque Nacional de Brasília, Distrito Federal; Reserva Ecológica do IBGE; Estação Ecológica de Águas Emendadas. The percentage of full seeds (i.e. those containing caryopsis) was evaluated by separating, counting and weighing full and empty spikelets, while seed viability and dormancy were evaluated using germination tests on full seeds. The collection site affected not only the percentage of full seeds, especially for cv. Roxo (17.5% to 36.1%), but also seed dormancy in both cultivars (20% to 80%) and seed viability in cv. Roxo (80% to 96%). Seed viability was adequately evaluated using germination tests in 0.5% (w/v) potassium nitrate at alternating temperatures (20 °C and 30 °C) in the light, while seed dormancy was adequately estimated in water at 25 °C in darkness. These results suggest that characteristics such as seed dormancy and high seed viability can contribute to the dispersion of M. minutiflora seeds in wildlife protection areas.
germination; spikelet sterility; weeds; wildlife protection areas
