Seed Quality as Related to Harvest Time in Three Key Perennial Grasses Native to Puna Tussock Rangelands of Peru

Seed-based rehabilitation programs represent a primary foundation for rangeland recovery, which requires high-quality seed of key native species. The objective of this research was to determine the seed quality at different harvest times for three key perennial grasses native to puna tussock rangelands of Peru: Festuca dolichophylla, Festuca humilior, and Calamagrostis vicunarum. Seeds of each species were harvested at 21, 28, and 35 days after anthesis and evaluated by standard tests to determine the purity, size, viability, and germinability. On average, the seed purity of the studied species ranged between 23% and 44%, hundred-seed weight between 34 mg and 73 mg, seed viability between 24% and 60%, and the seed germination between 18% and 34% over the harvest dates. The highest seed quality was observed in C. vicunarum. Seed quality parameters of the studied species did not show a consistent variation over the harvest times. Overall, the species studied presented relatively low seed quality; therefore, when using it in rehabilitation programs for rangeland recovery, it is important to carry out a previous cleaning process (to reduce nonviable seeds and inert matter) and to use a sufficient quantity of seed for effective establishment of these key grasses.