Two experiments were conducted to examine woolly cupgrass seed reserve utilization and the effect of germination depth on seed reserve utilization, tiller number, and timing of tiller emergence. The first experiment included germination in light with water, in light with Hoagland's solution, and in darkness with water; the second included five planting depths of 1, 3, 5, 7, and 9 cm. Endosperm utilization and shoot and root growth over time were recorded. Endosperms lost weight rapidly until 6 d after germination (DAG), when weight loss slowed down. Endosperm weight loss ceased 8 or 10 DAG. Endosperm weight loss was fastest for germination in light with Hoagland's solution. Deep planting significantly decreased emergence rate and increased the time to emergence. Differences in residual endosperms may have affected the early development of woolly cupgrass seedlings. Germination from a depth of 9 cm depleted the endosperm by the time of emergence. Deep planting also decreased shoot dry weight and tiller number 15 d after planting (DAP). Because the first tiller of woolly cupgrass usually appeared 10 to 12 DAP, and the endosperm had been depleted before that, there was no endosperm to support the new tillers.
Nomenclature: Nicosulfuron; woolly cupgrass, Eriochloa villosa (Thunb.) Kunth. ERBVI.