Pedicellate Spikelet Fertility in Big Bluestem from Eastern South Dakota

Within a nursery of big bluestem (Andropogon gerardii Vit.) from seed collections made in eastern South Dakota, 86% of the plants possessed fertile pedicellate spikelets. From 10 random culms of 462 plants representing 20 different collection sites, seed-bearing sessile and pedicellate spikelets were separated and weighed. A highly significant difference was found among sites for pedicellate spikelet seed yield. Fertile pedicellate yield was positively correlated (r = 0.69, P < 0.01) with total seed yield of ten culms. Pedicellate spikelet caryopses were smaller than sessiles from the same plant, suggesting they were of inferior quality.