Reproductive Ecology of the Sandhills Pyxie Moss (Pyxidanthera barbulata var. brevifolia) in North Caroline

摘要

Sandhills pyxie moss (Pyxidanthera Barbulata var. Brevifolia) is a creeping, evergreen subshrub of the sparsely wooded sandhills pine- dominated plant communities on Fort Bragg, North Carolina. This research described the breeding system of the sandhills pyxie moss, examined the pollination biology of the species, and assessed germination of the species. The breeding system was evaluated using experimental manipulations of pollen transfer on plants in their natural environment. The results indicate that sandhills pyxie moss is not self- compatible, but reproduction does not appear to be limited by pollinator availability. The existence of pollinators was studied through intensive observation, collection, and identification of insect visitors in the natural environment. The results indicate that bees, wasps, ants, and other insects visit and pollinate the sandhills pyxie moss, but ants appear to be the most important, effective pollinator in these study populations. Germination was tested by planting seed under greenhouse conditions. Sparse germination was observed from seed bank samples, but the viability of seedlings was very low. These results shed some light on the reproductive biology of sandhills pyxie moss, but do not establish evidence of successful sexual reproduction.