Philip Sheridan1,2 and David Karowe2
The Yellow Pitcher Plant, Sarracenia flava L., is an insectivorous plant restricted to fire maintained wetland ecosystems in southeastern Virginia. Only six scattered sites remain in the state with an average population of thirty-six clumps covering a quarter of an acre each. One site each from Dinwiddie, Prince George, and Nansemond Counties was tested for the effect of self-pollination (inbreeding), intra-site and inter-site outcrossing on total seed number, total seed weight, and average seed weight. In all sites, self-pollination resulted in significantly lower total seed number and total seed weight. Means for self-pollinated capsules were approximately one-fourth the yield of outcrossed capsules: this suggests strong inbreeding depression in all 3 sites. For Dinwiddie plants however, total seed number was significantly lower for inter- than for intra-site outcrossed capsules but the reverse was observed for Nansemond plants and there was no difference among the Prince George plants. Such a pattern might arise if S. flava populations differed in the extent of adaptation to local site conditions.1. Meadowview Biological Research Station and
2. Department of Biology, Virginia Commonwealth University.