Is low seed set of a forest wildflower due to lack of compatible mates? A test using long-distance pollinations.
Dr. Peter Scott of Indiana State University's Department of Biology, and undergraduate biology major Jason Wenning, are studying the reproductive biology of two Dicentra species in Mary Gray Bird Sanctuary. The title of our study is: Is low seed set of a forest wildflower due to lack of compatible mates? A test using long-distance pollinations.
Here is some background information and preliminary results of the study:
Dutchman's breeches (D. cucullaria) and squirrel corn (D. canadensis) are spring ephemeral wildflowers that flower in April. They are genetically self-incompatible, and set no seed unless suitable pollen is transferred by queen bumble bees. In west-central Indiana, near Terre Haute, IN, dutchman's breeches have very good seed set and squirrel corn does very poorly. We monitored the natural reproduction of both species at Mary Gray Bird Sanctuary (along the Tulip Poplar Trail) and also dug up some plants to use as long-distance pollen sources for Vigo County plants. Natural reproduction at Mary Gray yielded about 75% fruit set for dutchman's breeches, and 25% for squirrel corn; the number of seeds per flower averages 4 and 0.5, respectively. Thus, we documented the same big difference in fruit and seed set between the species as we had previously found in Vigo County. Long distance pollinations, relative to local pollinations, improved local fruit set slightly, but not markedly.
Submitted by P. Scott