ISSR analysis of Asclepias tuberosa from seven different locations throughout the contiguous United States.

Yourha Kang, Dept. Biology, Iona College, New Rochelle, NY 10801

Butterfly weed (Asclepias tuberosa) is a plant known for its bright-orange flowers, its medicinal properties, and as the name suggests, its ability to attract butterflies, including the famous migratory monarch butterflies. The plant is found in most of the contiguous Unites States (US), somewhat mimicking that of the range of the monarch butterflies. Its flowers provide nutrition for the mature monarch insects, and the insects lay their eggs on the underside of the leaves; the hatched larvae then eat the leaves and incorporate the plant’s secondary metabolites into their own defense against predators. This research is investigating the genetic diversity of A. tuberosa from different parts of the United States. This is to determine if the butterfly weed in the US constitutes one large interbreeding population, or if plants that are geographically separated by large distances are evolving as isolated populations and are becoming genetically distinct. To do this, I am analyzing inter-simple sequence repeat (ISSR) markers from 80 leaf samples taken from sites in New York, Florida, Iowa, Ohio, Oklahoma, Tennessee and Virginia. ISSR analysis is a PCR-based technique (like many techniques analyzing DNA) that relies on polymorphisms in hypervariable repeat sequences in the genomes of the organisms being studied. Results from the ISSR analysis will be presented and discussed.