Tuesday, November 6, 2007 - 3:45 PM
168-11

Evidence for a Non-Mendelian Mechanism Regulating Greens-type Poa annua L. Evolution.

Jonathan La Mantia, Pennsylvania State Univ., Pennsylvania State University, 116 Asi Building, University Park, PA 16802 and David R. Huff, Pennsylvania State University, 116 ASI Building, University Park, PA 16802.

Greens-type Poa annua L. has been noted as a species of turfgrass with great utility for golf course putting greens since the early 1920s. Nevertheless in the 80 years to present date, there has never been a stable, commercially available greens-type P. annua variety released to the market. Within the species P. annua, there exists a range of life history biotypes from robust annual types to dwarf perennial greens-types. Past research has documented that the traits which are unique to greens-type P. annua; stunted stem, leaf, and flower development, and delayed flower induction, have high broad-sense heritability and are linked. Our most recent research concurs with these prior findings, and suggests that the greens-type phenotype is regulated by a single genetic mechanism. However, greens-type x greens-type crosses have yielded somatic and germinal reversions to the annual-type morphology. Evidence will be presented that eliminates the possibility of out-crossing contamination and gene complementation, thus refuting a mendelian mechanism for these traits. Along with additional morphological, genetic, and molecular analysis, the results imply a non-mendelian, epigenetic mechanism that regulates the adaptative evolution of the greens-type Poa annua L.