36th International Carrot Conference Abstract

The potential impact of gene flow from cultivated carrots on the weediness of wild carrot populations.

Megan L. Van Etten and Johanne Brunet

MLV- Institute of Agriculture and Environment, Massey University, New Zealand; JB – USDA-ARS, VCRU, Madison, WI

Wild carrot, Daucus carota, is a weedy species in the U.S. where it can easily hybridize with cultivated carrot. In an effort to understand the impact of gene flow from cultivated to wild carrot populations, we have begun investigating the lifecycle and resulting population dynamics of wild carrot. Although it is considered a biennial, previous studies have suggested that at least some plants in a population exhibit an annual lifecycle, which could profoundly affect population growth. To further investigate the lifecycle, we chose focal plants from 2 populations near Madison, WI and traced their survival, reproduction and mortality for 2 years. We also obtained data on the timing and success of germination. Combining these data, we developed population matrix models to examine the impact of different life history stages on population growth. We observed that seeds from plants flowering early in the season can germinate in the same year and flower the next, thereby having a winter annual lifecycle. We modelled the effects of a shorter lifecycle on population growth and determined that it greatly increased population growth rate and the potential for weediness. In addition, we added data from previous studies on hybrids between cultivated and wild carrots to our matrix models to predict the effect of gene flow from cultivated to wild carrot populations on the population growth rate of wild carrots. These results highlight the potential impact of gene flow from cultivated carrots on the dynamics and weediness of wild carrot populations.

Last updated Thursday, 25-Jul-2013 11:53:17 CDT