Inbreeding depression in wild maize populations (Zea mays ssp. parviglumis) subject to habitat degradation in southwest Mexico
Date
2018-05
Authors
Schulz, Aimee
Major Professor
Advisor
Hufford, Matthew
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Crops were domesticated from wild taxa, in many cases, thousands of years ago. These wild progenitors can still be found and serve as a source of variation for the genetic improvement of modern varieties. However, the realization of this genetic potential depends critically on the conservation of wild populations. Concerns regarding habitat degradation and the overall decline of wild maize populations have prompted this study. Five populations of Zea mays ssp. parviglumis collected in Jalisco, Mexico were planted in a common garden. Eleven traits correlated with plant fitness were measured. Previously generated microsatellite genotypes of the five populations were evaluated to determine levels of neutral genetic diversity. Plants whose seed were sourced from larger populations had greater genetic diversity and possessed phenotypic traits associated with higher fitness, while plants sourced from smaller populations had traits characteristic of lower fitness. Plants from larger populations germinated more quickly, reached anthesis sooner, demonstrated a higher level of photosynthetic activity, and produced more biomass, suggesting a direct correlation between fitness of a population and genetic diversity. These results emphasize the importance of preserving large populations of parviglumis to limit inbreeding depression and maintain the genetic diversity and adaptive potential of this germplasm.
Series Number
Journal Issue
Is Version Of
Versions
Series
Series
Academic or Administrative Unit
Type
Presentation