Seed quality shifts and managing plant genetic resources in fragmented landscapes

Trees promote long distance gene flow leading to the 'paradox of forest fragmentation genetics' - their populations are generally buffered against random genetic drift effects of habitat fragmentation commonly shown by other organisms. However, within fragmented landscapes, reduced stand density and changed plant-pollinator interactions are often observed to change individual plant mating patterns (e.g. outcrossing rates, pollen diversity). These mating patterns drive immediate gains or losses of genetic effect of negatively impacting the mating patterns of animal-pollinated trees and shrubs. With a case study of Australian mallee eucalypts, I use paternity analysis using microsatellites of open-pollinated progeny arrays to investigate how these mating patterns are a function of (1) stand density and (2) pollinator mobility. I then explore with case studies from the Australian mallee and the Neotropics how these mating patterns can directly impact on offspring fitness. The findings of this work have applications to management of plant genetic resources. I focus on the implications of these findings for the use of plant genetic resources in revegetation.