Gene flow (pollen and seed) in fragmented populations of plants

Abstract

Nora, S., Albaladejo, R.G., González-Martínez, S.C., Robledo-Arnuncio, J.J., Aparicio, A. (2011). Gene flow (pollen and seed) in fragmented populations of plants. Ecosistemas 20(2-3):35-45

Fragmentation is a process of habitat transformation (including a reduction in extension and quality) which leads to an unavoidable loss of biodiversity.  Further,  reduced population  sizes  promote  inbreeding,  genetic  drift  and  genetic  impoverishment.  In  the  whole  life  cycle  of seeding plants, only pollen grains (haploid gametophyte) and seeds (diploid sporophyte) have dispersal capability. So, the genetic fate of plant  populations  depends  on  breeding  (autogamy  vs.  xenogamy)  and  dispersal  systems  both  within-  and  among-  individuals  and populations. Consequently, pollen and seed dispersal inherently determinates both ‘quantity’ and ‘quality’ (i.e. diversity and fitness) of gene flow. Gene dispersal studies are pivotal for conservation biologists because they  help to understand the  actual consequences of fragmentation and to delimit  conservation units. Due to the complexities of the underlying processes, gauging  gene  flow  across  natural populations is a great challenge that extends beyond single study fields and needs from multidisciplinary approaches.