Patterns of amplified restriction fragment polymorphism in natural populations and corresponding seed collections of plains rough fescue (Festuca hallii)

Abstract

Plains rough fescue ( Festuca hallii (Vasey) Piper) is a dominant native grass species in the Fescue Prairie region of North America that has undergone dramatic range reduction in the past century. Little is known about the genetic diversity of this species. The amplified restriction fragment polymorphism (AFLP) technique was applied to assess the comparative genetic diversity of six plains rough fescue populations in Manitoba and Saskatchewan and their corresponding seed collections. Three AFLP primer pairs were employed to screen 529 samples, representing about 30 samples each of reproductive tiller, vegetative tiller, and seed collected from each population. A total of 330 polymorphic AFLP bands were scored for each sample; their occurrence frequencies ranged from 0.01 to 0.99 and averaged around 0.47. Analysis of molecular variance revealed more than 90% of the total AFLP variation resided within natural populations (reproductive and vegetative tillers) and within seed samples. Four populations sampled from protected areas appear to have relatively lower within-population variation than two unprotected populations. Only 0.2% AFLP difference was revealed among the three tissue types examined. The tiller samples revealed slightly larger among-population variation than the seed samples and captured substantial associations of AFLP variation with population geographic distances. These findings are important for germplasm sampling for ex situ conservation, are useful for germplasm development for pasture seeding, and should facilitate the management of fragmented fescue populations.