Genotypic differentiation on an individual level in Gagea villosa(M.BIEB.) DUBY, Gagea lutea (L.) KER-GAWLER and Gagea bohemica subspsaxatilis (KOCH) PASCHER in Saxony-Anhalt using RAPD markers

摘要

We demonstrate that the RAPD technique is a powerful method for analysing the genetic population structures of different Gagea species (Liliaceae). DNA was isolated from individual plants of the species G. villosa, G. lutea, G. bohemica subsp. saxatilis, and G. pratensis from different locations in Saxony-Anhalt. A RAPD pattern was established using four appropriate random primers and this RAPD pattern appeared to be characteristic for the four Gagea species. A characterization of genotypes was possible on an individual level. It is the first investigation of Gagea in which the ecological and genetic aspects of population structures were combined. Among the investigated Gagea species there is a clear difference in the number found in the study area, in habitat requirements, in the potential for colonization of new habitats and also in their genetic variability. G. villosa and G. lutea represent large populations with a high level of genetic polymorphism (78,8% and 71,4%) among populations. The level of polymorphism within the investigated populations was 37% to 60% for G. viliosa and 16% to 48% for G. lutea. Previously in Saxony-Anhalt there were large populations of G. villosa in arable land, but as a result of the intensification of agriculture there has been a decrease in the number of populations. Other populations of this species have been successful in occupying new habitats with a high level of genetic variability of those populations. In contrast G, bohemica subsp, saxatilis occurred in low numbers for a long time in isolated populations which has lead to a loss of genetic variability. Within the populations only 2,5% to 6,2% polymorphic RAPD markers was found. The level of polymorphism among the G. bohemica populations was however 39,6%. The small populations of G. bohemica subsp. saxatilis have little genetic Variation and should be protected.