Ecotypic differences and performance of the genetic resources of cocksfoot(Dactylis glomerata L.) in north-west Spain

Quantitative traits and allozymes were used in two experiments to clarify t he ecotypic differentiation of natural cocksfoot (Dactylis glomerata) popul ations from north-west Spain. Thirty-nine populations belonging to the four main ecotypes in Galicia were cultivated in two field experiments. In the first experiment, there were significant differences between ecotypes for h eading date, flag leaf length, growth habit and vigour. Coastal populations were the least infected by rust. In the second experiment, allozyme marker s presumed to be diagnostic for ssp. glomerata vs. izcoi (TO1 1.00, TO1 1.0 3) were found in all populations studied (ten tetraploids and one diploid i zcoi). This suggests that gene flow occurs between coastal and interior pop ulations. Culm and panicle lengths of tetraploids (without application of f ertilizer) were inside the izcoi range in 1997, but some plants from all po pulations exceeded it in 1998. It is concluded that ssp. izcoi also occurs on the coast. Populations with a high level of complementary seasonal growt h were detected.