ALLOZYME VARIATION WITHIN AND BETWEEN 3 POPULATIONS OF BROWNTOP (AGROSTIS-CAPILLARIS)

Allozyme variation in the tetraploid browntop (Agrostis capillaris) cu ltivar 'Grasslands Muster', and two resident hill country browntop pop ulations was investigated. The aim was to develop a set of genetic mar kers that would allow this cultivar to be reliably distinguished from the resident populations, enabling persistence of this cultivar in hil l country pastures to be monitored following oversewing. Screening of 17 enzyme systems yielded three polymorphic loci: Gpi; Pgm; and Mdh. F or Gpi, 12 alleles were found among the three populations sampled, all ele frequencies ranging from 0 to 0.245. Pgm showed six alleles, and f requencies ranged from 0 to 0.792. Mdh could only be analysed in terms of phenotype frequencies, and four phenotypes were recognised, with f requencies ranging from 0 to 0.6. Pairwise G-tests and the calculation of geometric distances between the populations on the basis of this d ata suggested that allele frequencies at the loci Gpi and Pgm differ s ufficiently between 'Grasslands Muster' and the resident populations t o allow reliable estimates of admixture proportions following oversewi ng, thus allowing monitoring of persistence in the pastures.