Allozyme segregation and inter-cytotype reproductive barrier in the polyploid complex Centaurea jacea

Controlled crosses were carried out within and between cytotypes of the Centaurea jacea complex. Progeny genotypes were looked at using allozyme markers to assess success of inter-cytotype crosses vs intra-cytotype ones to find out whether processes such as minority cytotype exclusion or inter-cytotype gene flow are likely to occur. Assessing the mode of inheritance of allozymes in tetraploids and checking for the occurrence of double reduction were goals. Null alleles were seen in the tetraploids at two enzymatic loci, so the expected difference of null allele frequencies between tetraploids and diploids were considered.