GENETIC-LINKAGE BETWEEN RUNNERING AND PHOSPHOGLUCOISOMERASE ALLOZYMES, AND SYSTEMATIC DISTORTION OF MONOGENIC SEGREGATION RATIOS IN DIPLOIDSTRAWBERRY

As part of a strawberry (Fragaria sp.) genome mapping project, we stud ied the linkage relationship between runnering and phosphoglucoisomera se PGI-2 allozymes in diploid strawberry. The respectiver and Pgi-2 lo ci were found linked with a recombination frequency of 18.1% +/- 1.6% (a map distance of 18.9 +/- 1.6 cM). This is the second reported linka ge in strawberry. The linkage between runnering and phosphoglucoisomer ase allozymes, if conserved at the octoploid level, might provide a me ans of marker-assisted selection for the nonrunnering and bushy branch ing growth habits in cultivated strawberry. Severe distortion of monog enic segregation ratios was observed for runnering and PGI-2, and also for an unlinked locus for shikimate dehydrogenase allozymes. Alleles from the perpetual flowering (alpine F. vesca) parents were favored in this distortion. This phenomenon should be considered in future genet ic studies using crosses between alpine and nonalpine strawberries.