4 



F-statistics. Wright's F statistics were estimated for 

 the one polymorphic locus, Pai-2 : F, s = 0.57, F ST = 0.44, 

 and F =0.76. The four polymorphic populations showed a 

 significant deficit of heterozygotes at the Pgi-2 locus (F, s 

 = 0.57, chi square = 12.009, df = 4 , p = 0.0173). 



DISCUSSION AND CONCLUSIONS 



We examined 20 enzyme systems, and found 12 systems 

 that could be resolved consistently (Tables 2 and 3). Based 

 on allozyme banding patterns and previously published work, 

 we infer that these 12 enzyme systems code for 18 putative 

 loci. Only one locus was polymorphic in our population 

 samples. 



These populations of Arabis fecunda appear to be 

 partially inbred, and have very low levels of genetic 

 variability. There is a significant deficit of 

 heterozygotes (F, s = 0.57, p = 0.017), as is commonly 

 observed in self-compatible plants with self-pollination or 

 local mating among relatives. Arabis fecunda is autogamous 

 (habitually self-pollinating, Roberta Walsh, unpublished 

 data) . At the Pgi-2 locus there has been substantial 

 genetic differentiation between populations (Wright's 

 fixation index, F ST = 0.57). Again, these results are 

 typical of geographically isolated populations of partially 

 inbred plant species. We have not calculated indices of 

 genetic distance between populations, since an estimate 



