An isoenzyme study in the genus Lotus (Fabaceae) : Segregation of isoenzyme alleles in synthetic allo- and autotetraploids, and in L. corniculatus.

Segregation of the cytosolic Pgi2 locus was studied among progeny of the synthetic allotetraploid (L. japonicus × L. alpinus)(2), the synthetic autotetraploid (L. alpinus)(2), and the cultivated tetraploid species L. corniculatus L. Evidence of an original diploid duplication found within the interspecific hybrid L. japonicus × L. alpinus was also found within the synthetic allotetraploid (quadruplication of loci). Evidence suggesting quadruplication of loci was also found in the tetraploid L. corniculatus, but not in the synthetic autotetraploid (L. alpinus)(2). It is suggested that the original duplication resulted from unequal crossing-over between homoeologues and that it provides evidence that L. corniculatus is a segmental allotetraploid. Quadruplication of loci in L. corniculatus could explain previously reported distorted tetrasomic ratios for segregation of qualitative characters in this species.