Meiotic aberrations and pollen viability in Fuchsia species and hybrid

Abstract

The meiotic analysis of Fuchsia species revealed the incidence of a low frequency of univalents in diploids with less than 100% of pollen viability. Bivalent formation in the polyploid species such as F. hatschbachii, F. glazioviana, and F. boliviana with occasional univalents in F. magellanica suggests that these species are allotetraploids. In the hybrids, the extent of chromosome pairing at metaphase I was varied. The regular bivalent pairing observed in the interspecific hybrids of the diploid species suggests that F. fulgens, F. splendens, and F. triphylla all have homologous genomes with no structural heterozygosity differentiating them. The fertility in many hybrids is less than that of their parents which has been related to both chromosomal and genic sterility, a reflection of the meiotic irregularities. Reciprocal interchromosomal translocations that differentiate the parental chromosomes resulted in the formation of quadrivalents in some of the hybrids and these translocation heterozygotes showed reduced fertility (<50%).