Chromosome Pairing Behaviour in the Interspecific Hybrids of Dendrobium Section Spatulata

摘要

The species in section Spatulata of Dendrobium have colorful, attractive and long-lasting flowers that have been introduced into breeding programs for potted plants and cut-flower market.In this study, we investigated the meiotic chromosome pairing in some new interspecific hybrids of Dendrobium section Spatulata.At metaphase I of meiosis, the pairing of parental chromosomes was mostly as bivalents in the intra-section hybrids and some inter-section hybrids, providing the opportunity for recombination to take place between the two component genomes.Consequently, high frequency of normal sporad (spore tetrad) was observed,suggesting that high fertility of these hybrids.High frequency of homoeologous chromosome pairing would guarantee genome introgression of parental species in these interspecific hybrids when they were used in subsequent breeding programs.