Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: 4/27/1999
Publication Date: N/A
Citation: N/A Interpretive Summary:
Technical Abstract: Simple sequence repeats (SSRs) are highly polymorphic regions of DNA that can be used for the molecular characterization of apples (Malus) germplasm. SSR markers are sufficiently variable to distinguish between individual plants of wild Malus species. In this study, accessions of Malus hupehensis were screened for fragment length variation in PCR amplified simple sequence repeat regions of DNA. The fragment length phenotype produced by five SSR primer pairs showed no variation between two lineages of M. hupehensis collected in the Changjiang (Yangste) River valley. One lineage was collected in 1908 by E.H. Wilson near the city of Ichang, Hubei Province. The second lineage was collected by cooperators at China's Southwest Agricultural University (SWAU) in 1997 near the city of Chongqing (Chungking). M. hupehensis Plant Introduction No. 588760 from the National Plant Germplasm System lacks provenance, but displays a fragment length phenotype identical to both the Wilson and SWAU lineages. The spread of a clone may be aided by asexual reproduction through seed, which is not uncommon in polyploid apples. Two seedlings each of the 15 maternal trees from the SWAU lineage were assayed for ploidy level by flow cytometry. The DNA content per nucleus for all SWAU progeny fell within the range of triploids, 2.19 to 2.68 pg DNA/nucleus. It appears that plant explorers in China separated by almost 90 years have succeeded in sampling a single clonal lineage of M. hupehensis.