Fingerprinting trifoliate orange germ plasm accessions with isozymes, RFLPs, and inter-simple sequence repeat markers

摘要: Trifoliate orange [Poncirus trifoliata (L.) Raf.] is frequently used as a parent in citrus rootstock breeding, but the origin and amount of genetic diversity germ plasm collections are poorly understood. Most accessions self-compatible, produce mixture sexual apomictic seedlings. Variation among 48 vegetatively propagated trifoliate was assessed at seven isozyme loci, together with restriction fragment length polymorphisms (RFLPs) detected by 38 probe-enzyme combinations inter-simple sequence repeat (ISSR) markers generated 11 primers. Isozymes RFLPs few accessions, although analysis has shown that common phenotype heterozygous for four least RFLP loci. ISSR amplification multiple banding profiles an average 58 fragments/primer/accession. These fragments were repeatable across DNA samples extracted from different trees same accession or times, separate PCR runs. Seventeen unique marker phenotypes identified. The classified into major groups based on polymorphic markers. All large-flowered group 4, while small-flowered 3. Many segregated progeny derived open-pollination (probably mostly selfing) accession, indicating these also heterozygous. Accessions having identical genotypes large number unlikely to have diverged recombination. Thus limited divergence we most likely originated mutation. ‘Monoembryonic’ ‘Simmons’ differed other only loss specific markers, they zygotic seedlings individuals similar genotype. Three recently introduced China relatively fingerprints 3–14 probably represent much more divergent may be valuable breeding resource.