2015/01/01 by Graham H. Barry, Frederick G. Gmitter, Chunxian Chen +3 · 1 voice · 1 citation
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · #Fungal Plant Pathogen Control #Plant Pathogens and Fungal Diseases #Plant Physiology and Cultivation Studies
paper · doi:10.17660/actahortic.2015.1065.55
openalex publication_date 2015/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
Germplasm characterization is now possible and more reliable using improved molecular markers and genomic tools. Previously citrus cultivars were primarily described according to their morphological or horticultural traits, but trueness-to-type can now be confirmed using molecular markers, thereby limiting inadvertent cultivar misidentification. Following routine testing the reported parentage of two mandarin hybrids is now questioned. âOrriâ mandarin is derived from âOrahâ mandarin by induced mutation, and was reportedly bred by crossing âTempleâ tangor and âDancyâ mandarin. âOrriâ has excellent organoleptic qualities, and other favorable traits. With âDancyâ as the pollen parent, at least some degree of susceptibility of âOrriâ to Alternaria brown spot (ABS) might be expected, but it is more likely to have inherited a high degree of susceptibility; yet âOrriâ appears to be immune to ABS. SSR analysis provided evidence that excludes âDancyâ as the pollen parent of âOrahâ. Further testing revealed the likely pollen parent candidate as âKinnowâ mandarin. âFortuneâ mandarin was a popular late-maturing mandarin cultivar until the high incidence of ABS rendered the cultivar uneconomical to produce in certain citrus production regions. This exceptionally late, high quality, attractive cultivar is reported to have originated from a âClementineâ mandarin A âDancyâ cross. However, two independent molecular marker studies revealed that the pollen parent of âFortuneâ is possibly âOrlandoâ tangelo and not âDancyâ. In both cases, the pollen parent of âOrriâ and âFortuneâ mandarin hybrids appears not to be âDancyâ as published. This information will assist geneticists and breeders to re-interpret heritability studies on ABS susceptibility of mandarins and their hybrids.