INVESTIGATING THE PARENTAGE OF 'ORRI' AND 'FORTUNE' MANDARIN HYBRIDS
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. Orri mandarin is derived from Orah mandarin by induced mutation, and was reportedly bred by crossing Temple tangor and Dancy mandarin. Orri has excellent organoleptic qualities, and other favorable traits. With Dancy as the pollen parent, at least some degree of susceptibility of Orri to Alternaria brown spot (ABS) might be expected, but it is more likely to have inherited a high degree of susceptibility; yet Orri appears to be immune to ABS. SSR analysis provided evidence that excludes Dancy as the pollen parent of Orah. Further testing revealed the likely pollen parent candidate as Kinnow mandarin. Fortune 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 Clementine mandarin × Dancy cross. However, two independent molecular marker studies revealed that the pollen parent of Fortune is possibly Orlando tangelo and not Dancy. In both cases, the pollen parent of Orri and Fortune mandarin hybrids appears not to be Dancy as published. This information will assist geneticists and breeders to re-interpret heritability studies on ABS susceptibility of mandarins and their hybrids.
Graham H. Barry, , Frederick G. Gmitter Jr., , Chunxian Chen, , Mikeal L. Roose, , Claire T. Federici, and Gregory T. McCollum, (2015). INVESTIGATING THE PARENTAGE OF 'ORRI' AND 'FORTUNE' MANDARIN HYBRIDS. Acta Hortic. 1065, 449-456
Citrus reticulate, Alternaria brown spot, heritability, molecular markers, SSR