|Joung, Young Hee|
Submitted to: Journal of Horticultural Science and Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/2/2003
Publication Date: 5/15/2004
Citation: Joung, Y.H., Roh, M.S. Paternity Determination of Ornithogalum Seedlings Using DNA Markers. Journal of Horticultural Science & Biotechnology. 2004. v:79(2), pp:316-321. Interpretive Summary: Most of the horticultural cultivars with desirable characteristics are propagated vegetatively by taking cuttings from stems or by dividing bulbs to maintain the desirable characters. New cultivars are created from seeds that were produced after controlled pollination. However, sometimes uncontrolled pollination or cross pollination occurs when different cultivars or species are grown together in the same location. Ornithogalum is a new plant for cut flower and also for potted plant production. When Ornithogalum 'Chesapeake Starlight' was grown for several years in the greenhouse, no seeds were produced without artificial pollination. However, in one instance seeds were obtained without pollination. Seedlings were grown to flower. At flowering, there was a difference in height, flower colors and particularly in the presence and absence of pollen. This variation could result from self-pollination or cross pollination. Since seeds were not produced for many years, it can be concluded that cross pollination occurred. Molecular markers were used to show that the source of pollen was other short Ornithogalum species that were grown in the greenhouse. This technique can be used to identify the source of pollen and also to trace the origin of the plants in question.
Technical Abstract: This research was initiated to identify the parentage of putative Ornithogalum hybrids using DNA fingerprinting techniques. Seeds were harvested from Ornithogalum thyrsoides 'Chesapeake Starlight', and 5 seedlings (SD1-SD5) were selected and evaluated for growth, flowering, and DNA fingerprinting. Ornithogalum conicum, Bokbaai type of O. thyrsoides 7050A, 7050B and a seedling from a cross between O. conicum x 7050C which were considered as a possible paternal parent of the seedlings were also analyzed. These seedlings varied in scape length, flower shape and color, and the presence or absence of pollen. A total 169 random amplified polymorphic DNA (RAPD) bands were produced, of which 90 (53 %) were polymorphic. Based on the p-distance value, O. conicum was excluded as a potential source of pollen and Bokbaai type of Ornithogalum 7050 was considered as pollen source. However, the possibility that all seedlings could result from self-pollinated progenies of 'Chesapeake Starlight' was not excluded. Five randomly selected primer pairs for amplified fragment length polymorphism (AFLP) analysis generated total 298 fragments, of which 191 (63.4 %) were polymorphic bands. The presence of marker 109 in all four seedlings, SD1, SD 2, SD 4, and SD 5 and in O. conicum x 7050C concludes that marker 109 was inherited from 7050C. According to the p-distance and nonmaternal band analysis performed with RAPD and AFLP, it was concluded that the seedlings were not the result of self-pollination, and O. thyrsoides 7050C could be the paternal parent. Ornithogalum thyrsoides, instead of O. conicum, should be used in the future breeding efforts to breed a paper white flower with cup-shaped florets.