Morphological classification and molecular marker development of white clover (Trifolium repens L.) parents and hybrids

White clover (Trifolium repens L.) is a perennial legume with various traits; it grows in temperate regions and has high potential as an ornamental plant. In the present study, four parental varieties (Ladino, Green Ice, William, and Dragon’s Blood) of white clover were classified based on 11 morphological traits [plant form, leaf shape, leaf edge shape, upper lamina color, lower lamina color, white V mark, midrib color, leaf patterns (front and back), flower color, and peduncle color]. Based on these traits, two hybrids were selected as follows: Ladino × Green Ice [hereafter referred to as Jeju Hapiness-1 (JH-1)] and William × Dragon’s Blood (JH-5). In addition, random amplified polymorphic DNA (RAPD) analysis was performed to confirm the molecular biological relationship between the parental varieties and hybrids. We confirmed to contain the polymorphic bands of the parental varieties at OPC13, OPD6, and OPG4 operon primers from JH-1, and at OPE10, OPG12, and OPH11 from JH-5. Further, the RAPD patterns from the hybrids were compared with the four parental varieties. A distinguishable RAPD pattern was identified in OPC13 and OPG4 from JH-1 and in OPG12 and OPH11 from JH-5. In addition, polymorphic DNA fragments in which the genetic relationship between the parental varieties and hybrids was confirmed were converted into sequence characterized amplified region (SCAR) markers. The morphological classification criteria, RAPD pattern, and SCAR marker are all considered useful for the classification and breeding of white clover and protecting varieties developed.