Morphological Characteristics of Interspecific Hybrids between Japanese Plum (Prunus salicina Lindl.) cv. Soldam and Apricot (P. armeniaca L.) cv. Harcot

摘要

Since 1999, interspecific crosses between Japanese plums and apricots have been made to breed new plumcot cultivars and to obtain basic data for stone fruit breeding at the National Institute of Horticultural & Herbal Science (NIHHS) of Rural Development of Administration (RDA) in Korea. A controlled interspecific cross between Prunus salicina Lindl. 'Soldam' (seed parent) and P. armeniaca L. 'Harcot' (pollen parent) was made in 1999, and 64 seeds were obtained. After sowing of those seeds in a greenhouse in the following spring, 23 seedlings were obtained. Eventually, 21 of 23 seedlings flowered, and 11 of 21 seedlings set fruits in 2006 and 2007. Morphological characteristics of these seedlings were investigated for two years. Whereas the leaf shape of 'Soldam' was elliptic and 'Harcot' was circular, 17 of 23 hybrid seedlings had obovate leaves and the others were circular like 'Harcot'. Thirteen seedlings bore white flowers like 'Soldam' and 8 seedlings bore pink flowers like 'Harcot'. All flowered seedlings had pubescent ovaries like 'Harcot'. Although 'Soldam' and 'Harcot' had abundant pollens, 11 of 21 flowered seedlings had no pollens. All fruits of seedlings had short fuzzy fruit skin. Six seedlings had red flesh color like 'Soldam' and 5seedlings had orange flesh color like 'Harcot'. Eight seedlings were clingstone like 'Soldam' whereas 3 seedlings were semi-clingstone. None of the seedlings were freestone like 'Harcot'. The mean of progeny for quantitative characters were near the parents' mean. However, progeny mean of leaf and peduncle lengths were shorter than parents' mean. The appearance and flavor of the interspecific seedlings were medium type between 'Soldam' and 'Harcot'. However, there were some seedlings with excellent fruit quality. The polymorphism of two SSR markers confirmed that all seedlings were real hybrids between Japanese plum 'Soldam' and apricot 'Harcot'.