MORPHOLOGICAL-CHARACTERISTICS OF THE INTERSPECIFIC HYBRIDS BETWEEN JAPANESE APRICOT (PRUNUS MUME) AND PLUM (P-SALICINA)

Interspecific crosses between Prunus mume cv. Baigo (seed parent) and P. salicina cv. Sordum (pollen parent) were made in 1984 from which fo ur fertile seeds were obtained. When the seeds were planted in a green house in the following spring, three seedlings were obtained. Eventual ly, the seedlings flowered and set fruits;they proved to be interspeci fic hybrids based on peroxidase and esterase isozyme analyses. Morphol ogical characteristics of these seedlings are as follows. Mature leaf : General shape, tip and base form of the leaf and petiole color of th e seedlings are similar to 'Baigo' ; 'Sordum' and the seedlings have r eniform glands on their leaf base, but 'Baigo' has none. Flower : The newer size of seedlings was intermediate between 'Baigo' and 'Sordum'. 'Baigo' has one flower per flower bud, whereas 'Sordum' has two or th ree flowers. The hybrid seedlings bear one or two flowers per flower b ud and trichomes on the exocarp like 'Baigo', unlike 'Sordum' which ha s none. The pollen of the seedlings were fertile. Fruit : The shape of matured fruit of 'Baigo' and 'Sordum' is round;the latter has a sligh tly mounded tip. Two seedlings segregated to a round fruit and one int o an elliptical shape. Flesh color of 'Baigo' is yellow, whereas that of 'Sordum' is red. One seedlings segregated to a red flesh whereas tw o inherited a light yellow flesh.