Identification of Plum × Peach Hybrids by Isoenzyme Analysis

Two isoenzyme systems, glucose phosphate isomerase and phosphoglucomutase, were identified for use as starch gel electrophoretic markers of plum × peach ( Prunus salicina × Prunus persica ) interspecific hybrids. Two distinct regions of banding were associated with each enzyme system. Different unique banding patterns for each species were observed for plum and peach at 3 of 4 banding regions. Interspecific hybrid plants exhibited hybrid enzyme patterns with bands from both plum and peach in each region. Consequently, interspecific plum × peach hybrid genotypes may be distinguished from parental plum or peach genotypes. These enzyme systems may be used in breeding programs to identify plum × peach hybrid seedlings.