The Study of Variation of Phloridzin Content in Six Wild Malus Species

Phloridzin is relatively abundant in species of genus Malus Miller, of which China is the most important origin and diversification center. In this study, phloridzin contents in fruits and leaves of six wild Malus species were analyzed using a RP-HPLC system. The phloridzin content varied significantly among species. The highest phloridzin content in fruits was found in M. xiaojinensis (0.63 mg/100mg), whereas the lowest in M. maerkangensis (0.04 mg/100mg); meanwhile, the highest phloridzin content in leaves was found in M. transitoria (14.36mg/100mg), whereas the lowest in M. kansuensis (4.08 mg/100mg). Interestingly, phloridzin content showed no significant distinction among different populations of M. toringoides, however, there is a wide range of variation among individuals of the same wild Malus species. Different genetic constitution is the most likely reason for variation of phloridzin content among species, whereas variation among individual may be caused by heterogeneous environmental factors. Our preliminary study provides important information for potential novel utilization of wild apple germplasm in China.