Abstract:

This study was conducted to investigate the effects of various rootstocks on the total soluble protein content of pear scions, and to detect a polypeptide as a marker that would be associated with pear/quince compatibility/incompatibility. Bark samples were collected from 5 year-old pear scions grafted on QA and pear seedling rootstocks (PS). Total soluble protein contents of bark tissues of 4 pear scions, Passa Crassana (PC), Beurre Hardy (BH), Beurre Bosc (BB) and Bartlett (BT), were determined using the Bradford assay. Protein profiles of bark tissues taken from the graft combinations were determined using SDS-PAGE. In general, the scions grafted on QA had a greater total protein content than those on PS rootstock. The highest protein content was determined in BH/QA combination. However, no linear correlation was detected between total protein content and graft compatibility. In SDS-PAGE, the protein profiles of the scions were similar. However, a 63 kDa protein band determined in compatible pear scions (PC and BH) was faintly observed in an intermediate compatible scion (BB), but was not detected in the incompatible scion (BT). Our results indicated that this polypeptide could be associated with pear/quince graft compatibility/incompatibility.

Keywords: