Identification of Graft Incompatibility of Pear Cultivars on Quince Rootstock by Using Isozymes Banding Pattern and Starch

摘要

This research was initiated to survey the peroxidase isozyme profiles of 17 pear ( Pyrus communis L.) cultivars and compare their peroxidase profiles to Quince A (QA) ( Cydonia oblonga Mill.) rootstock. Additionally, samples from the graft union of pear cultivars and quince rootstocks were analyzed for peroxidase isozymes to identify possible association with compatible graft combinations. The total amount of starch content was also considered as another marker to identify the scion-rootstock compatibility. Two anodal peroxidase A (RF = 0.86), present in Beurre Hardy and QA and B (RF = 0.68), present in Beurre Hardy and absent in QA was considered as rootstock and scion relationship. The presence of A band in the graft union was an indication of compatibility of Beurre Hardy and Passa Crassana pear cultivars with QA, whereas, the absence of this band was related to incompatibility of Dargazi, Shahmivah and Torsh. Although the B band was present in Beurre Hardy, the absence of this band in QA was highly related to incompatibility of Shekari, Lizbon, Khoje asiabrak, Domkaj, Tabrizi, Koshia and Bolghari pear cultivars. The amount of starch accumulation near grafting sites (above and below) showed that Natanz, Dargazi, Shahmivah, Aloret and Torsh pear cultivars compared to others had greater amount of starch above the grafting sites.