高位嫁接提高库尔勒香梨越冬性的初步研究

研究香梨高位嫁接后树体结构特征和高位嫁接提高香梨越冬性的生理机制。结果表明,在杜梨上进行"三主一心"高位嫁接香梨后,形成的树体结构表现为各大主枝基角较单芽低位嫁接法增大1倍,腐烂病的田间发病率显著下降,树体抗冻性明显提高,生长势增强,植株的丰产性和稳产性显著提高。-20℃可作为香梨树体可忍受的极限低温。1a生枝条的组织含水量和可溶性糖质量分数两个指标可很好地表征抗寒性提高的生理机制,高位嫁接产生的养分截流作用是香梨越冬性提高的根本原因。

Increasing Cold Hardiness of Kuerle Fragrant Pear (Pyrus bretschneideri ) by Top grafting

Kuerle fragrant pear(Pyrus bretschneideri) is an elite pear variety native to Xinjiang Uygur Autonomous Region,China.In last decades,freeze injury frequently happened to Southern Xinjiang damaged greatly the sustainable development of pear industry.The physiological mechanism involving in increasing winter hardiness of pear by top-grafting was studied in the paper.The results were as following: The tree structure from grafting on three branches and one stalk of rootstock was greatly different from a traditional one by a one-bud grafting.The angles of branches doubled.The occurrence of canker decreased significantly.Due to the improvement of cold resistance and growth power,the productivity and yield stability increased greatly by top-grafting.-20 ℃ could be served as the lowest survival temperature of pear.Tissue water content and soluble sugar content in one-year shoots were two ideal physiological parameters to describe cold resistance.Higher-grafted trees had a higher soluble sugar content than the common trees as well as higher tissue water content and bound water content.So the role of nutrient interception was very apparent for the higher-grafted trees.The result provided physiological anotation to the application of top-grafting in the hardiness cultivation of pear.