Climate Variation and Its Influence on the Cold Tolerance and Phenology Periods of Pear Cultivars in Jilin, China

ABSTRACTThis study primarily analyzed the response of cold tolerance and phenology periods of four pear cultivars to climate differences in central (Gongzhuling) and eastern (Longjing) Jilin, which could provide a theoretical basis for the regional division and cultivation. It showed that there was a significant difference in the cold tolerance of the same cultivars between the two regions. Soluble sugar and soluble starch contents are the most important physiological indicators that determine the cold tolerance of the pear cultivars in Gongzhuling is stronger than that in Longjing. In phenology, only the cessation of terminal shoot extension and growing season length of pear cultivars were significantly related to their contents of soluble sugar and soluble starch. Furthermore, the gray correlation analysis identified the district’s effective accumulated temperature as the key meteorological factors affecting the cessation of terminal shoot extension. The precipitation in the growing season was another major meteorological factor affecting the growing season length. Therefore, in this study, the influence of the main district meteorological factors on the key phenology periods of four pear cultivars, which decided the different accumulation of sugar and starch, eventually lead to the difference in cold tolerance of the same pear cultivar in two regions.