关键词: 枇杷, 种质资源, 成熟果实, 可溶性糖, 聚类分析

Abstract: The aim of this work was to determine the contents and components of soluble sugars in mature fruits of 66 loquat germplasms using the high performance liquid chromatography（HPLC）. The soluble sugars in loquat were comprised of fructose，glucose，sucrose and sorbitol. The content of fructose was the highest with a mean of 39.49 mg ? g-1 FW，and the content of sorbitol was the lowest with a mean of 3.03 mg ? g-1 FW. The variation coefficients of the contents and components of soluble sugars were 29.50%–71.95%，and the sequence was sorbitol > sucrose > glucose > fructose. The content of fructose ranged from 11.01–63.98 mg ? g-1 FW accounting for 19.01%–67.83% in the total sugar. The content of glucose ranged from 5.29–37.53 mg ? g-1 FW accounting for 7.18%–41.63% in the total sugar. The content of sucrose ranged from 1.10–55.92 mg ? g-1 FW accounting for 1.44%–69.72% in the total sugar.The content of sorbitol ranged from 0.64–11.90 mg ? g-1 FW accounting for 0.88%–12.21% in the total sugar. A significant difference of sugar component was found among different cultivars. And the ratios of fructose/glucose，fructose/sucrose and sucrose/glucose ranged from 1.12–3.62，0.27–43.85 and 0.05–8.75，respectively. Based on the UPGMA cluster，66 loquat germplasms could be classified into 2 major types or 5 species groups，which were significantly different among the contents of fructose，glucose and sucrose in mature fruits. Comprehensive analysis on the sugar accumulation modes of loquat germplasm resources could be divided into fructose accumulation-mode，hexose accumulation-mode and sucrose accumulation-mode.

Key words: loquat, genetic resources, mature fruits, soluble sugars, cluster analysis