To provide basic data for studying and evaluating calcium in Prunus humilis, mass fraction and compositional changes of different calcium forms in wild P. humilis seedling types (large fruit and small fruit) and grafted types (top-grafting and low-grafting) were studied by sequential extraction with H20, 1 mol-L"1 NaCl, 20 g'kg"' acetic acid (HAC), and 50 g'kg"1 HC1 during the post-harvest storage process at room temperature. Results showed that in the harvest period the percent extraction of different calcium forms was 98.2%- 99.3% with 70% of the total calcium form being water-soluble calcium and calcium pectate. Calcium pectate content in large fruits was significantly higher (P < 0.01) than in small fruits. Also, water-soluble calcium, calcium phosphate, and calcium oxalate in small fruits were significantly higher than in large fruits (P < 0.01) with the total calcium content in small fruits significantly higher than in large fruits (P < 0.05). Compared to wild seedling types, the extraction ratio of water-soluble calcium for grafted types increased and the extraction ratio of calcium pectate decreased. After post-harvest storage, the composition ratio of water-soluble calcium increased, whereas the ratio of calcium pectate and calcium oxalate decreased; also phosphate calcium and ratios of other forms of calcium did not change. [Ch, 4 fig. 1 tab. 17 ref.]%以野生欧李Prunus humilis为试材,采用不同浸提剂(水,1 mol·L-1氯化钠,20 g·kg-1乙酸,50 g·kg-1盐酸)逐级提取方法,研究了欧李实生类型(大果型和小果型)和嫁接类型(高位嫁接和低位嫁接)果实采后常温储藏过程中不同形态钙的质量分数及组成比率的变化,为欧李钙素研究和质量评价提供基础资料.结果表明:采收期果实中不同形态钙的提取率为98.24％～99.32％,且以水溶钙和果胶钙形态组成为主,约占总钙量的70％左右；大果型果实中果胶钙质量分数显著高于小果型果实(P＜0.01),小果型果实中水溶钙、磷酸钙和草酸钙质量分数显著高于大果型果实(P＜0.01),小果型果实中钙总量显著高于大果型果实(P＜0.05)；与实生类型比较,嫁接类型果实中水溶钙提取率增加,果胶钙提取率下降；采后果实储藏后水溶钙形态组成比率增加,果胶钙和草酸钙形态组成比例下降,磷酸钙和剩余钙形态组成比例无明显改变.
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