中文摘要：

以‘红心7号’和‘红心9号’两个红肉苹果新品系的成熟果实为试材,检测贮藏期间硬度与香气成分及其相关酶活性与基因表达量。‘红心9号’苹果贮藏期间果实硬度极显著低于‘红心7号’,而乙烯释放速率极显著高于‘红心7号’;总香气物质、酯类含量及AAT1、AAT2和LOX基因表达量均极显著高于‘红心7号’,而在贮藏后期（90~120 d）果实醇类与醛类含量及HPL和ADH基因表达量均极显著低于‘红心7号’;PG、XET、PME、AM、α-L-Af和β-Gal等6个果实软化相关基因表达量及其酶活性大都极显著高于‘红心7号’。上述结果表明乙烯释放速率和酯类含量高及酯类生物合成和果实软化相关基因上调表达可能是导致‘红心9号’苹果贮藏期间果实硬度显著低于‘红心7号’的主要原因。香气物质种类、含量及其变化能作为果实贮藏品质评价的指标之一。

英文摘要：

Using 2 red flesh apple strains‘Hongxin 7’and‘Hongxin 9’as experimental materials,we investigated volatile components,firmness,cell wall-modifying enzyme activities and gene expression related to aroma and firmness. The results showed that during fruit storage,the firmness in‘Hongxin 9’was significantly lower than in‘Hongxin 7’while the ethylene production rate in‘Hongxin 9’was significantly higher than in‘Hongxin 7’. The contents of ester and total aroma as well as the expression of AAT1,AAT2,LOX in‘Hongxin 9’were significantly higher than in‘Hongxin 7’during fruit storage,however,in the later period of storage（90–120 d）,the contents of alcohols and aldehydes and the expression of HPL and ADH in‘Hongxin 9’were significantly lower than in‘Hongxin 7’. The cell wall-modifying enzyme activities and related-gene expression of PG,XET,PME,AM,α-L-Af and β-Gal in‘Hongxin 9’were significantly higher than in‘Hongxin 7’during fruit storage. All results indicated that the main reason causing the firmness in‘Hongxin 9’was lower than in‘Hongxin 7’during fruit storage was of a high level in the ethylene production rate and ester content and the up-regulated expression of ester biosynthesis related genes and cell wall related genes. Meanwhile,the change,types,content of aroma compounds can be used as one of the evaluation indicators of fruit quality during storage.