Fruit hardening is a new condition in ‘Suli’ pear fruits that affects their commercial value. This study analyzed the cell wall composition, fruit quality and tissue structure of normal and hardened fruit. The results showed that the protopectin, cellulose and hemicellulose content of hardened fruit were not significantly different from normal fruit. However, in hardened fruit, the soluble pectin content was significantly lower compared to normal fruit, and the lignin content was significantly higher compared to normal fruit, especially in the hardened fruit top region. Hardened fruit also displayed significantly higher cellular lignin autofluorescence than normal fruit. Regarding fruit quality, the firmness and titratable acid content in the hardened fruit were significantly higher than in normal fruit, and the stone cell content in the hardened fruit was significantly higher than in normal fruit, especially in the hardened fruit top region. Fruit water, soluble solid and soluble sugar content in the hardened fruit were significantly lower compared to normal fruit. While observing the development of stone cells, the size and density of stone cells in hardened fruits rapidly increased at 24–34 days after flowering (DAF), especially in the hardened fruit top region. It was likely that a significant synthesis of lignin caused a rapid increase in stone cell density, leading to fruit hardening.

中文翻译：

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硬化梨(Pyrus bretschneideri Rehd)细胞壁组成、果实品质及组织结构的研究

果实硬化是'Suli'梨果实的一种新情况，会影响其商业价值。本研究分析了正常和硬化果实的细胞壁组成、果实品质和组织结构。结果表明，硬化果实的原果胶、纤维素和半纤维素含量与正常果实无显着差异。但在硬化果实中，可溶性果胶含量明显低于正常果实，木质素含量明显高于正常果实，尤其是硬化果实顶部区域。硬化果实还显示出比正常果实显着更高的细胞木质素自发荧光。在果实品质方面，硬化果实的硬度和可滴定酸含量明显高于正常果实，硬化果实中的核细胞含量明显高于正常果实，尤其是硬化果实顶部区域。硬化果实的果实水分、可溶性固形物和可溶性糖含量均显着低于正常果实。在观察石细胞发育的同时，硬化果实中石细胞的大小和密度在开花后（DAF）24-34天迅速增加，特别是在硬化果实顶部区域。木质素的大量合成很可能导致石细胞密度迅速增加，导致果实变硬。在观察石细胞发育的同时，硬化果实中石细胞的大小和密度在开花后（DAF）24-34天迅速增加，特别是在硬化果实顶部区域。木质素的大量合成很可能导致石细胞密度迅速增加，导致果实变硬。在观察石细胞发育的同时，硬化果实中石细胞的大小和密度在开花后（DAF）24-34天迅速增加，特别是在硬化果实顶部区域。木质素的大量合成很可能导致石细胞密度迅速增加，导致果实变硬。