Stone cells are among the major factors affecting fruit quality and taste. With the development of social economy, the standards set for the appearance and taste of pear fruit are becoming increasingly demanding. Stone cells are the result of secondary thickening of parenchyma cell walls. Coarse peeled and green head fruits are related to an increase in stone cell content during the production of ‘Korla Fragrant Pear’. Currently, research on pear stone cells mainly focuses on the observation of stone cells, synthesis and polymerization of lignin monomers, and analysis of the lignin structure (Ashajiang et al., 2020). After freezing and separation, the stone cells of pears were observed using an optical microscope and were found to be of different shapes. They were deposited by high levels of lignins and cellulose, and were classified as short stone cells (Li and Zhang, 2011). The results showed that many fine characters of the occidental, Baili, and Shali pears have a small stone cell mass and low density. However, the characteristics of some Baili and Shali pears are in contrast to those of most Qiuzi pears (Aalamusa et al., 1994). The final size of the stone cell mass is determined by early and late development of stone cells, and the developmental progress of the stone cells varies according to the variety (Wang, 2014). The secondary wall is mainly formed after lignin deposition, with lignification of the cell wall being closely related to the stone cells. The thick wall formed by the continuous deposition of secondary walls on the primary walls of the parenchymal cells is comprised of stone cells (Yan et al., 2013). The stone cell content correlated positively with the lignin content. The contents of the pulp lignin and stone cell lignin of Xinjiang pear varieties were the lowest among several pear systems (Tian et al., 2017).
In this study, 10 pollination combinations of Xinjiang pear and ‘Korla Fragrant Pear’ were used to analyze changes in stone cell mass density, stone cell and lignin contents, and three enzyme activities in each developmental period of pollination combinations. The relationship between stone cells, lignin, and enzymes was also explored. This study provides a theoretical basis for improving fruit quality and identifying suitable trees for pollination.
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Tian, L.M., Dong, X.G., Cao, Y.F., Zhang, Y. & Qi, D. 2017 Correlation analysis of lignin in pulp and stone cell mass of pear plants J. Southwest Agr. 30 9 2091 2096
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Wang, Q., Gong, X., Xie, Z., Qi, K., Yuan, K., Jiao, Y.R., Pan, Q., Zhang, S., Shiratake, K. & Tao, S. 2022 Cryptochrome-mediated blue-light signal contributes to lignin biosynthesis in stone cells in pear fruit Plant Sci. 318 111211 https://doi.org/10.1016/j.plantsci.2022.111211
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