木质化形成的石细胞是影响梨果实品质的重要因素之一，生产中我们发现钙能够部分抑制石细胞的形成。前人研究证明钙信使系统参与了植物生理生化过程及酶活性的调控，本课题组研究证实了0.5%的钙能够抑制梨果实中可溶性和细胞壁结合过氧化物酶的活性，同时木质素合成也有不同程度降低，果实中木质素含量仅为空白对照的65%。此外，通过底物亲和性分析，鉴定出细胞壁结合碱性过氧化物酶可能参与了木质素合成。那么钙是否通过调控此类特定过氧化物酶的转移或活性，抑制了木质素的聚合，实现了对细胞壁中木质素沉积的调控，进而影响梨果实石细胞的形成？本研究拟以石细胞这一影响梨果品质的特殊性状为研究对象，基于我们建立的梨基因组数据库，通过激光共聚焦显微镜结合荧光探针技术、膜片钳技术、分子荧光互补技术等深入剖析钙、过氧化物酶协同调控木质素合成的机制。不仅有助于拓展钙在农业生产中的应用，而且也有助于研发改善梨果实品质的技术措施。

Stone cells, a kind of lignified cells, impact the bad quality to pear fruit, while the calcium can more or less inhibit its formation. Many studies showed that calcium plays important roles in plant metabolism. Our research group found that 0.5% calcium can reduce the activity of soluble and cell wall-bounded peroxidases, along with the reduction of lignin, amounting to only 65% of the control. Besides, analysis of the substrate affinity indicated the involvement of cell wall-bounded basic peroxidase in cell lignification. So, can calcium mediate the special peroxidases? and then inhibit synthesis of lignin? and following with the reduction of stone cells in pear fruit? In order to improve pear quality, basing on our established genome database, the co-regulation mechanism of calcium and peroxidases on lignin synthesis will be studied in this proposal, with the aids of laser scanning confocal fluorescence microscope, patch clamp technique, bimolecular fluorescence complementation and so on. This will be helpful to develop the application of calcium in agricultural practice, and also enhance pear fruit quality.