Abstract:Plant cell wall is an important three-dimensional dynamic network to support plant growth and protect cells‘ structure. To elucidate the reasons for low breaking-resistance in the low cellulose mutant, the biochemical traits and morphological changes of cell wall were investigate by analyzing physicochemical properties and the ultra-structure of cell wall in the low cellulose mutant [WTBX]LCM527-1[WTBZ] which derived from the rice variety 527(CK) by radiation of 60Co-γ. LCM527-1 appeared obvious fragility in leaf, stem and branches during the whole growing stages and exhibited low break-resistance in the field. In comparison with the wild type 527 (CK), the mutant displayed some changes in the components that involved in assembling the cell wall during five development stages, especially the significant decrease of cellulose. While the content of hemicellulose and lignin was increased. The content of Ca, K, Mn, Na, Si, Zn was all reduced significantly in the rice stem. Ultra-structural features exhibited the different thickness of scler-enchyma and parenchyma of cell walls, which indicated that thinner cell walls and weaker mechanical strength possibly caused by cellulose decreasing, mineral elements reducing and cellular structure deformation. Physicochemical investigation and cellular ultra observation were well displayed the linkage between mechanical strength and chemical components of cell wall.