Behavior of Calcium Oxalate Crystals with Leaf Development in Rice Seedling

Abstract

Deposition and development of calcium oxalate crystals were observed with the development of coleoptile and several leaves in a japonica rice seedling (cv. Sasanishiki). The results are summarized as follows: 1) Prismatic crystals first deposited in the parenchyma cells of coleoptile when the 2nd leaf emerged (Figs. 1, 2, 3) and then slightly increased their size as aging of seedling proceeded. 2) In leaf blade before emerging from the previous leaf sheath, small crystals deposited in bundle sheath cells, but not in chlorenchyma cells. When the leaf blade began to emerge and unfold, the bundles of crystals abundantly deposited in chlorenchyma cells (Figs. 4, 6, 7) and thereafter they increased size and number per cell with aging of the leaf. The size and number of crystals and thus the volume percentage of them to the cell which contained them tended to be greatest at the upper part and smallest in the basal part of leaf blade (Fig. 9). There was positive correlation between the cell size and the crystal size (Table 1). 3) In leaf sheath the crystals deposited initially in the parenchymatous cells including bundle sheath and then in the chlorenchyma cells (Fig. 8). Their length, width, volume and volume percentage to the cell also increased with aging of the sheath, although their amount was less than in the leaf blade.