Differentiation of raphide crystal idioblasts in isolated root cultures of Yucca torreyi (Agavaceae)

Abstract

Excised primary roots of Yucca torreyi (L.) were cultured in various media, and development of cortical raphide crystal idioblasts was observed. Idioblasts were consistently produced, required 24 h to differentiate fully from initials in isolated root cultures, and developed normally relative to those cells in intact roots. In vacuoles of idioblast initials, we observed an electron-dense amorphous material associated with paracrystalline bodies and membranous crystal chambers. Crystallization occurs within and is apparently controlled by crystal chamber membranes. After crystal production, crystalloplastids differentiate lobed regions, and cables of tubules and mucilage form within the central vacuole. Many aspects of Yucca idioblast development are common to differentiation of similar cells in intact organs of other plants. Based on our results, we believe that isolated root cultures of Yucca will be useful for future physiological investigations of oxalate metabolism and control of idioblast cytodifferentiation.