Regulation of synthesis and accumulation of osmoprotectants and cations in Beta vulgaris

Abstract

Beta vulgaris accumulates large amounts of sucrose, betaine, and raffinose in tap roots. Regulation of betaine synthesis is important, but its mechanisms are poorly understood. This is partly due to the difficulty of transformation of betaine-accumulating plants. Here, we examined the changes of accumulations of osmoprotectants and cations. One month old Beta vulgaris accumulates betaine 2 - 5 μmol/gFW even under the control conditions. Upon salt stress, the levels of CMO and betaine increased significantly in all the leaves, stems, and roots. The levels of Na⁺ also increased upon the salt stress whereas the levels of K⁺ did not change so much. The suppress expressison of CMO has been examined. The changes of accumulation of sucrose and proline under these conditions will be also presented.