Salt Secretion in some Chenopodium Species

Abstract

Salt secretion to epidermal bladder hairs was investigated in Chenopodium album L., Ch. giganteum D on and Ch. murale L. after treatment with 100 mmol. I −1 NaCl in culture solution. In all three species, chloride concentration in the vacuole of the bladders exceeds the chloride concentration in the leaf lamina. In Ch. album and Ch. giganteum double mesophyll concentration may be reached in the bladders. Ion accumulation in bladder hairs is usually described by accumulation ratios. This figure does not change in the course of leaf development with respect to chloride. In sodium and potassium, however, it changes with time, probably because of changes in water content of the bladders and changes in ion concentration in mesophyll cells. Therefore, consideration of average accumulation ratios, including older leaves, still with intact bladders, does not necessarily give the real amount of secretion capacity. Salt regulation by bladder hairs of Chenopodium species can be almost neglected because of their minimal volume in relation to the remaining plant tissues. Nevertheless, comparative studies of Chenopodium , and Atriplex bladders can contribute much to the general understanding of this secretion process.