Plant Cellular Osmotica

Abstract

To cope with the water deficit resulting from saline environment, plant cells accumulate three kinds of osmotica: salts, small organic solutes and hydrophillic, glycine-rich proteins. Salts such as NaCl are cheap and available but has ion toxicity in high concentrations. Small organic solutes are assistant osmotica, their main function is to protect cytoplasmic enzymes from ionic toxicity and maintain the integrity of cellular membranes. Hydrophillic, glycine-rich proteins are the most effective osmotica, they have some characteristics to avoid crystallization even in high concentration, but because they are expensive they are not as commonly used as salts or organic solutes. In addition there is the question of whether the genetic information for growth in saline environment is present in all kinds of plants, both halophytes and nonhalophytes.