desiccationtolerant

Desiccation tolerance is the ability of an organism to survive extreme drying by reducing or suspending metabolic activity and then recovering after rehydration. Organisms with this trait are often called desiccation-tolerant or anhydrobiotes. It is found in a diverse range of life, including certain plants, fungi, invertebrates, and microbes, and is particularly well known in seeds and spores that endure dry periods.

Mechanisms involve accumulation of protective solutes such as trehalose, proline, and other sugars; late embryogenesis abundant (LEA) proteins; antioxidants and molecular chaperones; and cellular strategies like vitrification or glass formation that stabilize macromolecules in the dry state. Damage repair pathways are activated upon rehydration. In seeds, desiccation tolerance is developmentally programmed; in animals and plants, it can be inducible in response to drought stress.

Representative desiccation-tolerant organisms include resurrection plants (for example Myrothamnus flabellifolius, Xerophyta viscosa, and species of Selaginella), mosses and lichens, tardigrades, rotifers, and some nematodes. Some microorganisms form spores or cysts that resist dehydration. Not all species in these groups are desiccation-tolerant; tolerance varies with life stage and habitat.

Ecologically, desiccation tolerance enables persistence in intermittent or unpredictable moisture regimes, contributes to seed banks, and influences biogeography. It often coexists with other stress tolerances, such as tolerance to high salinity or radiation, in cryptobiotic strategies. Research explores its evolution, genetic regulation, and potential applications in crop protection and preservation technologies.