Abstract
Anhydrobiotes, which have a high degree of desiccation tolerance, form a glassy state during extreme desiccation. Vitrification has previously been found in cultured plant cells treated with sucrose-enriched medium in a dry state. We have found that desiccation tolerance of Marchantia polymorpha cells is increased by preculture in a medium containing 0.5 M sucrose. However, it was difficult to induce the same high degree of desiccation tolerance in Arabidopsis thaliana cells by the same method. Using cultured M. polymorpha and A. thaliana cells, we examined the exact relationship of desiccation tolerance to glass formation. Thermal analysis by differential scanning calorimetry (DSC) showed that the glass transition temperature (Tg) in M. polymorpha precultured cells was higher than that in A. thaliana precultured cells at the same water content. A. thaliana precultured cells were vitrified easily but did not survive in this severe condition. The results suggested that precultured plant cells are easily vitrified at ambient temperatures after desiccation. For the development of desiccation tolerance in cultured plant cells, it is important to protect the cells against damage caused by dehydration before vitrification.
