Recent advancements in plant aquaphotomics – Towards understanding of “drying without dying” phenomenon and its implications

Abstract

The research team of Kobe University’s Graduate School of Agriculture Science, led by Professor Dr Roumiana Tsenkova and a research group from Agrobioinstitute in Sofia, Bulgaria led by Professor Dr Dimitar Djilianov, recently made a significant step forward in understanding the “drying without dying” phenomenon in resurrection plants – a small group of plant species which are able to survive long periods without water. Using aquaphotomics and near infrared spectroscopy, the entire process of desiccation and subsequent rehydration in one such plant – Haberlea rhodopensis was monitored non-destructively and compared with botanically similar, non-resurrection species Deinostigma eberhardtii. The research found that during drying, resurrection plant performs controlled, organized restructuring of water molecular network in its leaves as a preparation for full desiccation which is characterized by accumulation of water molecular dimers and water molecules with four hydrogen bonds, while free water molecules are drastically diminished. This regulation of water structure in the leaves appears to be the protective mechanism against dehydration-induced damages of the tissues which ensures survival in the absence of water. The discovery that water molecular structure is important for preservation of plant tissues not only opens up new possibilities for bioengineering of crops better adapted to combat climate changes but may also have important implications for food preservation industry, preservation of tissues in medicine and in biomedical applications.