Format: ORAL

Dorota Borowska-Wykret1, DorotaKwiatkowska1, Aleksandra Liszka2, Jan Lyczakowski2, Anna Nowak1, Lukasz Wiczolek2, Wiktoria Wodniok1

1 Faculty of Natural Sciences, University of Silesia in Katowice, Poland 2 Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland

Plant tissue is a cellular solid material in which walls of adjacent plant cells form a complex network that is the main mechanical component of the tissue. Therefore, mechanical properties of cell walls are crucial for plant growth and for supportive or movement functions of plant organs. Protoplasts of growing cells are encapsulated in primary cell walls that are under tensile stress generated by turgor. These prestressed walls provide structural support to growing organs but at the same time are a direct growth regulating factor. The regulation acts via mechanical properties of primary walls that depend on their chemical composition and structural anisotropy. Secondary cell walls, in turn, are formed after growth cessation and ensure performance of specific organ functions even long after death of the encapsulated protoplasts. We investigate the complex relationships between cell walls and organ function and growth using trees as a model system. Trees are unique in providing opportunity to investigate both primary and specialized woody secondary walls in the same plant species. In our work we combine biochemical analyses with mechanical tests and deformation measurements. We address the question on how composition of primary cell walls affects elongation of hypocotyls and their stiffness, focusing on the hemicelluloses, which are the least extensively studied component of primary cell walls. We also introduce a scale of conifer (Abies sp.) cones as a new model to study the role of cell wall in movements of organs built of dead cells. Similar, albeit slower, movements are observed in reaction wood, which has major importance for the forestry sector. This research is funded by National Science Centre, Poland, grant No 2022/47/B/NZ3/01972.