Is the rhizome hydraulic and nutritionally functional in a Hymenophyllaceae?

Researcher: 
Ferrio Díaz, Juan Pedro
Congress: 
XVI International Colloquium on Plant Ecophysiology
Participation type: 
Comunicación oral
Year: 
2023
Location: 
Parque Katalapi, Puerto Montt, Chile; January 18-20, 2023
Publication: 
Flores-Bavestrello, Alejandra; Escandón, Antonio; Sáez, Patricia; Sancho-Knapik, Domingo; Gil-Pelegrín, Eustaquio; Peguero-Pina, José Javier; Ferrio, Juan Pedro (2023) Is the rhizome hydraulic and nutritionally functional in a Hymenophyllaceae?. XVI International Colloquium on Plant Ecophysiology, Parque Katalapi, Puerto Montt, Chile; January 18-20, 2023

The Hymenophyllaceae are epiphytic ferns with unique traits among vascular plants. Their fronds have only one layer of cells, they lack stomata and they are desiccation tolerant. Previous evidence suggests that rehydration may be faster through the leaves than through the rhizomes. The acquisition of nutrients in this family is unknown. We present results from a water + nitrogen isotope labelling experiment, aimed to determine their water and N source. Fronds and rhizomes from Hymenophyllum tortuosum were inmersed in 1 mg/L N solutions with contrasting isotope composition: H2O + NH4NO3, D2O + 15N-NH4NO3, and D2O + NH415N-NO3. In an atmosphere of 0 kPa VPD, the transport of water from submerged fronds to rhizomes not exposed, and submerged rhizomes to fronds not exposed is the same. Despite the fact that 15N-NH4NO3 presented the greatest labelling in submerged organs, NH415N-NO3 presented the highest intensity of labelling in fronds and rhizomes not exposed. Our results indicated differential ability for uptake and transport of NH4+ and NO3-. The rhizome does contribute to the acquisition of water and nutrients.
Acknowledgments: FONDECYT 2018 Postdoctoral grant N°3180585. Department of Forest Resources at the Agrifood Research and Technology Centre of Aragón (CITA).