The functional and structural role of phloem in the performance of Cerrado plants

• Grant number: 21/14598-1
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: September 01, 2023
• End date: August 31, 2026
• Field of knowledge: Biological Sciences - Botany - Plant Morphology
• Principal Investigator: Rafael Silva Oliveira
• Grantee: Larissa Chacon Dória
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 19/07773-1 - Restoring neo-tropical dry ecosystems - is plant functional composition the key to success?, AP.TEM

Abstract

The increased extreme drought episodes as a result of the ongoing climate change represents a potentially irreversible threat to plant biodiversity loss. As a result of such changes, mass mortality of plant as well as changes in patterns of leaf phenology have been observed. Thus, there is a need to understand what are the internal biological factors that mediate these two phenomena. The phloem, or inner bark, is a plant tissue that transports non-structural carbohydrates resources and storages water and sugars. Consequently, this tissue has a potential functional link with plant drought responses by its structural and functional link with the xylem, and with leaf phenology by the use of carbohydrate resources for the production of new leaves. Therefore, due to the variety of functions performed by the inner bark, it is essential to put it under a broader context, treating as a modulating tissue of plant-environment interactions, a perspective that goes beyond the common interpretation of protection against fire. Here, we will test the relationships of the (ultra)structure of the inner bark features (and the xylem-inner bark interactions) with the daily variation of plant water potential in Cerrado species. Also, we will test inner bark relationships with the different timing of leaf production/extension at the end of the dry period. This project is part of the FAPESP thematic project (N 19/07773-1) which aims to improve new policies of Cerrado restoration based on a variety of plant functional traits. In addition, this project is part of a national partnership between two research groups of universities from São Paulo state, as well as with an international institution. Therefore, the outputs of this research will be important to understand how the microscopic features of xylem and phloem are ultimately related to responses in the ecological performance of Cerrado species. (AU)