Temperature response of leaf gas exchanges in C3 and C4 tropical forages

• Grant number: 12/12147-3
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: September 15, 2012
• End date: November 14, 2012
• Field of knowledge: Biological Sciences - Botany - Pant Physiology
• Principal Investigator: Carlos Alberto Martinez y Huaman
• Grantee: Matheus Enrique Bianconi
• Supervisor: Kevin Lee Griffin
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: Columbia University in the City of New York, United States
• Associated to the scholarship: 11/04620-8 - Effects of elevated CO2 and warming on physiology of two contrasting tropical forage species, BP.MS

Abstract

Plant carbon balance results from the interaction among photosynthesis, photorespiration and mitochondrial respiration, and tightly depends on the environmental conditions. It is known that light partially inhibits mitochondrial respiration, and some authors have proposed that this phenomena is associated with photorespiration. In spite of its major significance for the integrative understanding of gas exchanges physiology and ecosystem carbon balance, there are few studies on the quantification of the non-photorespiratory CO2 evolution in the light; in this way, the understanding about photorespiratory influences on the mitochondrial respiration under different environmental conditions is still incipient. As temperature is one of the major environmental constraints to plant physiological functions, great efforts have been made to understand its influence on plant carbon balance, especially within the context of climate change. The main objective of our study is to obtain data about the temperature effects on CO2 exchange in leaves of two tropical forages, Stylosanthes capitata (C3) e Panicum maximum (C4), as a fundamental effort to get a detailed understanding of the results that will be obtained from the MiniFACE-experiment in Brazil (Thematic Project 2008/58057-8, in progress), in which is attached the master's degree project related with this propose. This work will be carry out under Prof. Kevin L. Griffin orientation at the Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA. Prof. Griffin has great experience in this subject and has a distinguished system of temperature control in his laboratory, which was designed to conduct non-destructive analyses of leaf gas exchanges. (AU)