Descripción del proyecto
Rice production is the main agricultural source of greenhouse gases (i.e., carbon dioxide; CO2, nitrous oxide; N2O and methane; CH4). Scientific evidence suggest that greenhouse gases (GHGs) produced and accumulated in rice paddies (flooded soils) can be vented out to atmosphere through plant tissues. However, information on the plant characteristics influencing such GHGs emission processes is scarce. The mechanisms of GHGs diffusion from rhizosphere to and along the roots and the vent of these GHGs to atmosphere as well as the permeability coefficient of roots to GHGs are largely unknown. This project aims to identify characteristics of rice roots that reduce both the vent of GHGs through plant tissues from soils to atmosphere (through root apoplastic barriers) and the production of GHGs in soils (oxidation of CH4 to CO2). Moreover, this project will study the root permeability to GHGs and the anatomical and chemical characteristics contributing to GHGs diffusion through plants. This project will use a multidisciplinary approach combining state-of-the-art physiological measurements including microsensing technology (for in vivo gas fluxes), gas chromatography, mass spectrometry and microscopy characterization of plant tissues. It is hypothesized that genotypes with tight barriers to radial oxygen loss will have less permeability to GHGs. Moreover, genotypes with no barriers to radial oxygen loss, high number of laterals and an efficient roots system for O2 transport will allow high CH4 oxidation to CO2, thus reducing the venting of this potent GHG to atmosphere. This project will identify root phenotypic differences among rice cultivars and this will serve as a basis for developing high yielding cultivars with desirable traits reducing GHGs emissions from flooded soils.