CoPIs: Yona Baguma (National Agricultural Research Organization, Uganda) and Henry Wagaba (National Crops Resources Research Institute, Uganda)
Anthropogenic emissions of gaseous nitrogen (N) have become a severe problem worldwide. Although much is known about the alteration of physiology and growth of plants exposed to pollutant gases, most of these studies are observational, from an ecological perspective, and do not address the possibility of using gaseous nitrogen to augment plant growth. If successful, this EAGER project will harness and exploit known molecular mechanisms of uptake and transport of soil N to facilitate these processes for airborne N. The results generated from this exploratory and high risk research may also point the way to similar strategies for N use in other species and for other important gaseous pollutants. This project will foster intellectual and technical exchange in U.S. and Africa in the area of molecular plant physiology to develop novel strategies for "pollutant" utilization in important crop species such as cassava, rice and potato.
Certain air pollutants, including ammonia and nitrogen dioxide, are absorbed by leaves and are potential sources of nitrogen (N) needed for plant growth. However, plants did not evolve to take up these compounds from the air, and even if the nutrients are absorbed they may not be utilized correctly. Indeed, it has been noted primarily by ecophysiologists and forest biologists that these aerial nutrients stimulate shoot growth under certain conditions. However, it is also the case that the newly formed organic compounds are not transported out of the leaves, sequestering not only the absorbed N, but much of the carbon (C) derived from photosynthesis. As a result, root growth is inhibited, leaving the plants susceptible to drought and other stresses. In addition, the edible parts of crop plants, including tubers, do not benefit from nutrients if they stagnate in the leaves. To address this challenge, this EAGER project will develop and test novel molecular strategies for increasing the absorption and transport of aerial-derived nitrogenous compounds in potato, cassava and rice using select candidate genes identified in model plants such as Arabidopsis. All data and resources developed in this project will be available to the public. DNA sequences will be deposited at GenBank.