2009 Annual Report
1a.Objectives (from AD-416)
Determine relationships between effects of elevated carbon dioxide on gene expression and physiological responses which increase the response of crop yield to atmospheric and climatic global changes. Determine how changes in carbon dioxide concentration affect the relative competitiveness of crops and weeds. Determine how elevated carbon dioxide affects relationships between fertilizer and weed management practices and crop yield and soil carbon sequestration.
1b.Approach (from AD-416)
Crop and weed species will be grown at the current ambient concentration of carbon dioxide and at 1.5 times that concentration in field plots, using open top chambers, and in growth cabinets. Changes in gene expression, physiology, and the growth of crops will examined at ambient and elevated concentrations of carbon dioxide in combination with high temperature stress, drought stress, and competition from weeds. Soybeans, common beans, spring wheat, oats, and some weed species will be examined for genotypic differences in responsiveness to carbon dioxide concentration. Invasive and non-invasive weed species will be compared for responses to rising atmospheric carbon dioxide. Impacts of elevated carbon dioxide on yield responses to nitrogen fertilizer will be determined in a corn, wheat, and soybean crop rotation system. The effect of elevated carbon dioxide on soil carbon sequestration will be examined in two no-till cropping systems.
It was found that weedy red rice is favored over cultivated rice as carbon dioxide increases. It was found that the macro-climate associated with urban areas, which is similar to projected changes in climate for the mid-21st century, resulted in faster succession and greater influx of invasive plant species. It was determined that growth at elevated carbon dioxide reduced the nitrogen uptake ability of rice partly by decreasing transpiration rate. It was also determined that Arabidopsis is a poor model system for the study of the control of temperature acclimation of photosynthesis because of its very limited acclimation ability compared with crop species. Research with barley showed that carbon dioxide enrichment and a mutation in nitrate acquisition affecting glutamine and total soluble amino acid levels in leaves both notably decreased leaf protein levels.
Variation in seed yield response to elevated carbon dioxide among bean varieties. In order to identify traits useful for adapting crops to rising atmospheric carbon dioxide, the response of seed yield in four different bean varieties to higher levels of carbon dioxide was determined in the field. The variety that yielded best at the current carbon dioxide level did not yield best when carbon dioxide levels were increased. The increase in pod numbers at elevated carbon dioxide was a good predictor of which varieties would yield best at high carbon dioxide. This information will be of use to scientists adapting crops to rising atmospheric carbon dioxide.
Sage, R.F., Coiner, H.A., Way, D.A., Runion, G.B., Prior, S.A., Torbert III, H.A., Sicher, Jr., R.C., Ziska, L.H. 2009. Kudzu [Pueraria montana (Lour.) Merr. Var lobata]: a new source of carbohydrate for bioethanol production. Biomass and Bioenergy. 33:57-61.
George, K., Ziska, L.H., Bunce, J.A., Quebedeaux, B., Hom, J.L., Wolf, J., Teasdale, J.R. 2009. Macroclimate Associated with Urbanization Increases the Rate of Secondary Succession from Fallow Soil. Oecologia. 159:637-647.
Ziska, L.H., Mcclung, A.M. 2008. Differential response of cultivated and weedy (red) rice to recent and projected increases in atmospheric carbon dioxide. Agronomy Journal. 100(5):1259-1263.
Bunce, J.A. 2008. Contrasting responses of seed yield to elevated carbon dioxide under field condition within Phaseolus vulgaris. Agriculture, Ecosystems and Environment. 128:219-224.
Bunce, J.A. 2008. Acclimation of photosynthesis to temperature in Arabidopsis thaliana and Brassica oleracea. Photosynthetica. 46:517-524.
Shimono, H., Bunce, J.A. 2009. Acclimation of Nitrogen Uptake Capacity of Rice to Elevated Atmospheric CO2 Concentration. Annals Of Botany. 103:87-94.