Wednesday, November 15, 2006 - 8:45 AM
229-3
Gas Exchange Properties of Agronomic Crops: A Medley of Experimental Methodology and Results after 25 Years.
Alterations in biotic (i.e., water, nitrogen) and abiotic (i.e., light, temperature, [CO2], [O3]) conditions can significantly affect gas exchange properties of agronomic crops. Our objective was to elucidate mechanistic-based ecophysiological response of a broad range of agronomic crops to global change. Pursuant to this aim we implemented a consistent experimental protocol across a multitude of species and functional types. Reported herein we have characterized and quantified the gas exchange properties (i.e., CO2, H2O) of agronomic crops over the past 25-years in open-field (OF), Soil-Plant-Atmosphere-Research (SPAR), Free-air CO2 enrichment (FACE), and open-top-chamber (OTC) technologies. Experimental results discussed include one on citrus (sour orange tree, Citrus aurantium 1987-05), three on fiber (cotton, Gossypium hirsutum L. 1989-91), eleven on grain (wheat, Triticum aestivum L. 1982-84, 1992-94, 1995-97; barley, Hordeum vulgare L. 1993-94; sorghum, Sorghum bicolor L. Moench 1998-99; corn, Zea maize 2002-04), and four on oil/meal (soybean, Glycine max 1983-85, 2002-04) crops. This medley of crops constitutes a broad range of species and functional types for the following comparative studies: monocot (corn, barley, wheat) vs. dicot (soybeans); cool- (temperate zone) (wheat, barley) vs. warm-season (tropical zone) (corn, sorghum) grasses; herbaceous annuals (barley, corn, sorghum, wheat, soybeans) vs. woody perennials (sour orange tree, cotton); photosynthetic pathways of C3 (barley, corn, sour orange tree, soybeans, wheat) vs. C4 (corn, sorghum). These studies have enhanced our understanding of the response of agronomic crops to global change.
Recorded presentation