Water-Use Efficiency in Crop Production

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. University of California Press and American Institute of Biological Sciences are collaborating with JSTOR to digitize, preserve and extend access to BioScience.

Limits to maize productivity in Western Corn-Belt: A simulation analysis for fully irrigated and rainfed conditions

“…The boundary TE S for grain yield estimated here is well above reported values for winter cereals (20-22 kg grain ha −1 mm −1 ; Passioura, 2006, Sadras andAngus, 2006), grain legumes (12-20 kg grain ha −1 mm −1 ; Loss et al, 1997;Zhang et al, 2000), and oilseed crops (8-13 kg grain ha −1 mm −1 ; Specht et al, 1986;Hocking et al, 1997;Grassini et al, 2009;Dardanelli et al, 1991), which, like our maize estimates, are based on grain yields at standard commercial moisture content for each crop. Except for cases when severe water stress occurs during the sensitive anthesis-silking window (which determines maize kernel number), maize TE S for grain yield is expected to be greater than that for other crops because maize carbon fixation occurs via the C 4 pathway and the energetic cost of its grain is smaller compared to protein-rich legume seed or oilseed crops (Sinclair et al, 1984;Loomis and Connor, 1992).…”

“…The first approach, namely water productivity (WP), provides a benchmark to help farmers set target yields and identify other yield reducing-factors, such as nutrients, pests, and diseases (Passioura, 2006). The second approach based on ET C , namely water-use efficiency (WUE), provides a physiological frontier for water-limited productivity in which the slope represents the seasonal transpiration-efficiency (TE S ) and the x-intercept gives a rough estimate of seasonal soil evaporation (Sinclair et al, 1984). Despite the large number of reported yield/water supply relationships reported for maize, we were not able to find any explicit attempt to define maximum boundary functions for water productivity or water-use efficiency.…”

Intensification of agriculture in the south-eastern Pampas

“…To improve WUE at the crop level several options have been proposed including increasing harvest index, proportion of transpired water and alteration of cropping environment to lower vapour pressure deficit (Sinclair et al, 1984). In our environment, the more adequate strategy to further increase productivity of water on an annual basis should be based on improved capture of radiation by crops.…”

Water use efficiency of marandu palisadegrass as affected by nitrogen and sulphur rates

“…Water use efficiency is defined as crop yield per unit of water consumed or, in biological terms, as the carbohydrate formed in photosynthesis by CO 2 assimilation, solar light and amount of water transpired (SINCLAIR; TANNER; BENNETT, 1984). Water consumption and water use efficiency by crops depend on soil physical conditions, atmospheric conditions and plant characteristics.…”