Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/10/2006
Publication Date: 10/14/2006
Citation: Xin, Z., Aiken, R. 2006. Variation in Transpiration Efficiency among 400 Randomly Selected Sorghum Accessions[abstract]. The Biology of Transpiration: From Guard Cells to Globe. Snobird, Utah. October 10-14, 2006.
Technical Abstract: Sorghum [Sorghum bicolor (L.) Moench] is a widely-grown cereal grain and a dietary staple for more than 500 million people worldwide. Sorghum is grown primarily in arid and semi-arid regions with no or limited irrigation. Enhanced transpiration efficiency (TE), defined as total biomass produced per unit water transpired, could have a large impact on sorghum yield and yield stability. We developed a mini-lysimetric method that directly measures the whole plant TE in sorghum during vegetative growth (E–V8) under greenhouse conditions. Over 400 sorghum accessions were screened under greenhouse condition at Lubbock, TX and Colby, KS; accessions were randomly selected to represent the origin and working group in the USDA-ARS world collection. Transpiration Efficiency varied 50%, relative to the minimum; many lines exhibited the same trend in TE at both locations; TE was positively correlated with total biomass and root fraction. Instantaneous TE was quantified at the leaf level by gas analysis techniques for 60 accessions with contrasting TE. Leaf internal CO2 concentration was negatively correlated with instantaneous TE, when normalized by vapor pressure deficit (nTE). Leaf nTE was weakly correlated with leaf mass/area ratio and total biomass.