Correlation and co-localization of QTL for stomatal density, canopy temperature, and productivity with and without drought stress in Setaria. (24th April 2021)

• Record Type: Journal Article
• Authors: Prakash, Parthiban Thathapalli; Banan, Darshi; Paul, Rachel E; Feldman, Maximilian J; Xie, Dan; Freyfogle, Luke; Baxter, Ivan; Leakey, Andrew D B
• Editors: Lawson, Tracy
• Is Part Of: Journal of experimental botany. Volume 72:Number 13(2021)
• Page Start: 5024
• Page End: 5037
• Publication Date: 2021-04-24
• Subjects: Canopy temperature -- drought -- optical tomography -- quantitative trait loci -- Setaria -- stomata; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erab166
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract : This article reports a phenotypic and genetic relationship between two water use-related traits operating at leaf level and canopy level in a C4 model crop species. Abstract: Mechanistic modeling indicates that stomatal conductance could be reduced to improve water use efficiency (WUE) in C4 crops. Genetic variation in stomatal density and canopy temperature was evaluated in the model C4 genus, Setaria . Recombinant inbred lines (RILs) derived from a Setaria italica×Setaria viridis cross were grown with ample or limiting water supply under field conditions in Illinois. An optical profilometer was used to rapidly assess stomatal patterning, and canopy temperature was measured using infrared imaging. Stomatal density and canopy temperature were positively correlated but both were negatively correlated with total above-ground biomass. These trait relationships suggest a likely interaction between stomatal density and the other drivers of water use such as stomatal size and aperture. Multiple quantitative trait loci (QTL) were identified for stomatal density and canopy temperature, including co-located QTL on chromosomes 5 and 9. The direction of the additive effect of these QTL on chromosome 5 and 9 was in accordance with the positive phenotypic relationship between these two traits. This, along with prior experiments, suggests a common genetic architecture between stomatal patterning and WUE in controlled environments with canopy transpiration and productivity in the field, while highlighting the potential of Setaria as a model to understand the physiology and genetics of WUE in C4 species.