TY - JOUR
T1 - Identification an characterization of QTL underlying whole plant physiology in Arabidopsis taliana: 13C, stomatal conduction and transpiration efficiency
AU - Juenger, T.E.
AU - McKay, J.K.
AU - Hausmann, N.
AU - Keurentjes, J.J.B.
AU - Sen, S.
AU - Stowe, K.A.
AU - Dawson, T.E.
AU - Simms, E.L.
AU - Richards, J.H.
PY - 2005
Y1 - 2005
N2 - Water limitation is one of the most important factors limiting crop productivity world-wide and has likely been an important selective regime influencing the evolution of plant physiology. Understanding the genetic and physiological basis of drought adaptation is therefore important for improving crops as well as for understanding the evolution of wild species. Here, results are presented from quantitative trait loci (QTL) mapping of flowering time (a drought escape mechanism) and carbon stable isotope ratio (¿13C) (a drought-avoidance mechanism) in Arabidopsis thaliana. Whole-genome scans were performed using multiple-QTL models for both additive and epistatic QTL effects. We mapped five QTL affecting flowering time and five QTL affecting ¿13C, but two genomic regions contained QTL with effects on both traits, suggesting a potential pleiotropic relationship. In addition, we observed QTL¿QTL interaction for both traits. Two ¿13C QTL were captured in near-isogenic lines to further characterize their physiological basis. These experiments revealed allelic effects on ¿13C through the upstream trait of stomatal conductance with subsequent consequences for whole plant transpiration efficiency and water loss. Our findings document considerable natural genetic variation in whole-plant, drought resistance physiology of Arabidopsis and highlight the value of quantitative genetic approaches for exploring functional relationships regulating physiology.
AB - Water limitation is one of the most important factors limiting crop productivity world-wide and has likely been an important selective regime influencing the evolution of plant physiology. Understanding the genetic and physiological basis of drought adaptation is therefore important for improving crops as well as for understanding the evolution of wild species. Here, results are presented from quantitative trait loci (QTL) mapping of flowering time (a drought escape mechanism) and carbon stable isotope ratio (¿13C) (a drought-avoidance mechanism) in Arabidopsis thaliana. Whole-genome scans were performed using multiple-QTL models for both additive and epistatic QTL effects. We mapped five QTL affecting flowering time and five QTL affecting ¿13C, but two genomic regions contained QTL with effects on both traits, suggesting a potential pleiotropic relationship. In addition, we observed QTL¿QTL interaction for both traits. Two ¿13C QTL were captured in near-isogenic lines to further characterize their physiological basis. These experiments revealed allelic effects on ¿13C through the upstream trait of stomatal conductance with subsequent consequences for whole plant transpiration efficiency and water loss. Our findings document considerable natural genetic variation in whole-plant, drought resistance physiology of Arabidopsis and highlight the value of quantitative genetic approaches for exploring functional relationships regulating physiology.
KW - carbon-isotope discrimination
KW - water-use efficiency
KW - natural allelic variation
KW - genetic-variation
KW - photosynthetic capacity
KW - polygonum-arenastrum
KW - drought adaptation
KW - tolerance
KW - traits
KW - selection
U2 - 10.1111/j.1365-3040.2004.01313.x
DO - 10.1111/j.1365-3040.2004.01313.x
M3 - Article
VL - 28
SP - 697
EP - 708
JO - Plant, Cell & Environment
JF - Plant, Cell & Environment
SN - 0140-7791
IS - 6
ER -