Genomic Analysis of Plant Water Use Efficiency

Boyce Thompson Institute Plant Research, Ithaca NY

Investigators

Abstract

Water use efficiency (WUE)is among the most fundamental constraints molding the evolution of terrestrial plant cellular anatomy, tissue structure, physiology, and whole-plant morphology. Due to extensive physiological control, modern plants of both natural and agricultural systems have a tremendous capacity to maintain high rates of growth and productivity over a wide range of often challenging environmental conditions.Nonetheless, water utilization and the WUE of growth remain the single most important determinants of terrestrial productivity in both natural and managed ecosystems. Genes that act, singly and in concert, to regulate the development and plasticity of essential plant traits controlling WUE will be characterized. WUE is defined as the ratio of carbon gain in photosynthesis (A) to the associated water loss (E). A genomic analysis of WUE will be undertaken in two crop plants, rice and tomato. Stable mapping populations already available will be the basis of the first screen in whole-genome QTL analyses of rice and tomato. Phenotypic measurements, both physiological and morphological, will be made on contrasting phenotypes at several stages.Fine-mapping efforts will focus on QTLs that condition the most interesting phenotypes. These activities will enhance understanding of the integration of plant water relations and carbon metabolism, develop the most detailed maps of WUE genes and comparative maps across multiple species, and provide new molecular markers to greatly enhance breeding programs for improved WUE.