Evaluation of abiotic stress tolerance in conventional and transgenic wheat and barley

Abiotic stresses such as extreme temperature, low water availability, high light intensity, high salt, and mineral deficiencies or toxicities can severely reduce crop plant productivity. In many cases, several types of abiotic stress challenge crop plants simultaneously. Higher plants have evolved multiple, interconnected strategies that enable them to survive unpredictable environmental fluctuations.

In comparison to model organisms, wheat and barley have the advantages of extensive monitoring and archiving of genotypes and associated phenotypic data and the availability of unique populations adapted to specific environments and end-uses that have resulted from a long history of selective breeding.  These advantages are becoming increasing significant as analytic tools improve.  Application of markers and genomics research in wheat still faces a number of serious issues.  In particular, many of the key traits influencing yield are poorly understood at the physiological level, hard to reliably phenotype and the genetic control is frequently poorly understood.  Results now coming out of genomics studies are providing new insights into stress responses and provide novel strategies to improve stress tolerance. However efficient and reproducible evaluation of phenotypes has become the major limitation in apply these technologies.

In this presentation the methods and protocols used to assess stress tolerance will be outlined.  These include protocols for measuring plant growth rates under drought, salinity and N stress in an automated facility “The Plant Accelerator”, controlled growth conditions under supported hydroponics and soil conditions, plant growth in large bins, where approximately 100 wheat or barley plants can be grown together in controlled environment, semi-controlled field sites where drought and heat stress and a range of N supply regimes can be simulated and field sites for drought, salinity, heat stress and N efficiency use.  These facilities allow analysis of both conventional and transgenic plants.