High-Throughput Analysis Pipeline for Achieving Simple Low-Copy Wheat and Barley Transgenics

Abstract

Transgenic (or genetically modified—GM) plant breeding is increasingly being used as a supplementary tool to many classical plant-breeding programs. Currently the range of transgenic traits accepted for commercial use is largely restricted to herbicide and pest resistance. Given the fact that transgenics can offer an alternative and novel source of genetic variation, pre-breeding research is now increasingly exploiting this technology to tackle a greater spectrum of traits. These traits range from abiotic stress tolerance to improved product quality and nutritional characteristics. Likewise there is an increasing demand for high-throughput methodologies for transgenic plant generation, characterization and phenotyping. Selecting simple low-copy number transgenic events that are both heritable and stably expressed “in planta” is considered a prerequisite to systematic phenotyping for traits of interest. Furthermore, this assessment relies heavily on comparisons to appropriate control plants, in the case of wheat and barley transgenics this is both wild-type and null siblings. This chapter presents a general scheme on which to base selection of transgenics and respective null siblings using wheat and barley as an example. This scheme can be adapted to other similar crop species. Overall this strategy reduces the total number of plants to be genotyped and phenotyped at each generational step, and therefore resulting in significant savings in time, effort, and resources.