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Trevaskis, B.

Publications and source records attributed to Trevaskis, B..

2 recordsLinked to original sources

OzWheat: a genome-to-phenome platform to resolve complex traits for wheat pre-breeding and research.

For over a century, Australian wheat breeders have successfully adapted wheat to a broad range of climatic conditions and crop management practices. The OzWheat genome-to-phenome (G2P) platform was established to capture this breeding history and explore traits, genes, and their interactions with the environment to enable ongoing research and deliver targets for wheat improvement. A panel of 285 cultivars and landraces were chosen through knowledge of breeding pedigrees to represent both global diversity and the historic flow of genetic variation over more than 100 years of selective breeding in Australia. Genetic characterisation of the panel included identification of genome-wide sequence variants and gene expression profiling across environments. Important traits for adaptation (flowering time and plant height) were assayed in controlled environments and at multiple field sites and years, with genome-wide association analyses (GWAS) using linear mixed models detecting both known and novel loci. Here, we report establishment of the OzWheat G2P platform as a powerful tool to integrate wheat genomes and phenomes and demonstrate its use to identify candidate genes and understand gene by environment interactions. This provides the wheat research and breeding community a new resource to support future cultivar development.

genomics↗

A circadian transcriptional sub-network and EARLY FLOWERING 3 control timing of senescence and grain nutrition in bread wheat

Circadian clocks control daily and seasonal timing of physiology and development. Because of their influence on photoperiodic flowering, variants in circadian clock genes have been selected for phenology during domestication of cereal crops. To explore the potential impact of this genetic variation on circadian-regulated traits, we investigated the relationship of the circadian clock and leaf senescence in hexaploid bread wheat. Phenotyping of a collection of elite wheat cultivars identified significant variation in circadian rhythms which was associated with timing of senescence and nutrient mobilisation efficiency. RNA sequencing revealed substantial reorganisation of the circadian-regulated transcriptome during senescence and a transcriptional sub-network representing a link between the circadian oscillator and regulators of leaf senescence. We used genotypes of multiple circadian clock genes to assign cultivars to chronotypes, which could be used to predict circadian-regulated phenotypes. This identified a deletion variant of EARLY FLOWERING 3-D1 (ELF3-D1) attributed to a phenology locus, Earliness per se (Eps-D1), and we used near-isogenic lines (NILs) to show that it affects timing of senescence and grain protein content (GPC). Thus, there are potential consequences of circadian clock genes selected for phenology on other valuable crop traits.

plant biology↗