Australian Grasslands and Adaptation Framework

Present-day, complex communities of rangeland grasses have evolved and dominated much of the Australian continent.

The distinctive characteristics of these rangeland grasses will be revealed by applying the principles and technologies of biogeography, phenotyping, biochemistry, molecular genetics and evolutionary biology, thereby providing new insights into adaptation and traits that can be used to benefit agriculture and society.

Bioplatforms Australia has partnered with key research leaders from Macquarie University, The University of Adelaide, University of Western Australia, Western Sydney University, Royal Botanic Garden Sydney and National Herbaria to provide insights into biomolecular characteristics of traits, photosynthetic biochemistry, seed properties and role in ecological conservation. Application of genomics, proteomics and metabolomics will provide novel insights and opportunities for research and application.

A number of genera have been identified and prioritised for analysis due to their relative distributions across the Australian grasslands. These grassland communities from four common genera have (A) widely contrasting distributions and (B) a diversity of ranges from narrow (e.g. Triodia compacta) to very broad (Themeda triandra). Themeda (kangaroo grass) will act as a model due its broad continental distribution.

As the only grass species that is found across the entire Australian landmass, Kangaroo grass is a unique model to study phenotypic plasticity. An ancestral genome that has enabled adaptation to many environmental extremes (e.g. heat, cold, poor nutrition, high light, biotic stresses) is a unique resource for understanding evolution and the nature of stress tolerance in plants.

Grassland communities are complexes that provide insights into adaptation

• Biogeography – define species’ ranges from existing rangeland distributions. Identify a ‘model set’ by distinguishing species with a very narrow range from others from the same genus with vast distributions such as spinifex
• Ecophysiology and phenotyping – test resilience to extremes of aridity and high-light stress in controlled environments such as that provided by the NCRIS Australian Plant Phenomics Facility
• Biochemistry and proteomics – assess C3 and C4 grasses selected from temperate, savannah and tropical biomes for localised adaptations in the photosynthetic machinery
• Transcriptomics and proteomics – contrast the ‘model set’ (genotypes with varying natural ranges) in a matrix of heat, drought, light regimes to identify gene expression profiles
• Genomics – investigate the importance of allele number (ploidy) in the ‘model set’. In combination with the transcriptomic and proteomic data, identify known stress-response elements and regulatory factors that might play a role in adaptation and stress tolerance
• Bioinformatics – interrogate –omics data for characteristics that might explain the disparate species ranges, especially latitudinal and rainfall gradients
• Seed properties – identify accessions with seed phenotypes that appear to have agronomic potential and applications as a human food source

The success of this project will be built on contributions from a consortium of scholars from universities (including Macquarie, Adelaide, Western Sydney, WA), botanic gardens (e.g. RBG, ANBG, Kings Gardens) seed and pastoral industries (e.g. agri-techs) and public agencies.

Benefits will come from:

• conservation of germplasm in its natural distribution range;
• identification of functional traits and key genes/proteins that confer tolerance to extreme environments and apply them to cereals and pastoral grasses with a view to developing more resilience to aridity, variable fertility and (biotic) stresses from other organisms;
• build stronger connections between existing research agencies such as ARC Centres of Excellence, Linkage programs and CSIRO;
• raising public awareness of the importance of Australia’s rangelands as sources of genes to secure cropping and pastoral systems in increasingly variable climate regimes.