Developing Crops with Enhanced Characteristics

GENOME EDITING

Genome editing, also known as gene editing, is a technology that allows us to “amend” a specific gene target within an organism. This method is an alternative to introducing a foreign gene into an organism (an approach known as genetic modification (GM) and allows introduction of a genetic mutation similar to those that occur nature and enable precise re-writing of an existing gene to restore the function of an otherwise unfunctional gene. 

Genome Edited Nicotiana benthamiana with increased branching

 

Genome edited Nicotiana benthamiana for functional analysis of developmental gene

In our program, we utilise the state of art genome editing technologies (i.e., CRIPSR and Prime Editing approach) to study gene functions or to give economically important traits, such as tolerance to osmotic stress and disease resistance, to the plant species of interest. Our team also investigates and work on improving this technology by means of increased editing efficiency and its precision.

Genome edited tomato

CUTICULAR WAX ASSISTED RESPONSE TO DROUGHT STRESS

In Australia, N. benthamiana is naturally distributed in six geographic habitat zones, varying from desert to rainforest. Isolates of the species were gathered from these geographically and climatically different locations providing an exceptional set of resources to investigate plant adaptation to abiotic stress, including drought. By comparing the behaviour of these ecotypes, we show that LAB has a short life cycle, early vigour, and a diminished responsiveness to water scarcity. In contrast, a wild accession from a location, with seasonal drought, has evolved a responsive strategy for growth during water shortage, which includes slowing its growth rate and altering its cuticular wax composition. Altogether, these findings show how plants can respond differently to environmental stresses by balancing their needs between growth and the mobilization of secondary compounds. This provides insights for future crop innovation to overcome the limitation in productivity faced in many parts of the world subject to difficult climate conditions. 

Nicotiana benthamiana ecotypes under drought stress

INSECT-PROOFING PLANTS

Numerous invasive insect pest species have emerged and developed as a threat worldwide and to Australia natural environment and agriculture industries. More than 70% of all agricultural pests are insects belonging to the order Lepidoptera such as Helicoverpa armigera, the cotton bollworm (CBW), or Spodoptera frugiperda, the fall armyworm (FAW).

Lepidopteran insect pest

Several approaches to control crop infestations by lepidopteran insects are commercially available with chemical pesticides remaining the most commonly used so far. Unfortunately, the long-term use of these insecticides has led to the development of resistance. Effective alternative protection strategies must be continuously improved to keep pace with the ever-developing resistance and additional evolving invading species.  

For our collaboration with Corteva agriscience we focus on engineering novel environmentally friendly pest management strategies in plants using RNA interference (RNAi). We successfully developed Trans-Kingdom RNAi methods based on transplastomic dsRNA expression targeting essential genes of the insects. Our goal now is to improve the technology and apply it to other pests. 

Insect-proofing plants – H. armigera bioassay

 

Insect-proofing plants – H. armigera pupae after plant bioassays

HARNESSING THE SECRETS OF RESILIENT PLANTS FOR IMPROVED CROP PERFORMANCE UNDER STRESS

Improved Crop Tolerance 

Drought is the single most greatest cause of crop loss globally. Although replacing traditional and local crops with elite varieties harbouring superior agronomic traits has led to increased yields, it has also caused the gradual erosion of genetic diversity and stress tolerance. For example, domesticated crops designed to grow and yield, die upon small losses of water. On the other hand, wild species grow slowly but have evolved efficient survival mechanisms. One small group of flowering plants, termed resurrection plants, can lose up to 90 % of their water and remain in that state for months until watering. As stress tolerance is genetically coded, resurrection plants and other resilient species may hold the secret to improving crop drought tolerance. As part of an international consortium comprising researchers from the USA, South Africa and Denmark, we have studied the physiological and genetic responses that confer the stress tolerance of resurrection plants. At QUT, we showed that resurrection plants tolerate stress by “eating” toxic molecules within their cells via a pathway known as autophagy (auto = self, phagy = eating). Transfer of a single gene from the resurrection plant into chickpea translated to improved yields under irrigated and simulated drought conditions in glasshouse and field trials. Our next goal is to learn more about the stress response mechanisms of this fascinating group of plants and transfer this knowledge to crops without genetic modification using sophisticated genome editing techniques.  

Isaac Njaci holding Tripogon loliiformis

COMMERCIALISATION OF AUSTRALIAN NATIVE RICE FOR INDIGENOUS ENTERPRISE DEVELOPMENT: AGRONOMY AND VALUE ADDING

This project aims to lay the foundations for commercialisation of Australian native rice as a high-value, low volume, culturally-identified, nutritious food, especially for tourism, gourmet food and restaurant markets, and for value-added products. The involvement of CRC partners, Pudakul Aboriginal Cultural Tours and Olive Vale Pastoral Pty Ltd demonstrates strong support for the project among Australian Indigenous enterprises and communities. Myera, an indigenous enterprise working with the Cree people in Manitoba, Canada, has successfully developed advanced cultivation techniques for Canadian native rice, and supplies both mainstream and niche nutrition product in North America markets. The involvement of Myera adds a first nation collaboration dimension to the project with potential for indigenous bilateral trade partnerships. Myera is also interested in the value-additions to native rice. NT DPIR is making a substantial commitment in facilities and staff, has been conducting rice trials in the NT and has a Research Agronomist with more than 25 years of rice research experience in the Philippines. The university partners have been undertaking research on Australian native rice for over 25 years, including research into the ecology of native Australian rice, cooking trials and market surveys of tourists and restaurants with Pudakul. 

Australian native rice in nature

Seeds of an Australian native rice