Helping plants feed the world

As Earth’s population grows and environmental pressures build, we need to secure food to support billions of people. At La Trobe, a team headed by Professor Jim Whelan is working on plants for sustainable agriculture, aiming to deliver food security and limit hunger-based poverty. The method? Reducing the dependency of crops on phosphate-based fertilisers.

Phosphate is essential to all forms of life. Phosphorus is a component of cells, and plant life provides phosphates to the global food chain and to humans. Phosphate is also a major component of chemical fertilisers used in growing food crops.

After WWII and the subsequent worldwide food shortage, agricultural scientists developed new ways of increasing crop production. The era of chemical fertilisers was born.

Since the 1950s, phosphate has been mined extensively in North Africa, the Middle East and the South Pacific.

But phosphate rock deposits are limited. The South Pacific’s phosphate mines have been exhausted, and some reports predict that production will peak in the next 100 years. Other estimates suggest current deposits will sustain production for much longer, perhaps even hundreds of years. Regardless, this invaluable resource requires our best stewardship to ensure food security for future generations.

But there’s another side to phosphate: while it is essential to life, it can also stifle it.

For over five decades, there has been an excessive use of phosphate fertilisers, making crops more dependent on them. Phosphate is water-soluble, which is how plants absorb it, but overuse causes runoff into streams and rivers – and the oceans.

This runoff pollutes waterways and causes toxic algal blooms that devastate the marine ecosystems by consuming all the dissolved oxygen.

Making plants more efficient

To solve the problem of phosphate, Professor Whelan is leading a project to re-engineer plants. As a result, they’ll be hardier and less dependent on phosphate.

We've made plants "phosphate lazy". We need to find out what we bred out of them and breed it back in.

His team includes around 20 La Trobe researchers, including research scientists, PhD and Honours students.

They’re profiling responses of all plant genes to phosphorus, in whole roots and shoots, or sometimes even in a limited number of specialised cells inside these organs. This painstaking research isolates 50,000 to 100,000 plant cells to identify crucial bottlenecks in phosphate uptake and transport in plant tissues with specialised functions. The aim is to selectively breed the underlying gene variants into elite crops.

'We've made plants “phosphate lazy”,' says Professor Whelan. 'We need to find out what we bred out of them and breed it back in.'

The team is also collaborating with Chinese researchers to improve crops such as rice.
‘In the 70s, China struggled to produce enough food to feed its population, and today China exports food,’ says Professor Whelan.

But there’s a long way to go. Across Asia, tens of millions of people can experience hunger two or three months each year, depending on weather patterns, crop yields and the price of fertiliser.

Food security

Rice is Asia's staple crop and 500 million people globally are rice growers, although this number is rapidly decreasing with increasing urbanisation in developing countries. Rice provides 70% of the calories of the world's people.

Genetic modifications that lead to even small increases in crop yield and disease resistance can have a huge effect on the world's poorest people. The La Trobe team wants to reduce farming costs by 10 to 20 per cent, and to deliver a threefold increase in the phosphate-uptake ability of food-producing plants. This means the lifestyles of poor communities would be improved, and the environment would benefit.

But improving soils and making crops grow better without chemical intervention would benefit all people, rich and poor.

Take Australia, for example. Australia is in the fortunate position of being able to grow enough food to feed the nation now and into the immediate future. But we need to import large amounts of fertiliser to sustain our agriculture.

This adds costs to farmers and consumers, and exposes us to the vagaries of diminishing global phosphate supplies.

Small increments make big gains

Technology and big data have provided a boon for the La Trobe team’s research. Large datasets and predictive modelling have revolutionised traditional studies into plant biology. According to Professor Whelan, people have been working on this for a while.

We've been able to make a major step forward with new technology. It’s opened up a whole new area of processes that people weren’t aware of before.

‘Although it’s not a new topic,’ he says, ‘we’ve been able to identify new regulatory pathways within the plants. We've been able to make a major step forward with new technology. It’s opened up a whole new area of processes that people weren’t aware of before.’

Now, this innovative work is bringing a lot of attention to La Trobe's regional education and agricultural science programs. And it’s forging new paths for the University's collaborative research projects in Australia and overseas.

Professor Whelan loves his work. It allows him to 'provide food security for the world and make a difference on a local as well as international level’. And, as a plant biologist, he can do tests and experiments that would have all sorts of ethical problems if they were performed on animals.

‘In a small time, you can make large steps forward,’ he says. ‘Delivering a 10 to 20 per cent reduction in farming costs represents a small increase in production that might not turn into money. But it might mean a lot to people. When you can feed your family, that’s a big thing, especially for subsistence farming communities.’

In the end, he believes, ‘these things are important for their knock-on effect: sustainable agriculture and sustainable communities, and health benefits for better-nourished people.’

Professor Jim Whelan is in Department of Animal, Plant and Soil Sciences in the School of Life Sciences AgriBio, the La Trobe Centre for AgriBioscience.

See yourself securing the future of food. Explore agricultural sciences at La Trobe.