Tessa on track to increase nitrogen efficiency

The project has an industry partnership with Australian fertiliser company Sonic Essentials and is part of the ARC Training Centre for Green Chemistry in Manufacturing.

Tessa spoke at the Fruit Growers Victoria conference on Thursday, August 22, to outline the necessity of nitrogen in fruit production.

She said the slow release of nitrogen was needed in the industry due to losses incurred by the nitrogen cycle within the soil.

“Approximately 50 per cent of nitrogen is lost to the environment after application,” Tessa said.

“I am looking at developing a novel urea coating to improve the nitrogen use efficiency and the delivery from urea.”

Tessa told Country News that she had worked for Sonic Essentials for three years before pitching the PhD idea to them.

“I said I wanted to work on this, and they said ‘okay, fine’,” she said.

The deal means that for a set number of industry placement hours, the company partially funds Tessa’s project.

“I am extremely lucky to have Sonics support my research,” Tessa said.

“The company also provides extra expertise in the field, they support my attendance to conferences and field trips as well as industry meetings.”

The deal also allows for access to field sites for conducting her experiment trials and ‘plenty of other resources’.

The project entails a full analysis of pellet coating leaching into the soil with pot trials in glasshouses at Monash University followed by field trials at Ardmona.

Although there are similar technologies on the market, Tessa said they had their drawbacks.

“There are plenty of them, but there are downsides to them though — they can build up toxic components in the soil, they can be very expensive and they can be quite ineffective,” she said.

“There are inhibitors they use, so we are focusing on improving nitrogen use through all the stages of the nitrogen cycle.

“I am looking at developing a more optimal, more efficient product.”

In the nitrogen cycle, urea hydrolises (breaks down) to ammonium and then, via nitrification, into nitrate.

“Those two forms will be taken up by the plant at different levels, but they are still both lost, either by emission or leaching.

Tessa said leaching to the groundwater system was a primary concern.

“Also, about 2.1 per cent of greenhouse gas emissions globally are from urea production, in making ammonia,” she said.

“If you can halve the amount of that, then that will make a difference to the climate.”

Despite Tessa’s enthusiasm for sharing knowledge — epitomised in her role as a ‘green chemist’ outreach teacher to primary school children — she keeps the urea coating’s ‘11 secret herbs and spices’ under wraps.

“I can’t tell you what’s in it, nope, and I can’t tell you the precise coating technology as such, but one day it will be on the market and everyone can (then) see how it works,” she said.

“I am really focusing on the novel aspect of it, but also keeping it simple, keeping it cheap, so it’s affordable and really focusing on the grower user.”

Despite being raised in Melbourne, Tessa said her inspiration to enter agricultural science came from weekends spent travelling up to the Southern Riverina to family properties.

“I have always loved agriculture, but I had that science aspect also — I somewhat love chemistry — but I wouldn’t say I am purely off the land,” she said.

“I have a nice mix — a very balanced life, went to school in Melbourne, but weekends on the properties helping out is why I am here: because I loved it up here.

“And then I ended up doing a PhD — I don’t know where that came from.”

Her advice to aspiring young women comes from her satisfaction of having made the right decisions.

“I’m living life, making the most of it with just family, just chilling. I love my travel, love my sport, love my friends,” Tessa said.

“Follow what you love, and if you don’t know what you want to do, it will come.

“There will obviously be rough times, but things will come your way — be open to change: things will come your way.”