Fuelling the future from the ground up

Alison Gill’s research is helping to feed the world by improving farming techniques in a warming climate.

While evidence of dry farming techniques can be traced back to ancient civilisations, improving our understanding of agricultural methods that limit irrigation usage is becoming increasingly critical as drought severity and frequency increase in many parts of the world.

Dry farming is a method of growing crops without irrigation. The irrigation needs of these crops are typically supplied by rainfall during a wet season, with the crops cultivated during the subsequent dry season. The farming practices used utilise the stored water in the soil.

University of Adelaide alumna and current PhD candidate Alison Gill (B Sc (Adv) 2018, B Sc (Hons) 2019) was the recipient of a Fulbright Scholarship, which allowed her to travel to the University of California, Berkeley in the United States to participate in research on the effect of variety and soil management on the productivity of dry farmed tomatoes. On a 0.5 ha urban field site near the UC Berkeley campus, five varieties of tomatoes were grown without irrigation during the northern hemisphere summer from May to October 2022.

“We selected three indeterminate (tomato) varieties: the current commercial standard, a similar variety which is untested in dry farming settings, and an heirloom with promising performance in water-limited production.

“We also selected two determinate varieties that served as an arbuscular mycorrhizal (AM) fungi model.”

The study considered the following:

• if soil disturbance influenced tomato properties when dry farmed;
• the plant physiology and fruit characteristics of the five dry farmed tomato varieties; and
• the influence of AM fungi on dry farmed tomato productivity.

The study found that on the scale that the practice and field trial was implemented, soil disturbance (such as no-till) may not impact tomato yields or quality, nor affect plant water stress. Tomato variety had a greater influence on fruit properties than soil disturbance, and AM fungi did not impact plants' water stress or result in better fruit yields – although levels of root colonisation were very low.

The research had some tasty outcomes for both gourmands and the local community:

“Although dry farming may reduce yields, it produces tastier, more intensely flavoured fruits that are prized by consumers and chefs.

“The hundreds of kilograms of fruits produced (during the study) were donated to food pantries around Berkeley, which was a great bonus of the research.”

The research that Ali participated in will contribute to addressing the knowledge gap in peer-reviewed dry farming literature, providing options for farmers in water-limited climates or scenarios. It will also form an important part of her PhD thesis.

Ali’s time as a visiting student researcher in UC Berkeley’s Agroecology Lab was an incredible learning experience that expanded her technical and research skills.

“Not only did I gain a wealth of knowledge in agroecology, but I also learned about social justice within Californian farming and land sovereignty.

“The project was particularly special because it allowed me to explore new avenues of interdisciplinary research in collaboration with a diverse group of lab members.”

Ali’s Fulbright Scholarship also provided travel experiences and lifelong memories which will remain with her long after the completion of her nine months abroad.

“One of the most rewarding highlights was the friendships I made with people from the US and other parts of the world.

“I am grateful for the opportunity to have met such wonderful people, many of whom were from my department at the university, within my lab group, or housemates, and I miss them very much.

“I was also fortunate to explore incredible places across the US, especially during a time when COVID restricted travel for many; highlights included visiting nine US National Parks, backpacking in the Sierras, and skiing in Tahoe.”

Closer to home, Ali has been the recipient of the University’s Charles John Everard Scholarship, which is supporting her PhD research on drought stress in industrial hemp crops.

Established from a generous bequest left to the University of Adelaide by Ella Syme Everard in 1972, the Charles John Everard Scholarship is in memory of her late husband. The scholarship continues to support outstanding students to undertake original research in agricultural or horticultural science.

Hemp is an emerging seed and fibre crop in Australia and has been identified as having great potential for sustainable and low irrigation production. Supervised by Professor Rachel Burton, Professor Tim Cavagnaro and Dr Beth Loveys from the School of Agriculture, Food and Wine, Ali’s research is investigating the drought tolerance, water use efficiency, and physiological responses of hemp to water deficit.

Ali’s receipt of the scholarship has been most beneficial to her studies, allowing her to channel all her efforts into her research:

“The Charles John Everard scholarship has allowed me to focus on my PhD without having to worry about casual work to cover living costs.

“The scholarship has taken monetary pressure off and allowed me to focus instead on achieving my best with my research and study; without it, I wouldn’t have been able to devote as much time to my research.

“I am grateful to the donors for their generous contribution to advancing research and study within agriculture.”

Ali’s PhD studies have inspired her to consider a career in research.

“I’m looking forward to finishing my PhD this year and then hope to get a postdoctoral position on the Waite campus.”

Ali is scheduled to complete her PhD studies at the University at the end of 2023. You can keep up to date with the latest findings from Ali’s research by following her Twitter page.