Phil Thomas: Seeking the microbial edge in hydroponic tomatoes

When Phil Thomas decided he needed a change of career after 30 years as an IT professional, he tentatively chose to study a single online unit on microbiology through University of New England (UNE). The decision changed his life.

Several years after getting hooked on understanding Earth’s most dominant form of life, Phil has moved from Sydney to Armidale and is working full-time on a Masters thesis that seeks to shed light on the little-understood world of microbiology in the roots of hydroponic plants.

His project is funded by Future Food Systems Cooperative Research Centre (CRC), and is being conducted in partnership with Western Sydney University and one of the biggest glasshouse operations in the Southern Hemisphere, the Costa Group’s Guyra Tomato Exchange.

Root microbiology is known to be a vital factor in plant health – good and bad – when crops are grown in soils, but far less attention has been paid to root microbiology in hydroponically grown plants.

Phil’s project focuses on the root microbiome of hydroponic tomato plants. He wants to establish what’s there, how it is affected by plant management, and how it in turn contributes to plant health and productivity.

“The project results will hopefully help Costa to better manage the microbial health of their crops in ways that improves fruit quality, reduces the need for chemical use, and ensures more efficient use of water and fertilisers,” Phil says.

Costa Group’s vast Tomato Exchange glasshouse complex in Guyra, NSW.

Glasshouse hydroponic horticulture is growing exponentially as a technology for producing consistently high quality food with minimal water and chemical inputs.

At its Tomato Exchange, Costa routinely applies probiotic supplements of beneficial microbes to the root microbiome, the rhizobiome, to counter potential pathogens. The supplement contains common soil fungi widely used for biocontrol and plant growth promotion across a range of crops.

However, the efficacy of probiotic supplements varies widely, with results dependent on variable factors like the crop variety and growing medium. Costa has found it difficult to establish when, and to what degree, the supplements are working.

“If we can get a more informed understanding of the effect of bioinoculation on plants, it will help Costa make better-informed decisions about how we use probiotic supplements in future,” says Costa Senior Grower Manager, Tal Kanety.

“Greater understanding of the role of the plant microbiome in soilless horticulture may suggest new methods to improve yield and mitigate the risk of heat and water stress. In the future, probiotics may play an important role in improving general crop health and further reducing the use of chemicals and fungicides.”

Phil’s Masters degree is being conducted under the supervision of UNE microbiologist Dr Gal Winter, soil microbiologists Dr Oliver Knox (UNE) and Professor Jeff Powell (WSU) and UNE agronomist Professor Brian Sindel.

Phil Thomas will be exploring the rhizobiome of greenhouse-grown hydroponic tomatoes for Costa Group under the supervision of UNE’s Dr Gal Winter. Credit: Matt Cawood, UNE

From IT to microbes

Phil Thomas, scientist, is now a long way from the jaded IT tech who spent his days handling alarms from communications equipment.

When he undertook his Bachelor of Science through UNE’s online program, he did so with the aim of developing knowledge “that couldn’t be picked up from five minutes on Wikipedia, and was engrossing enough to be both a career and a hobby”.

Science is a vast field, but after the first few lectures on cell biology and microorganisms “really blew my mind”, Phil knew where his direction lay. Further study confirmed that microbiology is a fascinating, important and inexhaustible subject. He decided to build a new career around it.

Phil’s Masters degree provided the impetus to leave Sydney and move to Armidale with his wife. They bought a motel, which Phil helps run part-time while researching full-time. “I try to be organised, and occasionally succeed. If I didn’t love the study it wouldn’t work.”

Tomato Exchange hopes the UNE research team, including Thomas, can help them find effective ways to optimise the root microbiomes of hydroponically-grown tomato plants. Credit: Costa Group

Day by day, science advances understanding of the microbial world, and each advance shows that this once-hidden world holds a vast influence over the visible world.

“Microbiomes touch on almost all aspects of life, from health and medicine to agriculture, ecology and conservation, and even climate change,” says Phil.

“But microbiomes are mind-bogglingly complex, and very challenging to study. To predict their effects, or develop methods to manipulate them for our benefit, we need to understand the ecology of the microorganisms that inhabit the microbiome – how they interact with each other, with their environment, and, in most cases, with their host.”

“Until quite recently it was difficult to get even a small glimpse of microbial ecology, but advances in molecular technology and computational methods have vastly expanded our capability to make sense of the myriad of interactions between thousands of species that make up the microbiome. I want to help advance the frontier of human knowledge in a field where a little new understanding can lead to big benefits.”

“What else would you want to study?”

Source: Seeking the microbial edge in hydroponic tomatoes I University of New England. Republished courtesy of Matt Cawood, UNE Media

Further reading

For more about the project, check out the CRC’s News story.