Dr Zhong-Hua Chen examining wheat under drought
stressint a glasshouse at the University of Western
Sydney – part of a collaborative research project with
the Australian Centre of Plant Functional Genomics
PHOTO: David Wong
As demand in China grows for high-quality malting barley for beer, Australian growers are well placed competitively with established, high-quality malting varieties.
The challenge is to sustain this, with salinity being one of the main weaknesses of modern barley varieties. In drought conditions, when salinity levels increase, barley quality is compromised, rendering it unsuitable for malting.
This is the problem being tackled by young University of Western Sydney research lecturer Dr Zhong-Hua Chen, who is endeavouring to increase salt tolerance in malting barley.
His research, spanning molecular genetics and plant physiology, this year scooped the national Science and Innovation Awards for Young People in Agriculture, Fisheries and Forestry. Dr Chen took out the $22,000 GRDC prize and he also won the night’s overall Agriculture Minister’s prize, worth $33,000, to extend his research.
Dr Chen says the prize money will further his research developing salt-tolerant malting barley in the laboratory, in the glasshouse and then in the field.
He has crossed high-quality Australian malting barleys with salt-tolerant US and Chinese varieties and he is seeking molecular markers and genes conferring salt tolerance. This could lead to new barley lines of good malting quality with improved performance in drier conditions.
“Most malting barley varieties are not tolerant to salt, so you can get good quality and high yield but once salinity and drought strike you lose most of your yield. So we are trying to improve current varieties of Australian malting barley, which are already a very good exporting commodity and make a nice beer.”
Specifically, Dr Chen is analysing the plants’ stomatal guard cells. These stomatal pores are specialised leaf cells that control the flow of carbon dioxide, which the plant uses to make food via photosynthesis. “Water also passes through the stomata for the plant to cool down in very sunny conditions,” he says. “So the stomata are very important and are related to almost all abiotic stresses.”
Dr Chen is looking for plants with better stomata regulation. “These are plants that maintain a reasonably large aperture of stomatal pores under salinity stress, which enables them to continue photosynthesis and keep growing,” he says.
Dr Chen has been collecting stomata images from 10 barley lines and a double-haploid population (100 lines) that have varying salinity tolerance. He is comparing them using software he co-developed during his postdoctoral research in the UK. He aims to identify molecular markers associated with the superior stomatal guard cell traits to develop new salt-tolerant barley varieties with good malting quality.
“I already have in mind a few candidate genes that might be responsible,” he says. “Where a particular barley line has a stronger expression of that gene we will cross it with a current salt-sensitive Australian malting barley variety, and hope to introduce the trait.”
Dr Chen’s project, enlisting the help of his students and in partnership with with his former PhD supervisor, Associate Professor Meixue Zhou from the University of Tasmania, has already made significant progress since it began February. By early next year he hopes to complete a field trial.
While his ultimate career goal is to breed varieties that can survive in high-saline, marginal environments, this research is designed to benefit growers in both current and future growing conditions if a drier climate leads to increased concentration of sodium chloride in the soil.
“One-third of our agricultural land may be significantly affected by salinity in 2050 and therefore breeding malting barley suitable for saline soils is very important to the barley industry,” he says. “When drought kicks in, salinity rises, so if we can get a few good varieties that can tolerate medium to high salinity then we’ll still get reasonable yields.”
This will be crucial for sustaining exports, particularly to Asian countries, including China, where the thirst for beer is growing.
“China is not producing much high-quality malting barley,” he says. “Barley production is high, but most of it is feed quality, so the malting barley market in China is big – and also in other Asian markets such as India and South-East Asia, where there is a growing appetite for beer.”
Dr Chen first came to Australia in 2003 to undertake a PhD at the University of Tasmania. As part of that research he screened more than 70 barley varieties from the US, Australia and China for salt tolerance, finding significant sensitivity in Australian varieties. These findings, he says, helped form the basis of his current research.
During that time, he also honed a strong appreciation for the application of his research – beer. Along with a group of fellow postgraduate students, Dr Chen developed an interest in home brew, creating a variety of styles from light lager to stout. He even entered some samples in competitions: “It was not the best, but not the worst,” he says.
Dr Chen’s partnership with the University of Glasgow and the University of Cambridge involved fundamental science, looking at how the stomata are controlled by stresses including drought and salinity. It was during this period that he helped develop the software that mimics stomata guard cell function and which he is using in his research.
The varied nature of his research experience, covering crop physiology, molecular biology, biophysics and molecular breeding, has led to his project, ‘Functional analysis of stomatal movement genes for barley salt tolerance: connecting gene to performance yield in saline soil’.
Dr Chen says his work reflects a move in research today to become more multidisciplinary. “There is a global trend to get people trained in different areas and to get researchers from different areas to work together,” he says.
“I have been trained extensively in a few different areas and this is an advantage because I can see the connections.”
Retiring GRDC chairman Keith Perrett says Dr Chen’s two awards are recognition of the importance of his work.
“It is estimated that soil salinity accounts for losses of more than $100 million to the grains industry every year,” Mr Perrett says. “Developing crop varieties that yield well in saline soils is one way of overcoming this constraint, so the work being undertaken by Dr Chen is of enormous value.”
Dr Zhong-Hua Chen,
02 4570 1196,
Salt-tolerant wheat now with breeders
Gold for industry stalwart
GRDC Project Code
Overseas, South, North