Latest News Archive

Please select Category, Year, and then Month to display items

Rust diseases remain a serious threat to food crops in South Africa

07 August 2025 | Story Martinette Brits | Photo Stephen Collett

Prof Willem Boshoff shares insights from decades of rust disease research during his inaugural lecture at the University of the Free State.

Rust diseases of food crops remain one of agriculture’s most enduring and evolving challenges. In his inaugural lecture on 23 July 2025 at the University of the Free State (UFS), Prof Willem Boshoff shared how these complex pathogens continue to pose a significant threat to South Africa’s staple crops – and why continued research is more critical than ever.

Titled Battling rust diseases of food crops in South Africa, the lecture reflected on decades of rust research and recent developments in pathogen virulence. Prof Boshoff, from the Department of Plant Sciences, emphasised that the threat posed by rust fungi today stems from their “mechanisms of variability, their ease of long-distance spore dispersal, and subsequent foreign race incursions”.

A shifting disease landscape

Rust fungi are biotrophic organisms that cannot be cultured on artificial growth media. This makes rust research a technically demanding field that requires living pathogen collections, seed sources, skilled researchers, and specialised infrastructure. Prof Boshoff noted that for more than 35 years, the UFS has been at the forefront of this work, monitoring rust pathogens on wheat, barley, oats, maize, and sunflower.

While wheat remains the most extensively studied type, recent rust outbreaks across a range of crops point to a worrying trend. A localised outbreak of stem rust on spring wheat in the Western Cape has been linked to race BFGSF, which carries a previously unknown combination of virulence genes affecting both wheat and triticale. In 2021, leaf rust race CNPSK was detected, showing virulence to the highly effective Lr9 resistance gene.

More recently, stripe rust race 142E30A+ – first reported in Zimbabwe – was found in wheat cultivars from the Free State and northern irrigation areas. “Results revealed increased susceptibility of especially spring irrigation wheat cultivars,” Prof Boshoff explained, particularly due to its virulence to the Yr9 and Yr27 resistance genes.

Rust pathogens affecting other crops are also evolving. In maize, only a few lines with mostly stacked resistance gene combinations were effective against all tested isolates. In sunflower, just four of 30 Agricultural Research Council national trial hybrids showed resistance to local rust races.

Building better resistance

A key strategy in rust control lies in identifying and understanding resistance in host plants. This, Prof Boshoff stressed, requires optimised phenotyping systems for both greenhouse and field conditions, along with a solid understanding of available resistance sources. At the UFS, several recent studies have contributed valuable data to both local and international plant breeding programmes.

“Continued local and regional rust research is critical,” he said. “It supports early detection of new races, alerts to producers through updated cultivar responses, and enables efficient breeding strategies and other sustainable methods of rust management.”

The rust programme at the UFS has not only supported varietal release and on-farm risk management, but also strengthened collaboration between plant scientists, industry partners, and international researchers. With South Africa’s strategic location and history of rust surveillance, the programme continues to play a pivotal role in continental and global food security efforts.

About Prof Willem Boshoff

Prof Willem Boshoff is a plant pathologist with a strong background in wheat breeding and rust disease control. He holds four degrees from the University of the Free State, all awarded cum laude: a BScAgric (1994), BScAgric Honours (1995), MScAgric (1997), and PhDAgric (2001). His doctoral research focused on the control of foliar rusts in wheat.

Between 2001 and 2016, he worked as a wheat breeder and contributed to the release of several commercial cultivars. He joined the UFS Department of Plant Sciences in 2017 and has since been actively involved in national and international research projects, capacity development, and advancing disease resistance in food crops.

News Archive

Prof. Letticia Moja a winner in her category

2004-08-17

Prof. Moja a finalist in award
'Every member of staff is important to me'

Michelle Cahill - Bloemnuus

IF you are in need of a dose of inspiration, try and get an appointment with Prof. Letticia Moja, the Dean of the Faculty of Health Science at the University of the Free State. It will not be easy as she has an extremely tight schedule, over and above being a finalist in the 2004 Shoprite/Checkers Woman of the Year competition.

Although not a born and bred Free Stater, this dynamic woman has come to love the Free State. "Once you get past the mindset of a small town and all the negatives surrounding it, it is an absolutely wonderful experience," Moja said.

Moja was born in Pretoria and grew up in Garankuwa as the second eldest of five children. "That was nothing special. I was not the eldest and I wasn't the youngest," she quipped. She had two younger brothers, one of whom died in a car accident and then two sisters.

She went to school in Pretoria and her first contact with the Free State was when she wrote her matric at Moroka High School in Thaba Nchu. "That was one of the best schools for us at that time," she says. After completing matric, she went on to study medicine in KwaZulu-Natal.

In 1982 she returned "home" and completed her internship at the Garankuwa Hospital. Hereafter she specialised in gynaecological obstetrics at Medunsa.

She became the head of the gynaecological obstetrics unit and later opened a branch in Pietersburg.

"This was just about the most heart-rending time of my life. You saw people travelling for up to three days just to see a doctor," she says. "Here we really interacted with the community."

In 2001 she was invited by the University of the Free State to apply for the job of vice-dean of the Faculty of Health Science. "I wasn't too keen," she says, "but they kept on calling to find out if I had applied or not," she says with a smile. "Eventually I gave in and was appointed."

She thought she would work a couple of years under Prof. Kerneels Nel, then the dean of the faculty. "Unfortunately that was not to be. I had hoped that I could learn from him," Moja says.

Prof. Nel died of a heart attack in 2003 after which Moja deputised for him before being appointed as dean.

"This brought along a whole newset of challenges," she says, "Now I have to work out budgets and I need to know what human resources are," she jokes. This has prompted her to take up her studies again and she is currently doing her MBA.

"It has certainly been a challenge to go into management and without my support structure I most certainly wouldn't have been able to do it," Moja says.

Moja is actively involved in her church and serves on various committees including the Health Professional Council where she is acting president of the Medical and Dental Board and the Provincial Aids Council.

To her no job is menial. She recalls when she used to have "high tea" with her staff in Gauteng and Limpopo. "One of the cleaning ladies used to think her job was menial. That is just not so. No hospital can do without even the lowest position. Imagine stepping over rubbish while you're trying to catch a baby. To me everybody is important no matter what you do. "

Moja's eldest daughter is studying for her B.Accounting degree at Wits . Her youngest daughter is in Gr. 9 at Eunice and she has also brought along her niece, who is in Gr. 8 at Eunice. "You see, we need to be three girls in the house."
She feels honoured to have been nominated by the institution especially as it is traditionally male-dominated. "It is not about me, but about the support structure. Nobody can do it on their own. It is a team effort."
BLOEMNUUS - VRYDAG 9 JULIE 2004

Back

Economic and Management Sciences

Education

Health Sciences

The Humanities

Law

Natural and Agricultural Sciences

Theology and Religion

Open Distance Learning

Business School

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept