Robigalia Roundup LXVIII

Tomato brown rugose fruit virus (ToBRFV) is a positive-sense single-stranded RNA virus in the genus Tobamovirus (family Virgaviridae). It is closely related to Tomato mosaic virus and Tobacco mosaic virus but forms a distinct species.

Tomato and capsicum/chilli are the primary natural crop hosts, with tomato generally the most severely affected. Experimental work shows ToBRFV can infect more than 40 species across several plant families, although non-solanaceous hosts are mainly considered indicator or weed hosts rather than major economic crops. No commercial tomato varieties with complete resistance are currently available, although breeding for improved tolerance and resistance is progressing.

In tomato, foliage symptoms include light–dark green mosaic, leaf narrowing and deformation, and dark green bubbling. Fruits often show yellow blotches, brown to black rugose patches, uneven ripening and deformation, rendering them unmarketable. In capsicum, symptoms include leaf puckering and mottling, plant stunting, and fruit with small yellow to brown rugose spots and necrotic blotches. Severe outbreaks can cause major yield and quality losses, with reports of up to 70% reduction in marketable yield.

ToBRFV was first reported from Israel and Jordan in the mid-2010s and has since spread widely across Europe, the Middle East, Asia, North America and parts of Central and South America. It is now recorded from at least 35 countries and is considered a significant global threat to protected and field tomato production. In Australia, the virus was first detected in 2024 and, following multiple incursions, eradication was declared no longer technically feasible in 2025, with management transitioning to long-term control.

Management relies on exclusion, early detection and strict hygiene, as curative treatments are unavailable. Key measures include sourcing tested seed and seedlings, implementing rigorous on-farm biosecurity (sanitation of tools, hands, clothing and surfaces), controlling volunteer hosts and weeds, and promptly removing infected plants. Resistant or tolerant varieties are emerging but must be integrated with hygiene practices to limit virus introduction and spread.

Scroll down to meet a recent Master’s graduate whose research focused on ToBRFV 👇

This week, I’m happy to introduce Jasmine Sidhu, who has recently completed her Master’s from The University of Tulsa.

Jasmine’s journey in plant pathology began during her Undergraduate Studies at the Punjab Agricultural University. During her undergraduate studies, she conducted several apprenticeships, including one in the Department of Plant breeding and Genetics where she was responsible for collecting phenotypic data by scoring resistant and susceptible phenotypes of Brassica juncea against Mustard aphid (Lipaphis erysimi).

During her Master’s at the University of Tulsa, Jasmine’s thesis research focused on screening tomato cultivars for resistance against tomato viruses such as Tomato brown rugose fruit virus (ToBRFV) and Horse nettle virus A (HNVA). She also characterised viruses from field samples by diagnosing them by sequencing and molecular techniques.

Though her research, Jasmine is particularly proud that she has been able to identify partially tolerant cultivars to the destructive viruses which had been defying existing genetic resistance. She is also excited to be starting in her new role as a field research intern at Corteva agriscience.

Be sure to connect with Jasmine on LinkedIn to keep up with her latest research updates!

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See you next Monday!

P.S. Why Robigalia? The name originates from the Ancient Roman festival dedicated to crop protection. You can read all about the history here: