Identification and management of a fungal disease complex in melons (VM22001)
What's it all about?
This investment is improving the melon industry’s capability to reduce the impacts of soilborne fungal diseases through improved knowledge and access to better management practices. The goal is to reduce crop losses by adopting improved and effective soilborne disease mitigation and management strategies.
The research will ensure the Australian melon industry is well-informed with accurate and current data on the pathogens present, their relative importance, geographical distribution, the sources of the pathogens and the conditions that promote disease development.
The research team is evaluating current management practices with a focus on understanding the diversity of fungal pathogens affecting Australian melon crops, where these pathogens survive in the absence of crop hosts and how to reduce this source, abiotic triggers for disease expression to better predict or circumvent these disease outbreaks, the potential emergence of fungicide resistance to some pathogens and new crop genetics for pathogen resistance/tolerance.
The research team work closely with melon growers, seed companies, nursery suppliers and chemical companies to review pathogen spread pathways from seed to field production and identify critical points for intervention to reduce or eliminate pathogen spread.
In the first six months of the project, progress was made across commercial crop surveys, reliable diagnostics, review of plant supply chains, and previous research on disease management and epidemiology.
Commercial crop surveys were conducted in February 2023 in Chinchilla and Bundaberg, Queensland, and Griffith, New South Wales, covering six properties with multiple blocks. The surveys mostly focused on watermelon crops, with two rockmelon crops surveyed in Bundaberg. Disease incidence and crop losses ranged from <1 per cent to almost 100 per cent.
Multiple soilborne fungal diseases were identified in the surveys, including:
- Fusarium oxysporum
- Stagonosporopsis sp.
- Pythium sp.
- Macrophomina phaseolina
Isolates of these pathogens were stored for future use in field trials, bioassays, and in vitro trials. Discussions were held with a major nursery supplier to evaluate the risk of Stagonosporopsis sp. in seeds and its relative infection rate of subsequent seedlings.
A review of published literature confirmed that gummy stem blight, fusarium wilt, and charcoal rot can all be seedborne. No exotic pathogens were detected in the samples.
This project is a strategic levy investment in the Hort Innovation Melon Fund