Flood of concern over TR4

Two global experts on Panama Tropical Race 4 (TR4) have advised on control measures for North Queensland and warned the upcoming wet season is a danger period.

Professor Altus Viljoen, Chairman of Plant Pathology at South Africa’s Stellenbosch University in South Africa, and Taiwan Banana Research Institute Director and Senior Researcher Dr Chih-Ping Chao visited the TR4-quarantined property and other banana farms in the Tully area in June.
They also addressed the Australian Banana Industry Congress, provided advice to Biosecurity Queensland (BQ), met with Queensland Agriculture Minister Bill Byrne and visited the Queensland Department of Agriculture’s EcoSciences Precinct in Brisbane to speak with banana scientists and see TR4 diagnostic work.
Professor Viljoen, who has worked globally on TR4, said the upcoming North Queensland wet season would be a time of concern for the response and monitoring should continue.
“What is worrying me about North Queensland is the flooding that might take place from time to time there,” Professor Viljoen said. “Water is a major carrier of this fungus.”
There was good potential to contain TR4 in North Queensland.
“I know you can actually stop it where it is right now. It is important to monitor this outbreak for at least a year and a half and also monitor other farms in the area but it can be done,” Professor Viljoen said.
Dr Chao said Australia had an excellent biosecurity record.
“I think if you can be consistent on doing this sort of quarantine and emphasise more of this sort of awareness, I do believe the impact of this disease will be much, much slower compared with the situation in other countries,” he said.
Racing away in Africa
The swift spread of Panama Tropical Race 4 through a farm in Mozambique in Africa was a warning on how fast the disease could spread when unchecked.
Professor Altus Viljoen, said infection rates climbed to between 10,000 and 15,000 plants a week on the farm where there was inadequate containment.
In two years, infestations on one 314-hectare section increased from 5,597 plants to 281,316 – 49.8 per cent of all plants.
“This is when you neglect to treat or contain something. This is why I want to tell you in Australia, I don’t want to scare you but take this serious,” Professor Viljoen said at the Congress.
“When you detect early you can do something about that but once it gets out of hand, you can manage it – but you don’t want to manage it in Africa and you don’t want to manage it in North Queensland at this stage.”
Contributors to TR4 spread included not adequately isolating infested plants, mud draining out of paddocks, infested run-off being used for irrigation, vehicles dropping clods of soil throughout plantations, inadequate wash downs and fencing and unrestricted farm access.
Good groundwork
Research into using soil health to suppress TR4 could help North Queensland’s efforts, the Taiwan Banana Research Institute’s (TBRI’s) Dr Chih-Ping Chao said.
Speaking at the Congress, Dr Chao said important research included work by the Queensland Department of Agriculture’s Dr Tony Pattison.  Suppression methods included using beneficial organisms, ground covers and organic matter and managing soil pH and calcium levels.
“I believe with this sort of R&D, the impact of this devastating disease in your country could be mitigated,” Dr Chao said.
Dr Chao said plant breeding to find TR4 resistant varieties was crucial for the future of banana growing in Taiwan where TR4 was widespread and there was no additional land for farming.
“Unfortunately, we don’t have land such as yours, to spread out. It forced us to think about management,” he said.
Some TBRI plants bred for TR4 resistance have already been trialed by Australian growers.