Fungus threatening avocados

A Queensland researcher has uncovered a pathogen that could have a devastating impact on the $180 million avocado industry.

Dr Liz Dann, a plant pathologist at UQ’s Queensland Alliance for Food and Agriculture (QAAFI), has identified the pathogen Calonectria ilicicola and offered recommendations for testing and planting that could prevent major damage to avocado crops.

By identifying the fungus and confirming its pathogen status, Dr Dann has ensured that avocado producers and growers can be on the lookout for the disease, which causes severe root problems in young trees.

Calonectria ilicicola is already known to cause black root disease in peanuts and collar rot in papaya, but until now had not been identified as a problem for avocados.

“The use of clean planting material is the most critical step in successful prevention of black root rot disease, caused by Calonectri ilicicola, in avocado,” Dr Dann said.

“The avocado industry has had a scheme in place to ensure clean (disease-free) planting material for many years, and it has served the industry well,” she explained. “By confirming the pathogen status of Calonectria ilicicola with this research, the fungus can be added to the list of identified root pathogens.”

The QAAFI study was published in the Plant Pathology journal.