NEW research by the NSW Department of Primary Industries (DPI) will focus on the fungal disease Verticillium wilt to help the Australian cotton industry manage the risk associated with the disease.

Cotton plant showing symptoms of Verticillium wilt.

NSW DPI plant pathologist Dr Karen Kirkby and her team, based at the Australian Cotton Research Institute in Narrabri, will collaborate with DPI research scientist Dr Toni Chapman at the Elizabeth Macarthur Agricultural Institute to develop a tool for cotton growers to determine the level of Verticillium dahliae in soil.

Dr Kirkby said Verticillium dahliae was a widespread soil-borne fungal plant pathogen that causes wilt disease on many important crops and trees, including cotton.

“Verticillium wilt is a high-priority disease in the cotton industry biosecurity plan, and when the right environmental conditions occur for the disease it can reduce yields by 30-40 per cent,” she said.

“The Australian cotton industry is worth $2 billion annually to the Australian economy.

“Our aim is to assist cotton growers to implement practices that reduce the impact of Verticillium wilt, assisted by a new tool that can quantify the inoculum levels in the soils.”

Dr Kirkby said the incidence and severity of the Verticillium wilt determined through field surveys, and inoculum levels estimated from soil samples collected at the same time, will be assessed to determine the potential risk to crops.

“New knowledge developed through this project, combined with extensive NSW DPI survey data, will allow the team to use their expertise in cotton pathology to develop decision-making processes that will help growers and managers to assess the risk of where and when to plant cotton,” Dr Kirkby said.

“The key to combating this pathogen will be increasing the understanding of the genetic makeup and how diverse symptoms are in Australian cotton crops.

“The objective of this project is to develop a fast and accurate fee-for-service diagnostic test that will identify the strains of the pathogen that cause Verticillium wilt in cotton. The test will also be capable of estimating the pathogen levels in soil.

“Knowing what strain, and what level of inoculum, is present in a particular field will enable growers and consultants to make informed planting decisions to minimise the risk of yield losses associated with Verticillium wilt.

“The results from this project will also assist other industries that are affected by Verticillium wilt.”

This project is being undertaken as part of the Digital Technologies for Dynamic Management of Disease, Stress and Yield Program, supported by Wine Australia and Cotton Research and Development Corporation, through funding from the Australian Government Department of Agriculture and Water Resources as part of its Rural R&D for Profit programme and NSW DPI.

Source: NSW DPI