This project is investigating the environmental conditions that drive tan spot and ray blight outbreaks in pyrethrum.

The challenge

Tan spot and ray blight diseases represent a major risk to yield and the industry’s ability to consistently meet market production requirements. Tackling these issues places a financial and environmental burden on growers and a low-cost solution is needed.

Meet Justin

Justin Shephard and his family have grown pyrethrum in Tasmania for 30 years. He’s acutely aware of the need for an industry-wide program to tackle tan spot and ray blight. “Quite simply, this research, past and future, is very important to the industry,” says Justin. “If we don’t continue to support this form of research, won’t have the industry and pyrethrum as a cropping option”.

Justin’s frank admission highlights the importance of this investment and the urgent need to find low-cost solutions to the industry’s pest problem. “Fungicides are required to manage ray blight and tan spot so we can maximise yield potential and yield gain, particularly in high-disease-pressure years like last year. High disease pressure leads to large yield losses of 30 per cent or more, making the crop return low and not worth growing.”

Justin believes that this research is the key to effective pathogen control and a more profitable, productive pyrethrum industry in Australia. “Without research, we won’t have the disease control we need, and disease control is the biggest yield influencing factor associated with growing the crop.”

The approach

A range of research activities are being undertaken and their results will be used to develop models that identify the relative risks associated with cropping regions and seasons. This information will be used to create a framework for industry decisions regarding the frequency and timing of fungicide applications in pyrethrum.

The impact

The project team will collect field data throughout the growing season, looking at the effects of climate on the diseases, regional differences in diseases, and the relationships between disease pressure and yield loss.

This approach will ensure that high-risk regions are given adequate protection from disease losses and will lead to an overall reduction in control costs for the industry by reducing fungicide sprays in low-risk regions and seasons.

The data obtained throughout the program will eventually be combined to develop disease risk models for the impact of tan spot and ray blight on pyrethrum yield.