Research findings to aid growers in combating the disease sclerotinia stem rot in lupins will be delivered at Western Australia’s annual grains research conference next week.
Department of Primary Industries and Regional Development (DPIRD) research scientist Ciara Beard said WA lupin growers were facing increasing pressure from sclerotinia, with disease prevalence rising in recent years.
She will present key outcomes from four years of laboratory, glasshouse and field trials by DPIRD, in conjunction with the Centre for Crop and Disease Management, Mingenew Irwin Group and lupin growers, at the 2025 GRDC Grains Research Update in Perth.
The research has co-investment from the Grains Research and Development Corporation (GRDC).
“This extensive work from 2021-2024 has given us a better understanding of the distribution and impact of sclerotinia, the infection process and how to respond to crop infection,” Ms Beard said.
“There are two types of sclerotinia infection in narrowleaf lupins. The canopy infection which primarily targets the main spike pods, can cause up to 25 per cent yield loss.
“Basal infection, affecting the plant stem at ground level, is potentially more damaging but occurs sporadically.
“It’s important for growers to identify which of their paddocks or crops are high risk and how to respond.
“An effective integrated disease management strategy for sclerotinia canopy infection has been developed, which includes agronomic, cultural and chemical options.
“Strategies for high-risk situations include delaying sowing, wider row spacing, lower seed rates and applying a registered foliar fungicide from full flower to early pod emergence on the main spike.
“Employing a disease management strategy is more likely to be required and profitable in high risk scenarios, which are outlined in the online publication Lupin sclerotinia disease risk assessment guide.”
Research shows management is more economically viable in the medium-high rainfall zones of the Geraldton port zone, followed by the Kwinana port zone.
In contrast, the Albany port zone had insufficient disease incidence from 2021-24, resulting in few significant responses to management.
Ms Beard said effective options for reducing basal sclerotinia infection were currently limited, as foliar fungicide applied during crop flowering is often ineffective.
“Basal infection can cause significant yield loss on infected plants, so ongoing research is crucial to identify the exact drivers of this disease pathway and explore potential management strategies,” she said.
“Reducing seed rate may be a viable option to reduce basal infection incidence for high-risk paddocks or specific areas within paddocks.”
The 2025 GRDC Grains Research Update will be held in Perth on 24 and 25 February.
