Sclerotinia management for narrow-leaf lupin crops in Western Australian farming systems

⁠⁠⁠Sclerotinia stem rot (SSR) is a serious but sporadic disease of broadleaf field crops in Australia. The main causal organism, Sclerotinia sclerotiorum, has a host range in excess of 400 plant species including all broadleaf crop species within the dryland cropping rotation. In recent years, SSR has become an important disease of narrow leaf lupin (Lupinus angustifolius; NLL) in the Western Region, driven largely by the size of the area sown, frequency of the crop within rotation, frequency of canola within the rotation, and return to more average winter and spring rainfall patterns.

Whilst considerable research efforts have been undertaken for canola, information on impact and management of the disease for other pulse crops, including lupin, remains limited. Observations in the field in recent years suggest that the epidemiology of the disease is different for pulse crop species compared to canola and there is limited information for growers to implement any form of effective management. Therefore, there is the need to improve our understanding of the epidemiology and development of management strategies of SRR in NLL crops.

This investment aims to provide:

•Data on the economic/disease impact from SSR in NLL crops to growers and advisers. This information will provide regionally relevant economic thresholds that represent the loss of profit in the presence of SSR on lupin in the Western Region.

•Better understanding of how cultural practices influence disease development - Pulse crops produce dense canopies due to their growth habit and consequently create micro-environments that are conducive to disease development. Therefore, modifying some cultural practices such as increased row spacing, lower plant densities and altered sowing time have the potential to provide some disease control and or reduce fungicide usage

•Information on the effectiveness and optimum timing of fungicides