Program 5: Integrated management strategies fr Net Form Net Blotch in low, medium and high rainfall zones

Net form net blotch (NFNB) is an important foliar fungal disease of barley that decreases grower profitability by impacting yield and quality. Yield losses in susceptible varieties can range from 18-31%. Generally, less prevalent than Spot form net blotch (SFNB) over the last decade, NFNB is becoming increasingly common since the widespread cultivation of susceptible varieties. Detailed information on yield losses across barley growing regions along with integrated disease management strategies are available for SFNB. However, such detailed information is lacking for NFNB. There is a need to better understand the yield impact of NFNB and to develop improved cultural practices to mitigate its impact. Growers need information on the potential yield losses of different varieties in different environments including the HRZ, MRZ and LRZ to determine if fungicide management strategies are warranted. Where fungicides are required, growers need information on cost effective fungicide control strategies, with consideration of sustaining fungicide mode of action efficacy in the ever increasing risk of fungicide resistance development. As a result, other options need to be investigated. Stubble inoculum loads of NFNB vary significantly following different crop rotations, varieties, fungicide regimes and are directly correlated with subsequent season disease severity and yield loss. The aim of this investment will be to develop and deliver cost effective IDM strategies for NFNB across rainfall zones of the Northern and Southern regions by: * Determine the impact of NFNB by measuring the yield and quality loss incurred in response to the different IDM strategies. * Investigate the decline of NFNB inoculum levels of stubble over time and in different growing environments. * Determine effective stubble management strategies to reduce inoculum load * Develop integrated disease management strategies and determine the cost benefit for implementing IDM strategies in each rainfall zone. * Capture data in a suitable format to be utilised and developed into future modelling required for the evolution of decision support tools, forecasting tools and precision ag’ technologies including apps development within current investment DAW2112-002RTX. * Develop and deliver an extension strategy to drive grower adoption. Extension activity may include, development of communication publications, extension resources and field day and grower update presentations. Communication and extension will leverage existing GRDC resources and investment including AFREN, Online Farm Trials, and the National Risk Management Initiative (NRMI).