HortResearch has developed a national network of electronic weather stations to monitor infection risk according to standardized criteria. The system is fully commercialized in some districts and is at an advanced stage of testing in others. Growers can buy access to weather stations nearest to their orchards and buy PC software to ring up the weather stations and to interpret black spot infection risk. In some districts daily facsimile reports on infection risk are available. The system will continue to be developed and improved for some time to come, but it already offers high quality hourly data with the full research back-up of HortResearch.
Weather forecasts are also an important part of black spot risk prediction and fungicide management.
HortResearch has done several years of research with the New Zealand Meteorlogical Service on the development and use of black spot weather forecasts and these are proving to be a vital part of black spot management. Although forecasts of rain are not accurate enough to allow growers to only apply protectants when rain is predicted, forecasts of extended fine periods are accurate enough to safely delay some protectant applications that would otherwise be applied on a weekly basis. Obviously there is greatest scope for use of this approach in drier districts where extended fine periods occur frequently, such as Hawkes Bay, Canterbury and Otago. Black spot weather forecasts are being commercialized in several districts and HortResearch is involved in teaching growers how to make best use of them. The prevention of primary infection is crucial to effective black spot management.