Abstract

Late blight is the most devastating disease of potato, the control of which provides for the use of fungicides. To reduce the volumes of chemical treatments, the risk of late blight outbreaks and the level of corresponding yield losses should be adequately evaluated. Using the earlier developed mathematic simulator and retrospective data obtained from 415 weather stations for the last 15 years, a map was constructed reflecting the potential risk of such losses in Russia. The area of a zone with high average annual yield losses (>20%, red zone) occupies 41.3% of the total studied area, while zones with moderate (yellow zone) and low (< 10%, green zone) yield losses occupy 43.7 and 15.0%, respectively. Additionally, a geoinformation system for assessment and mapping of risks of the late blight outbreaks in a real-time mode has been developed and introduced as a part of the meteorological service of the Infometeoservice company available at http:// infometeos.com/Map/Data/. The data on the current risk levels can be used by potato-growers to make decision in relation to crop protection activities. The geosystem can be used to monitor the late blight development and to determine the optimum terms of protective treatments of potato during a vegetation season.