An app for apples: Citizen-led mapping of fire blight in Central Asia.

Fire blight, caused by the bacterial pathogen , is a severe bacterial disease of apple and pear that can quickly destroy whole plants. In the last decade, it was also detected in Central Asia, where wild pomaceous fruit plants represent the dominant species in mid-altitude forests and constitute a critical foundation for the entire ecosystem. Efficiently informing farmers, forestry services and private persons about the instances and dangers of fire blight, the correct way to recognize the symptoms, and the methods of disease control is thus of paramount importance in a vast and fragmented natural landscape like the one characterizing countries like Kyrgyzstan, Kazakhstan and Tajikistan. For that purpose, we have developed an app for smartphones and mobile devices that can inform stakeholders about fire blight, simultaneously allowing a citizen science approach for mapping the spread of the disease in Central Asia. The app is available in the three national languages as well as in Russian, English, and German, and can easily be adapted to new countries, languages or even diseases.