Andrea Podavkova
Senior Engineer
(+47) 414 99 474
andrea.podavkova@nibio.no
Place
Ullensvang
Visiting address
NIBIO Ullensvang, NO-5781 Lofthus
Abstract
Ascospore release by the European apple canker fungus Neonectria ditissima was examined by means of continuously running spore traps mounted over detached segments of apple tree branches with cankers habouring maturing and ripe perithecia, or placed within tree rows in apple orchards. Records began in autumn 2017 and continued for nearly 3 years at two locations in Norway, and for five autumn to late spring periods at two locations in the Lower Elbe region of northern Germany. In northern Germany, the first ascospore releases were recorded during or after autumnal leaf fall, whilst major peaks occurred from March to May. In Norway spore discharge began in spring with a major peak, continued through the summer and autumn, and paused in mid-winter. These observations indicate that in northern Germany, ascospores are less likely to contribute to fruit and leaf scar infections than in Norway. Furthermore, ascospore discharge events in spring, which were recorded in all sampling years at all sites, were associated with the same rain events as those of the apple scab fungus Venturia inaequalis, and would have been covered by intensive fungicide sprays. For northern Germany, these results indicate a shift in major ascospore release peaks from autumn towards spring as compared to previous data collected some 50 years ago.
Authors
Jorunn Børve Katharina Pampus Tuuli Haikonen Andrea Podavkova Gaute Myren Roland W. S. WeberAbstract
No abstract has been registered
Abstract
No abstract has been registered