GNOMONIA COMARI ON STRAWBERRY: PRELIMINARY STUDY ON CONTROL STRATEGY IN THE NORTH OF ITALY

In the autumn 2005, in the province of Forlì-Cesena (Emilia-Romagna), several strawberry plots were affected by the fungus Gnomonia comari. During the growing season, more than 50% of the foliage was blighted by the epidemic causing severe yield losses. Disease severity is mainly due to the use of susceptible cultivars (Alba) and wet climate in autumn. In the following spring two trials were set up with the aim to: 1) evaluate the efficacy of six fungicides on foliage, applied from beginning of the vegetative growth until bloom; 2) evaluate the efficacy of four fungicides applied from bloom to harvest to control both foliage and fruits. In trial 1, two surveys were carried out on foliage. The results showed that pyraclostrobin+boscalid , azoxystrobin and miclobutanil were the most effective in controlling the foliage blight. Slightly less effective were cyprodinil+fludioxonil, penconazole and tolylfluanide. In trial 2, one survey on foliage and three on fruits were carried out. On leaves, in spite of the fact that chemicals were applied after the occurrence of the symptoms in the field, pyraclostrobin+boscalid and azoxystrobin allowed to better reduce the epidemic compared with the check. Cyprodinil+fludioxonil was less effective, while tolylfluanide was not statistically different from the check. On fruits, pyraclostrobin+boscalid, cyprodinil+fludioxonil and azoxystrobin proved to be the most effective, while tolylfluanide failed to give satisfactory results.