A good health status and quality of roots during winter storage especially in soil clamp is a serious economic problem. The proper plant protection in the field can reduce the occurrence of pathogens mainly those infecting at first leaves and then causing root rots such as fungi of
There was no clear effect of a specific treatment on the total yield of carrot, but a tendency of a higher crop from the plots treated with fungicides was noticed as compared to the untreated control. A significant influence of applied agents was visible after the storage period. The lowest root weight losses were observed from the treatments protected with chitosan and grapefruit extracts. Untreated control produced the highest weight losses of roots in both years of experiment. Laboratory tests revealed numerous colonies of fungi and bacteria on the diseased carrot tissues. Dominating microorganisms were fungi from