Screening for Resistance to Fruit Rot in Strawberries and Red Raspberries: A Review1

Fruit rots are probably the most important diseases of small fruit crops. Current statistics are not available for all small fruit crops, however, losses of strawberry fruit to pre- and postharvest fruit rots may conservatively be in the millions of dollars annually to growers, processors, and retailers. Losses from fruit rots vary from year to year and from locality to locality according to weather conditions prevailing during harvest. During wet weather, 30-50% or more of a strawberry crop may be lost to Botrytis rot, even with liberal use of fungicides. This, coupled with an increasing concern with development of fungicide-resistant strains of rot-causing organisms, particularly Botrytis cinerea Pers. ex Fr., and the development of mechanical harvesting methods have intensified the need to identify small fruit germplasm sources for fruit rot resistance.