Special Problems in Nursery Propagation of Day-neutral Strawberry Cultivars Susceptible to Colletotrichum acutatum.

Susceptible day-neutral strawberry (Fragaria xananassa Duch.) cultivars are readily infected by Colletotrichum acutatum J.H. Simmonds during nursery propagation. The fungus infects strawberry flowers and fruit under warm, moist conditions and spreads rapidly throughout the nursery planting during repeated cycles of infection. Plants transplanted from infected nurseries into fruit-production fields have increased plant mortality and yield loss. This paper reviews practices adopted by California strawberry nurseries that reduce or eliminate sources of fungal inoculum, reduce strawberry plant susceptibility, or reduce pathogen spread in the nursery. California nurseries are currently using a combination of these practices to produce specific pathogen-free planting stock of susceptible day-neutral cultivars. [ABSTRACT FROM AUTHOR]