Reusing Plastic Mulch for a Second Strawberry Crop: Effects on Arthropod Pests, Weeds, Diseases and Strawberry Yields

Abstract

Florida is the second largest producer of fresh-market strawberries (Fragaria × ananassa Duchesne; Rosales: Rosaceae) in the United States. The annual hill “plasticulture” production system used to grow strawberries makes this crop one of the most expensive to produce. The cost of production may be reduced if synthetic mulch can be reused and the dead plants (thatch) from the previous season left in the field, without negatively affecting crop yields. Field studies were conducted during the 2010/2011 and 2011/2012 strawberry growing seasons to evaluate the effect of re-using plastic mulch with or without dead strawberry plants from the previous season on arthropod populations, disease incidence, weeds and strawberry growth, and marketable yields of strawberries. The study was conducted in a commercial field in Citrus County, Florida using 2-yr old synthetic mulch on the bed. Two strawberry varieties ‘Albion’ and ‘Florida Festival’ were planted in 2010/2011 and 2011/2012 growing seasons, respectively. During transplanting, one treatment had all strawberry thatch (dead plant debris from previous season) removed from the soil before planting the new strawberry transplants, while in the second treatment the thatch was left to grow with the transplants. Data were collected throughout the growing seasons on plant growth, spider mites and insect pest populations, weeds, disease incidence, and marketable yield of strawberries. Re-using plastic mulch with or without strawberry thatch had no significant effect on plant size or populations of beneficial and pestiferous arthropods. However, re-using mulch with strawberry thatch reduced weed growth but increased the incidence of fungal diseases. As a result of fungal diseases and plant mortality, marketable yield for the variety “Florida Festival”, but not “Albion” was significantly lower in plots with the strawberry thatch than in those without thatch.