Beneficial impacts of the combined use of rain shelters and reflective groundcovers in an organic raspberry cropping system

During the summers of 2008 and 2009, rain shelters and white, synthetic reflective groundcovers were placed in a red raspberry (Rubus idaeus) organic cropping system in southeastern New Brunswick to assess their independent and combined effects on microclimate, raspberry crop productivity, fungal disease pressure, and ground arthropods involved in natural pest control. Reflective groundcovers enhanced the light environment quality. Rain shelters decreased the severity of Didymella applanata infections by ca. 50% and reduced the rate of post-harvest raspberry degradation caused by Botrytis cinerea in comparison with the control treatment. Of all the combinations of treatments, rain shelters paired with reflective groundcovers provided the best results by increasing the marketable yield of raspberries by ca. 200% in comparison with the control treatment. No detrimental effects of the structures were detected on ground beetle communities. Based on this, it is suggested that the combination of these two structures constitutes a promising approach to counter certain adverse effects caused by untimely precipitation while maintaining a productive cropping system and without being detrimental to ground beetle species that may confer pest control services.