IMPROVING IRRIGATION MANAGEMENT AND ROW COVER USE IN STRAWBERRY PRODUCTION IN THE MID-ATLANTIC REGION

Abstract

Irrigation strategies that reduce water application and improve water use efficiency could be useful in strawberry production, to save water and reduce the environmental impact of nutrient leaching. Therefore, the effect of moisture availability on the physiology, growth, yield and fruit quality of strawberry (Fragaria X ananassa) was studied under field and greenhouse conditions by implementing deficit irrigation at decreasing matric potentials. Incremental drought stress significantly affected crop physiology, growth and yield, but not fruit quality. The results revealed both physiological and morphological adaptations of strawberries to incremental drought stress that are typical of isohydric plants. Since reduced irrigation applications led to proportional yield losses, there was no significant improvement in the irrigation water use efficiency/water productivity of the crop. Economic analysis showed that the loss of revenue as a result of reduced yields was of a much higher magnitude than the savings associated with reduced irrigation application, making adoption of reduced irrigation strategies such as deficit irrigation unlikely. Nevertheless, results revealed that soil moisture measurement-based irrigation management can be used to improve current (excess irrigation) grower practices, without impacting revenue. The effect of row covers on canopy and soil temperature, was studied in plasticulture strawberry production to more quantify their effects on crop phenology and frost mitigation. Row cover use increased the average temperature measured in the canopy and soil by 6.9 and 9.8%, respectively. Although this seems relatively insignificant, these temperature increases translated to an 84 and 122% increase in growing degree-day accumulation at the canopy and in the soil during a fall study period. In addition, increases in soil temperature were positively correlated with soil moisture. These results indicate the advantages that row covers can provide to growers, as a tool to enhance plant growth and for freeze and frost protection of plants. However, growers need to monitor environmental conditions at canopy level under row covers and in the ambient air in order to gain these benefits without negative consequences for yield.