Impact of Different Soil Moisture Regimes on Cranberry (Vaccinium macrocarpon) Vine Physiology

Water is an essential resource for cranberry production, and producers are continuously looking for new ways to improve water use efficiency. While large amounts of water are used in pest management, crop protection and harvest, these applications are recyclable, unlike irrigation which contributes the largest amount of water consumption, as well as the costs of fuel to run the pumps. Therefore, the impact of reduced irrigation is being studied to better understand the effects on the vine physiology, and ultimately crop yield. Preliminary findings have suggested that the short term affects of reduced irrigation had no adverse impact on the vine physiology and yield, but little is known about the long term outcomes. This experiment is a component of a larger, long term study to determine the impact of different soil moisture regimes on the physiological mechanisms of the vine, with a focus on photosynthesis. Two soil moisture treatments, wet and dry were established in a 5A commercial cranberry bed. The two treatments were irrigated independently based on their pre-determined matric potentials. Bi-weekly measurements of photosynthesis, chlorophyll fluorescence, and xylem potential were monitored, and prior to harvest flower counts and fruit set counts were also observed. We expect that irrigation can be reduced considerably with no adverse affects on plant physiology, growth and yield.