Continuous Monitoring of Wine Grape Canopy Temperature forIrrigation Management

摘要

Automated monitoring of plant water status is a prerequisite for precision irrigation and water conservation. The objective of this study was to assess the potential for using a thermal-based crop water stress index (CWSI) as an irrigation managementtool to assist with scheduling irrigation events and estimating irrigation amounts for selected wine grape cultivars in the arid Northwest U.S. The temperature of the vine canopy, soil volumetric water content, vineyard environmental conditions, irrigation events and amounts were continuously monitored infield plots of the wine grape cultivars Malbec and Chardonnay at three commercial vineyards in southwestern Idaho during the 2017 growing season. Select measured and calculated parameters were made available in real-time to vineyard managers on a website hosted by the data logger via cell phone modem. At all sites, the daily CWSI rapidly decreased during and following an irrigation event and gradually increased between irrigation events, indicating sensitive and rapid response to changes in available soil moisture. Throughout the growing season, the change in CWSI value reflected the relationship between plant available soil water (PASW) and the water stress coefficient (Ks) of the Penman-Monteith equation for estimating plant water demand. Data analysis suggests that automated calculation of a daily CWSI through continuous remote monitoring of vine canopy temperature and vineyard environmental conditions can be used to guide irrigation scheduling and estimate the reduction in vine water demand when transpiration is restricted by soil water availability.