2019 ASHS Annual Conference

A novel plant cuticle supplement, HydroShield, was formulated in Milton-Freeewater and refined by the authors through multiple laboratory tests. A field prototype was applied four times at 0.5% in 60 gal per acre to 'Cabernet Sauvignon' Clone 8. Vines were irrigated with drippers delivering either 0.75 gal per hour (25% reduction in irrigation water) or 0.5 gal per hour (50% reduction in irrigation water) and compared against an untreated check which received 1.0 gal per hour (0% reduction). Vines were grown under deficit irrigation and multiple techniques were adopted to ensure vigor was contained, including pressure bomb, soil moisture monitoring using gypsum block as well as monitoring tendril development. In addition, soil moisture was monitored at 4 depths (100, 200, 300 and 400 mm) on a weekly basis using a Delta T HH2 device. In 2017, soil moisture at all depths was comparable between treatments however, at the 400 mm depth of vines grown under 50% reduction irrigation water began to dry out at the end of the growing season compared to . Veraison was accelerated by 7 days in the 25% reduction but reduced by 3 days for the 50% reduction compared to the untreated check. Yields, berry size, TSS, acidity, flavonoid and phenolic panels for all the grapes were not significantly different between treatments or the check. In 2018, soil moisture across the season was similar to the previous year however, there was more soil moisture in the 25% reduction in conjunction with HydroShield when compared to the 0% reduction which suggests water savings. Shoot length and number were measured for all treatments to determine whether less growth accounts for the less water usage. Yields of the 25% reduction in irrigation water were again not significantly different from the untreated check however the 5o% reduction in irrigation water resulted in significantly lower yields the the 25% or 0% reduction treatments. Version was again accelerated by the 25% reduction but retarded by the 50% reduction. Fruit quality parameters as before were not significantly different when comparing all treatments agains the untreated check. Differences in phenolic and flavonoid panels will be reported on.