The effect of air flow rate and forward speed on spray deposition from a vineyard sprayer

Two air flow rate (4.7 m3/s and 7.1 m3/s) and two forward speed treatments (6 km/h and 9 km/h approx.) were compared at the beginning of flowering and the berry touch stages in a Casarsa-trained vineyard by using a randomised-blocks design with four replicates. The sprayer was an Ecologic 2000 T800 model fitted with an axial-flow fan and six Albuz ATR nozzles on each side, placed at the lateral outlets of a fishtail air conveyor. Analysis of variance of the mean foliar deposits showed no significant effects owing to either the air flow rate and the travel speed or their interaction at both growth stages. However, at beginning of flowering, the lower air flow rate significantly increased mean deposition in the inside of the canopy. At full foliage (berry touch) stage, the higher travel speed slightly increased deposits on the canopy side nearest the sprayer, while decreased them on the opposite side. Further research is being planned in order to optimise the air flow rate and the travel speed in vineyards with narrower row distances.