Development of best practice to minimise offtarget drift from hydrogen cyanamide sprays in kiwifruit orchards

Abstract

The use of air inclusion nozzles on airblast sprayers markedly reduced offtarget spray drift in applications to dormant kiwifruit vines The addition of a new driftreducing adjuvant at rates of ge;50 ml/100 litres maintained cane deposits at levels similar to those of conventional cone nozzle applications The addition of the adjuvant at rates above 100 ml/100 litres improved drift control in higher winds (ca 2 m/s) Prescriptions for AI nozzles and adjuvant use have been included in Best Practice Spraying Guidelines for New Zealand kiwifruit growers Industry uptake was ca 40 by kiwifruit spraying contractors in the 2007 season and is expected to increase to >80 by 2009