Spray retention models for vegetable crops preliminary investigation

Abstract

This study tests the most appropriate of three mathematical models for spray retention by plant foliage The current study utilised two plant species potato (easy to wet with relatively horizontal leaves) and onion (difficult to wet with relatively vertical foliage) Formulations providing a range of dynamic surface tensions (2673 mN/m) were used at two nominal spray volumes (200 and 500 litres/ha) The model by Grayson et al (1993) worked reasonably well with the current data However to be truly predictive extensive revision is required and recommendations for this are outlined