Reducing the risk of importing pest-infested citrus by applying high pressure washing treatments offshore

Abstract

New Caledonia exports limes to New Zealand and Australia each year. In 2011, a high pressure washing (HPW) system was installed in an existing fresh lime grading line in La Tontouta, New Caledonia. Since then, fumigation of limes has decreased from 100% of shipments prior to 2011 to 5.8% in 2012 and 1.2% in 2013 (from 173 and 82 shipments respectively). This paper reports on trials undertaken over the last 2 years while installing, modifying, testing and commercially operating the HPW system for lime exports. Fruit quality and removal of pests (mainly Glover's scale ( Lepidosaphes gloverii) and mussel scale (Lepidosaphes beckii)) indicated that a 175 psi (1207 kPa) HPW treatment under a gantry of seven rows of two angled nozzles resulted in up to 97% removal of pests and >84% of heavily infested limes being clean of pests, with no adverse effect on fruit quality.