Annual and regional variability in adult <i>Dasineura mali</i> (apple leafcurling midge) emergence in New Zealand

  • P.L. Lo The New Zealand Institute for Plant & Food Research Limited, Private Bag 1401, Havelock North 4157, New Zealand
  • J.T.S. Walker The New Zealand Institute for Plant & Food Research Limited, Private Bag 1401, Havelock North 4157, New Zealand
Keywords: Cecidomyiidae, Dasineura mali, apple, phenology

Abstract

Apple leafcurling midge is an important quarantine pest for New Zealand apple exports. Season-long pheromone trapping was conducted in Hawke’s Bay and Nelson from 2004–2017, and from 2012–2017 in Central Otago. Four generations occurred annually in Hawke’s Bay and Nelson and 3–4 in Central Otago. In Hawke’s Bay and Nelson, the timing of each peak varied by about 3–4 weeks between years, while the difference was ~2–3 weeks in Central Otago during fewer years of monitoring. Hawke’s Bay was up to a month earlier than Central Otago for the same peak within individual years. The major factor behind this variability was the accumulated number of growing degree-days. Insecticide sprays target midge larvae, but are timed against the second and third peaks of adult emergence. Variations in the timing of these peaks annually and across the main pipfruit growing regions, mean that specific insecticide timing recommendations are necessary each year for each region.

Published
2017-08-08
How to Cite
Lo, P., & Walker, J. (2017). Annual and regional variability in adult <i>Dasineura mali</i&gt; (apple leafcurling midge) emergence in New Zealand. New Zealand Plant Protection, 70, 131-136. https://doi.org/https://doi.org/10.30843/nzpp.2017.70.38
Section
Vol 70 Horticultural Insects 2017