Can biological products control <i>Neonectria ditissima</i> picking wound and leaf scar infections in apples?

  • M. Walter The New Zealand Institute for Plant & Food Research Ltd (PFR), 55 Old Mill Road, RD3, Motueka, New Zealand
  • R.E. Campbell The New Zealand Institute for Plant & Food Research Ltd (PFR), 55 Old Mill Road, RD3, Motueka, New Zealand
  • N.T. Amponsah PFR, Havelock North Research Centre, Corner Crosses and St Georges Road, Havelock North, New Zealand
  • L. Turner The New Zealand Institute for Plant & Food Research Ltd (PFR), 55 Old Mill Road, RD3, Motueka, New Zealand
  • D. Rainham AgFirst Ltd, 171 High Street, Motueka, New Zealand
  • U. Kerer AgFirst Ltd, 171 High Street, Motueka, New Zealand
  • R.C. Butler PFR, Canterbury Agriculture & Science Centre, Gerald Street, Lincoln, New Zealand
Keywords: disease control, European canker, biological fungicides

Abstract

Neonectria ditissima is the causal agent of European canker in apple, and conidia infect wounds in apple trees. Several commercially available chemical fungicides and biological products (BPs) were tested for wound protection activity in three field experiments (2014–17). Freshly made wounds (rasp, picking, leaf and/or bud scar) were sprayed with the products at label rates. Wounds were challenge-inoculated with N. ditissima conidia after 24 hours and monitored monthly for lesion development. Only captan and copper oxide consistently protected wounds from infection and disease development in each experiment. The BPs tested in this study did not provide adequate wound protection when challenge-inoculated with N. ditissima at high concentration (>1000 spores/wound) so are not recommended for wound protection during harvest and leaf fall when disease pressure is high.

Published
2017-08-08
How to Cite
Walter, M., Campbell, R., Amponsah, N., Turner, L., Rainham, D., Kerer, U., & Butler, R. (2017). Can biological products control <i>Neonectria ditissima</i&gt; picking wound and leaf scar infections in apples?. New Zealand Plant Protection, 70, 63-72. Retrieved from http://journal.nzpps.org/index.php/nzpp/article/view/29
Section
Vol 70 Apple Pathology 2017