P&PDL Picture of the Week for
December 29, 2008

Christmas Tree Ornaments or Arrested Ears?

Bob Nielsen, Extension Corn Specialist, Department of Agronomy, Purdue University

Following a rash of reports from 2007 that blamed the occurrence of arrested ears in corn on foliar applications of fungicide prior to tasseling, several of us at the Purdue Crop Diagnostic Training & Research Center set out to reproduce the symptoms in a preliminary trial at the Agronomy Farm near West Lafayette in 2008. The upshot of that trial is that we indeed were able to reproduce the symptoms. The surprising result was that the problem was not caused by fungicides, but rather appears to be related to physical injury to the developing ear shoot by absorption of one or more spray adjuvants. For "the rest of the story", see the online summary at http://www.kingcorn.org/news/articles.08/ArrestedEars-1209.html.

Click image to enlarge

Arrested ears

Arrested ears

Arrested ears

Arrested ears

Purdue Plant & Pest Diagnostic Lab Purdue Cooperative Extension Service