Corn: Corn Leaf Aphid (Rhopalosiphum maidis)

Pub 812: Field Crop Protection Guide > Chapter 1: Corn > Corn Leaf Aphid

Field Crop Protection Guide 2011-2012, Order 2011-2012 publication

Table of Contents

  1. Description
  2. Integrated Pest Management Options
  • endosulfan - Thiodan 4 EC, Thionex EC
  1. Related links...

Description

These aphids are small (2mm or less), bluish green, soft-bodied insects with black legs and short black cornicles ("tailpipes") near the rear of the abdomen. They have piercing and sucking mouthparts and feed on the juices (nutrients) of young plant tissue (tassel and whorl). They secrete a sticky substance referred to as "honeydew," which can become coated with a blotchy, sooty mould.

Image 1. Corn leaf aphids clustered on corn ear. Tassels and silks may become coated with honeydew, reducing pollination success.
Image 1. Corn leaf aphids clustered on corn ear. Tassels and silks may become coated with honeydew, reducing pollination success.

Integrated Pest Management Options

Aphids are rarely a problem in corn in Ontario. Spray only if populations exceed 400 aphids per plant on average.

 
Active ingredient endosulfan
Trade name Thiodan 4 EC
Rate per hectare (product) 2.75 L per ha
Rate per acre (product) 1.1 L per ac
PHI* 50
Comments Ground application only. Maximum 2 applications/yr. 48-hr re-entry period.

 

 
Active ingredient endosulfan
Trade name Thionex EC
Rate per hectare (product) 2.75 L per ha
Rate per acre (product) 1.1 L per ac
PHI* 50
Comments Ground application only. Maximum 2 applications/yr. 48-hr re-entry period.

 

Related links...

 


For more information:
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Local: (519) 826-4047
E-mail: ag.info.omafra@ontario.ca
Author: OMAFRA Staff
Creation Date: 2 May 2011
Last Reviewed: 10 May 2011