Soybeans: Bean Leaf Beetle
(Certoma trifurcata)
Pub 812: Field Crop Protection
Guide >
Pub 812:
Soybeans > Bean Leaf Beetle
Field Crop Protection Guide 2011-2012, Order
2011-2012 publication
Table of Contents
- Description
- Seed Treatment
- thiamethoxam – Cruiser 5 FS
- thiamethoxam + metalaxyl-M + fludioxonil - Cruiser Maxx
Beans
- Foliar Treatment
- cyhalothrin-lambda – Matador 120 E
- cyhalothrin-lambda – Silencer 120 EC
- dimethoate – Cygon 4 E, Lagon 480 EC
- imidacloprid + deltamethrin - Concept
- Related links...
Description
The bean leaf beetle adult is around 5 mm in length (small) with
four black spots usually found on the wing covers. Adult beetles
can vary in colour but are most often yellow-green, tan or red.
A small, black triangle is visible at the base of the wing covers
(the prothorax - behind the head). The margins of the wing covers
have a black border.
Image 1. Bean leaf beetle adults vary in colour,
but always have a small black triangle visible behind the head.
They may or may not have four spots.
The bean leaf beetle is often confused
with the spotted cucumber beetle. A small black triangle is visible
at the base of the wing covers (behind the head) of the bean leaf
beetle.
Integrated Pest Management Options
Seed Treatment
Seed treatment is recommended for those fields with a history of
early-season infestation from overwintering adults. Fields in southwestern
counties of Ontario in particular tend to experience injury to the
seedling crop from early infestations of beetles.
| Active ingredient |
thiamethoxam |
| Trade name |
Cruiser 5 FS |
| Rate (product) |
83 mL per 100 kg seed |
| Comments |
For use in commercial seed treatment facilities only.
To reduce early-season defoliation. Do not graze or feed livestock
on treated areas for 45 days after planting. |
| Active ingredient |
thiamethoxam + metalaxyl-M + fludioxonil |
| Trade name |
Cruiser Maxx Beans |
| Rate (product) |
195 mL per 100 kg seed |
| Comments |
For use in commercial seed treatment facilities only.
To reduce early-season defoliation. Compatible with Rhizobium-based
inoculants. Check with inoculant manufacturers for details prior
to use. Do not graze or feed livestock on treated areas for
45 days after planting. |
Foliar Treatment
For protection from overwintering adults, in areas with history
of injury, consider using insecticide seed treatment for early-planted
soybeans.
Bean leaf beetle populations rarely cause enough defoliation after
the seedling stages to require a foliar insecticide application
in Ontario. Defoliation thresholds during the R1-R5 stage are listed
in the OMAFRA Publication 811, Agronomy Guide for Field Crops.
Food-grade and seed soybeans may require protection, especially
during the later R5 and R6 pod stages to reduce pod disease development
caused by beetle feeding. If 10% of pods have feeding damage, insecticide
may be necessary. Pay attention to preharvest intervals when spraying
during the R6 stage of soybeans.
| Active ingredient |
cyhalothrin-lambda |
| Trade name |
Matador 120 E |
| Rate per hectare (product) |
83-233 mL per ha |
| Rate per acre (product) |
34-94 mL per ac |
| PHI* |
21 |
| Comments |
Ground and aerial application. For best results, apply during
the early morning, before temperatures rise,or during the evening,
past the heat of the day. Use 100-200 L water/ha for ground
application, 10-40 L water/ha for aerial application. Maximum
3 applications/yr. 24-hr re-entry period. |
| Active ingredient |
cyhalothrin-lambda |
| Trade name |
Silencer 120 EC |
| Rate per hectare (product) |
83 mL per ha |
| Rate per acre (product) |
34 mL per ac |
| PHI* |
21 |
| Comments |
Ground application only. For best results,
apply during the early morning, before temperatures rise, and
during the evening, past the heat of the day. Maximum 3 applications/yr.
24-hr re-entry period. |
| Active ingredient |
dimethoate |
| Trade name |
Cygon 4 E |
| Rate per hectare (product) |
0.7-1 L per ha |
| Rate per acre (product) |
280-400 mL per ac |
| PHI* |
30 |
| Comments |
Ground and aerial application. Use sufficient water volume
to ensure good coverage. Maximum 3 applications/yr. |
| Active ingredient |
dimethoate |
| Trade name |
Lagon 480 EC |
| Rate per hectare (product) |
0.7-1 L per ha |
| Rate per acre (product) |
280-400 mL per ac |
| PHI* |
30 |
| Comments |
Ground and aerial application. Use sufficient water volume
to ensure good coverage. Maximum 3 applications/yr. |
| Active ingredient |
imidacloprid + deltamethrin |
| Trade name |
Concept |
| Rate per hectare (product) |
325-650 mL per ha |
| Rate per acre (product) |
131-263 mL per ac |
| PHI* |
20 |
| Comments |
Provides suppression only. Do not apply this product if following
a seed treatment or soil application of a Group 4 insecticide
(neonicotinoids) within that season. Ground application only.
Use high rate for fastest knockdown and best residual control.
Minimum of 5 days between applications. Maximum 3 applications/yr.
24-hr re-entry period. |
Related links...
