HPIPM:Aphids
From Bugwoodwiki
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Author: Gary L. Hein
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Across the region aphids are not a common problem in sugarbeet. Aphid presence in sugarbeet will primarily manifest itself in the occurrence of viruses (beet western yellows and beet mosaic viruses) that the aphids are capable of transmitting. These viruses can be found in the region but are seldom of any consequence. A newly identified virus, beet chlorosis virus, has been found in Colorado. The vector for this disease is unknown, but aphids could be involved in its transmission.
Identification (life cycle and seasonal history)
The green peach aphid, Myzus persicae, is the most likely aphid to transmit viruses to sugarbeet in the region. Wingless forms are tear-dropped shaped and light green to light pink in color. Winged adults will be darker with a brown to black thorax and a greenish abdomen. Overwintering of the green peach aphid is not well understood, but if it does overwinter in the region, it would overwinter as eggs on Prunus species (various types of plum and cherry). A spring generation would occur on the overwintering host, and winged aphids would leave this host in early summer (June) in search of numerous summer hosts, including sugarbeet.
A second aphid found in sugarbeet in the region is the bean aphid, Aphis fabae. The bean aphid is blue-black in color, and overwinters in the egg stage on Euonymus bushes. These aphids also will spend a generation in the spring on their overwintering host, and then move to sugarbeet and other summer hosts.
Plant Damage and Response
Aphids suck sap from the plant, causing leaf curling and puckering. Severely damaged leaves may turn yellow. The most important aspect of aphid presence in sugarbeet is its ability to transmit viruses. The green peach aphid is the most effective vector of western yellows and beet mosaic viruses. Bean aphids, however, are more likely to cause direct plant damage to sugarbeet.
Management
The diseases that result from aphid-transmitted viruses do not occur often and are impossible to predict. We understand very little about the life cycle of the green peach aphid and the bean aphid in the region. Treatments to control virus transmission are not likely to be effective. Treatments to prevent direct aphid damage should only be considered if leaf symptoms (curling, stunting) are present on plants less than 8-12 weeks old and active aphid colonies are present.
Product List for Aphids—Note: not for sugarbeet root aphid.
| Insecticide | Product per Acre | Preharvest Interval, remarks |
|---|---|---|
| Counter 15GR, CRR | 15G: 4.0-8.0 oz./1000 ft.
CR: 3.0-6.0 oz/1000 ft. | Apply at planting or post-emergence;
may be banded (PHI 110 days) or knifed in (PHI 150 days); REI 72 hrs. |
| Methyl 4ECR
(methyl parathion) | 0.5-0.75 pts./A | PHI 20 days (60 days if tops fed to
animals); REI 5 days. |
| Diazinon 50WR, AG500R | 50W: 0.75-1.0 lbs./A
AG500: 0.75-1.0 pt./A | PHI 14 days; REI 24 hrs. |
| Lannate WSPR, LVR | WSP: 0.25-1.0 lbs./A
LV: 0.75-3.0 pts./A | PHI 7 days; REI 48 hrs. |
| Malathion 57 EC1 | 1.5-2.0 pts./A | PHI 7 days; REI 12 hrs. |
| Metasystox-RR,1 | 1.5-3.0 pts./A | PHI 30 days; REI 72 hrs. |
| Temik 15GR | 7.0-14.0 lbs./A | Apply at planting or post-emergence.
Potential for groundwater contamination. See label for environmental precautions and restrictions. PHI 90 days; REI 48 hrs. |
| Thimet 20GR | 4.5 oz/1000 row ft
4.9-7.5 lbs/A | At plant: Do not place in contact with
seed. REI 72 hrs. Apply postemergence to dry foliage in band;PHI 30 days; REI 72 hrs. |
| Seed Treatment | ||
| Gaucho 480 | 3.0-6.3 oz / unit seed | If rates exceed 3.0 oz/unit seed must be pelleted. |
| RRestricted use pesticide 1Labeled for chemigation. | ||
The information herein is supplied with the understanding that no discrimination is intended and that listing of commercial products, necessary to this guide, implies no endorsement by the authors or the Extension Services of Nebraska, Colorado, Wyoming or Montana. Criticism of products or equipment not listed is neither implied nor intended. Due to constantly changing labels, laws and regulations, the Extension Services can assume no liability for the suggested use of chemicals contained herein. Pesticides must be applied legally complying with all label directions and precautions on the pesticide container and any supplemental labeling and rules of state and federal pesticide regulatory agencies. State rules and regulations and special pesticide use allowances may vary from state to state: contact your State Department of Agriculture for the rules, regulations and allowances applicable in your state and locality.
