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Insect Management for Okra1
S. E. Webb2Okra (Abelmoschus esculentum) is a warm weather crop grown in the summer throughout Florida, but commercial production is concentrated in south Florida where it can be grown most of year. It is often grown as a second crop after more valuable vegetables. Historically, relatively few insecticides and miticides have been registered for use on okra making it difficult to manage insect and mites effectively. Recently, okra has been added to the Fruiting Vegetables Crop Group (tomatoes, peppers, eggplant) and when this change is published in the Federal Register there will be many more options for pest control. Arthropod pests of okra include caterpillars (larvae of Lepidoptera), aphids, thrips, whiteflies, and mites.
Leaf-feeding caterpillar pests (lepidopteran larvae) that attack okra include beet, southern, and fall armyworm, cabbage looper, and corn earworm. Cabbage looper and corn earworm can also bore into pods. Scouting for these pests is essential because the pesticides available (Bacillus thuringiensis products, spinosad, and methoxyfenozide) are most effective on young caterpillars and are less effective on later stages that can defoliate plants. Melon aphid, green peach aphid, and silverleaf whitefly can be very damaging. Imidacloprid will control these sucking insects but effects of a soil application will wear off before the end of the growing season. Melon thrips and southern green stink bug can also cause serious damage and growers have very limited options for control at this time. Spinosad is effective for reducing thrips populations but overuse could lead to the development of resistance and loss of control. Sulfur and bifenazate can be used for mite control. Products containing neem or azadirachtin can be used for all pests of okra but are generally only moderately effective.
Because of limited options for chemical control of insects, conservation of natural enemies is important and possible. As with all crops, destruction of the crop after harvest can help reduce pest populations. The practice of prolonging production by topping plants may contribute to pest problems even though it reduces the cost of production.
Tables
Table 1. Selected insecticides approved for use on insects attacking okra.
Trade Name
(Common Name)
Rate
(product/acre)
REI
(hours)
Days to Harvest
Insects
MOA
Code1
Notes
Acramite 50-WS (bifenazate)
0.75-1.0 lb
12 3 twospotted spider mite
25
One application per season.
Admire 2F (imidacloprid)
16-32 fl oz
12 21 aphids, flea beetles, leafhoppers, foliage feeding thrips, whiteflies
4A
No more than 32 oz per acre.
Admire Pro
7-14 fl oz
Admire 2F (imidacloprid)
0.1 fl oz/1000 plants
12
21
aphids, whiteflies
4A
Planthouse - 1 application to transplants. See label.
Admire Pro
0.44 fl oz/10,000 plants
*Asana XL (0.66 EC) (esfenvalerate)
5.8-9.6 fl oz
12
1
cabbage looper, corn earworm, southern armyworm
3
Florida only.
Aza-Direct (azadirachtin)
1-2 pts, up to 3.5 pts, if needed
4 0 aphids, beetles, caterpillars, leafhoppers, leafminers, mites, stink bugs, thrips, weevils, whiteflies
18B
Antifeedant, repellant, insect growth regulator. OMRI-listed2.
Azatin XL (azadirachtin)
5-21 fl oz
4
0
aphids, beetles, caterpillars, leafhoppers, leafminers, mites, stink bugs, thrips, weevils, whiteflies
18B
Antifeedant, repellant, insect growth regulator.
Biobit HP (Bacillus thuringiensis subspecies kurstaki)
0.5-2.9 lb
4 0 caterpillars (will not control large armyworms)
11B2
Treat when larvae are young. Good coverage is essential. Can be used in the greenhouse. OMRI-listed2.
BotaniGard 22 WP, ES (Beauveria bassiana)
WP: 0.5-2.0 lb/100 gal
ES:
0.5-2 qt/100 gal
4 0 aphids, thrips, whiteflies
--
May be used in greenhouses. Contact dealer for recommendations if an adjuvant must be used. Not compatible in tank mix with fungicides.
Crymax WDG (Bacillus thuringiensis subspecies kurstaki)
0.5-2.0 lb
4 0 caterpillars 11B2
Use high rate for armyworms. Treat when larvae are young.
Deliver (Bacillus thuringiensis subspecies kurstaki)
0.25-1.5 lb
4 0 caterpillars 11B2
Use higher rates for armyworms. OMRI-listed2.
Entrust (spinosad)
0.5-2.5 oz
4 1 armyworms, flower thrips, leafminers, loopers, other caterpillars, Thrips palmi, tomato fruitworm
5
Do not apply more than 9 oz per acre per crop.
Esteem Ant Bait (pyriproxyfen)
1.5-2.0 lb
12
1
red imported fire ant
7C
Apply when ants re actively foraging.
Extinguish ((S)-methoprene)
1.0-1.5 lb
4 0 fire ants 7A
Slow-acting IGR (insect growth regulator). Best applied early spring and fall where crop will be grown. Colonies will be reduced after three weeks and eliminated after 8 to 10 weeks. This is the only fire ant bait that is labeled for use on cropland. May be applied by ground equipment or aerially. Intrepid 2F (methoxyyfenozide)
4-16 fl oz
4 1 beet armyworm, cabbage looper, fall armyworm, hornworms, southern armyworm, tomato fruitworm, true armyworm, yellowstriped armyworm
18A
Do not apply more than 64 fl oz per acre per season.
Javelin WG (Bacillus thuringiensis subspecies kurstaki)
0.12-1.50 lb
4
1
most caterpillars, but not Spodoptera species (armyworms)
11B2
Treat when larvae are young. Thorough coverage is essential. OMRI-listed2.
JMS Stylet-Oil (oil, insecticidal)
3-6 qts/100 gal
4 0 leafminers, mites, whiteflies --
See label for tank mix cautions. Organic Stylet-Oil is OMRI-listed2.
Knack IGR (pyriproxyfen)
8-10 fl oz
12 14 whiteflies (immatures)
7C
Do not make more than 2 applications per season.
Lepinox WDG (Bacillus thuringiensis subspecies kurstaki)
1.0-2.0 lb
12 0 for most caterpillars, including beet armyworm (see label)
11B2
Treat when larvae are small. Thorough coverage is essential.
Malathion 8 F (malathion)
1.5 pt
12 1 aphids 1B
Neemix 4.5 (azadirachtin)
4-16 fl oz
12 0 aphids, armyworms, leafhoppers, leafminers, loopers, whiteflies
18B
IGR and feeding repellant. OMRI-listed2.
Provado 1.6F (imidacloprid)
3.8 oz
12 0 aphids, leafhoppers, whiteflies
4A
Do not apply more than 19.0 oz per acre per year.
Pyrellin EC (pyrethrin + rotenone)
1-2 pt
12 12 hours aphids, leafhoppers, leafminers, loopers, Lygus bugs, plant bugs, mites, thrips, whiteflies
3, 21
Sevin XLR, 4F, 80S (carbaryl)
XLR, 4E: 1-1.5 qt 80S: 1.25-1.88 lb
12 3 corn earworm, stink bugs 1A
Do not apply more than a total of 6 qt or 7.5 lb per acre pre season.
SpinTor (spinosad)
1.5-8.0 fl oz
4 1 armyworms, flower thrips, hornworms, leafminers, Liriomyza spp., Thrips palmi, tomato fruitworm
5
For resistance management, do not use more than 3 times in any 21-day period, then rotate to a different class of products or no insecticide for 21 days. *Telone C-35 (dichloropropene + chloropicrin)
See label
5 days - See label preplant symphylans, wireworms
--
See supplemental label for use restrictions in south and central Florida. *Telone II (dichloropropene)
See label
Trilogy (extract of neem oil)
0.5-2.0% V/V
4 0 aphids, mites, suppression of thrips and whiteflies
18B
Apply morning or evening to reduce potential for leaf burn. Toxic to bees exposed to direct treatment. OMRI-listed2.
The pesticide information presented in this table was current with federal and state regulations at the time of revision. The user is responsible for determining the intended use is consistent with the label of the product being used. Use pesticides safely. Read and follow label instructions.
1 Mode of Action codes for vegetable pest insecticides from the Insecticide Resistance Action Committee (IRAC) Mode of Action Classification v.5.2 December 2006. 1A. Acetylcholine esterase inhibitors, Carbamates
1B. Acetylcholine esterase inhibitors, Organophosphates
2A. GABA-gated chloride channel antagonists
3. Sodium channel modulators
4A. Nicotinic Acetylcholine receptor agonists/antagonists, Neonicotinoids
5. Nicotinic Acetylcholine receptor agonists (not group 4)
6. Chloride channel activators
7A. Juvenile hormone mimics, Juvenile hormone analogues
7C. Juvenile hormone mimics, Pyriproxifen
9A. Compounds of unknown or non-specific mode of action (selective feeding blockers), Cryolite
9B. Compounds of unknown or non-specific mode of action (selective feeding blockers), Pymetrozine
9C. Compounds of unknown or non-specific mode of action (flonicamid)
11B1. Microbial disruptors of insect midgut membranes, B.t. var aizawai
11B2. Microbial disruptors of insect midgut membranes, B.t. var kurstaki
12B. Inhibitors of oxidative phosphorylation, disruptors of ATP formation, Organotin miticide
15. Inhibitors of chitin biosynthesis, type 0, Lepidopteran
16. Inhibitors of chitin biosynthesis, type 1, Homopteran
17. Inhibitors of chitin biosynthesis, type 2, Dipteran
18A. Ecdysone agonist/disruptor
18B. Ecdysone agonist/disruptor (azadirachtin)
20. Site II electron transport inhibitors
21. Site I electron transport inhibitors
22. Voltage-dependent sodium channel blocker
23. Inhibitors of lipid biosynthesis
25. Neuronal inhibitors
2 OMRI-listed: Listed by the Organic Materials Review Institute for use in organic production.
* Restricted Use Only.
Footnotes
1. This document is ENY-466 (IG152), one of a series of the Entomology & Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: July 2002. Revised: September 2007. For more publications related to horticulture/agriculture, please visit the EDIS Website at http://edis.ifas.ufl.edu/.2. S. E. Webb, associate professor, Entomology and Nematology Department, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, 32611-0640.
The use of trade names in this publication is solely for the purpose of providing specific information. UF/IFAS does not guarantee or warranty the products named, and references to them in this publication does not signify our approval to the exclusion of other products of suitable composition. All chemicals should be used in accordance with directions on the manufacturer's label. Use pesticides safely. Read and follow directions on the manufacturer's label.
The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other extension publications, contact your county Cooperative Extension service.
U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Larry Arrington, Dean.
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