At-Plant Soil Insecticide Applications: Best Management Practices for Leafy Vegetables and Cole Crops

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1 Technical Update From DuPont Crop Protection At-Plant Soil Insecticide Applications: Best Management Practices for Leafy Vegetables and Cole Crops For use on selected vegetables for control of labeled lepidopteran worm pests, dipteran leafminer and suppression of whitefly DuPont Coragen insect control soil applications provide growers with flexible and alternative application methods that deliver excellent pest control and crop safety with a favorable environmental profile. Coragen insect control is a suspension concentrate formulation that controls many important insects. For maximum flexibility, it can be applied using any of the following methods to certain labeled vegetable crops. See product label for specific application methods allowed by crop: Soil shank injection at planting (direct seeded or transplants) In-furrow spray at planting Surface band at planting Transplant water treatment Drip chemigation Foliar spray Applied at-planting, Coragen must be mixed with water prior to application. Coragen At-Plant Soil Application Guidelines and recommendations for Vegetable Crops Coragen may be applied at-planting to leafy vegetable and brassica (cole) crop groups which are direct seeded or transplanted. These crops include, but are not limited to, head and leaf lettuce, broccoli, cauliflower, cabbage, celery and spinach. See product label for complete list of crops. Coragen offers proven protection of labeled vegetable crops through effective and long-lasting control of larval stage lepidopterous insect pests, including beet armyworm, cabbage looper, diamondback moth and corn earworm. Following ingestion by lepidopterous pests, Coragen goes to work rapidly to stop destructive feeding and damage to seedling vegetables. At-plant soil applications will provide plant protection starting from crop emergence through young developing plants (generally 25 to 30 days of plant protection). At-plant, residual protection of Coragen offers continuous and more uniform crop protection against destructive lepidopterous pests. This is a significant advantage to foliar applications of most insecticides that must be applied repeatedly for an equivalent length of control. At-plant soil applications must be placed properly and uniformly in the root zone for effective results.

2 A higher range of rates are required at-planting to protect against dipterous leafminer (Liriomyza sp.) larvae. Leafminer species are controlled by Coragen, however certain coastal species of leafminer (L. huidabrensis and L. langei) are suppressed only. Suppression of silverleaf whitefly nymphs may also be achieved with the higher range of rates. Consult label for complete directions for use. Soil Shank Injection at Planting (Direct Seeded) Coragen should be injected approximately 2 inches directly below the seed line, so that developing roots of seedling vegetables come in contact with Coragen in the soil profile. As vegetable seeds germinate and develop as seedlings, Coragen is taken up through roots and translocated throughout plant tissues and growing points. Coragen provides plant protection as seedlings emerge from soil and as young plants develop. Placing Coragen deeper than 2 inches deep in the soil profile may delay or possibly prevent root uptake, resulting in less timely plant protection. In evaluations of various Coragen at-plant soil application methods in southwest vegetables, soil shank injections have provided the longest lasting protection against destructive lepidopterous worm pests. At-plant applications of Coragen may be applied in combination with labeled neonicotinoid products (e.g., imidacloprid) for improved control of silverleaf whiteflies and aphid. See tank-mix compatibility information in a later section of this Technical Update. Proper placement of soil shank injections is critical to root uptake and crop protection. Soil Shank Injection at Planting (Transplants) Soil shank injection of Coragen below transplants involves placement of a soil shank at approximately 1 /2 below the transplant root system. Placement below the transplant root system allows developing roots of a new transplant to come into contact with Coragen and translocate the active ingredient within the developing plant. When injected below transplant root systems, plant protection may not be immediate. Emerging seedling root systems must expand and grow into contact with Coragen for it to be taken up by roots and translocated throughout the plant for crop protection. 2

3 All photos on this page by J.L. Pacheco (DuPont) 3

4 In-Furrow Spray at Planting Coragen may be applied as an at-plant in-furrow spray directly into the seed line furrow. In-furrow sprays are mixed with water and applied directly in the seed line. Flat Fan Even nozzles (i.e., 8005E) are recommended to apply Coragen in a minimum of 20 gallons of water per acre, at 15 PSI. The spray nozzle can be oriented diagonally or vertically, depending on the distance from the nozzle tip to the bottom of the seed line furrow. In-furrow sprays should cover the width of the open seed line furrow. Reduced spray pressure prevents the spray from disturbing seed placement. Coragen applied as an in-furrow spray treatment must be followed by overhead sprinkler irrigation to move Coragen into the soil profile and root zone. As vegetable seeds germinate and emerge as seedlings, xylem mobile Coragen is taken up through plant roots and translocated throughout plant tissues and growing points, providing protection to seedlings and developing plants. Photo by T.L. Thomas (DuPont) Surface Band at Planting Coragen also may be applied as an at-plant banded spray, applied to the tops of planting beds directly over seed lines. When applied as a narrow surface band spray, apply using a 2-inch width band per seed line. Flat Fan Even nozzles (i.e. 8005E) are recommended to apply Coragen. Surface band applications require 1 /2 to 1 inch of overhead sprinkler irrigation, within 24 hours following application, to move Coragen into the root zone of germinating seedlings. As seedling vegetable plants emerge, Coragen is taken up by roots and translocated throughout plant tissues and growing points. This application method is most effective on shallow-seeded crops, such as lettuce. Note: At-plant surface band sprays may provide shorter length of control compared with other soil-applied methods. Weed growth on the surface of planting beds and/or disturbance or removal of Coragen treated soil by physical thinning operations may reduce availability of Coragen for root uptake. 4 Photo by M.J. Reid (DuPont) Photo by W.J. Steele (DuPont)

5 Photo by T.L. Thomas (DuPont) Photo by T.L. Thomas (DuPont) Photo by T.L. Thomas (DuPont) Transplant Water Treatment at Planting Vegetable transplants should be watered adequately before transplanting. Coragen may be applied as a transplant water treatment at planting. Ensure water volume is sufficient to thoroughly wet the root zone. Refer to label for rate and volume measurements and calculations. Photos by T.L. Thomas (DuPont) Drip Chemigation Coragen may be applied via drip chemigation in certain labeled crops. See product label for specific application methods allowed by crop. Accurate placement of drip lines relative to plant root systems is critical to the successful application of Coragen and effective plant protection. Buried drip lines should be located directly below seed lines or transplants, and within 2 inches of the plant root system for optimal uptake of Coragen to occur. Once applied, a time lag may occur between the drip chemigation of Coragen and uptake by roots and protection of treated plants. As a result, plants treated with Coragen may require a foliar treatment to provide timely protection of plants. Lepidopterous worm pests that feed on fruit in cucurbit crops (i.e., cabbage looper in melons) are typically controlled most effectively with foliar applications of Coragen. Photo by J.L. Pacheco (DuPont) 5

6 further Considerations for Soil and Drip Application There are several important factors to consider when using at-plant soil applications and drip chemigation: Determine target pests to be controlled. Consider root system types. Root systems at crop establishment occupy a smaller soil volume, requiring more precise product placement. Fiberous root systems occupy a larger soil volume allowing more flexibility in product placement. Apply Coragen in a manner that ensures the product is in the root zone. A drip application should not be used as a rescue treatment. Coragen applications via drip chemigation or as at-plant soil treatments should not be relied upon to provide protection of fruit, such as in vining crops. Foliar applications of Coragen should be applied instead to prevent feeding damage and/or scarring to fruit. Photos by J.L. Pacheco (DuPont) Considerations for Foliar Application Foliar applications of Coragen also are highly effective and may be preferred to soil applications in situations where: Soil applications may not be optimum to ensure placement in the root zone as described in this technical update. Damaging pest populations exist above the treatment threshold. A foliar application provides immediate coverage and contact activity to quickly protect fruit and plant materials from feeding damage. Photo by J.L. Pacheco (DuPont) Photo by J.L. Pacheco (DuPont) Photo by J.L. Pacheco (DuPont) 6

7 Photo by J.L. Pacheco (DuPont) Photo by J.L. Pacheco (DuPont) Coragen Compatibility with other Pesticides and Nutritional Sprays Coragen is compatible with most commonly used pesticides and nutritional sprays. However, since it is not possible to test all possible mixtures, the user should pre-test to ensure the physical compatibility and lack of phytotoxic effect of any proposed mixtures with Coragen. To determine the physical compatibility of Coragen with other products, use a jar test, as described below. Using a quart jar, add the proportionate amounts of the products to 1 quart of water. Add wettable powders and water-dispersible granular products first, then liquid flowables, and emulsifiable concentrates last. After thoroughly mixing, let stand at least 5 minutes. If the combination remains mixed or can be remixed readily, it is physically compatible. Once compatibility has been proven, use the same procedure for adding required ingredients to the injector tank. The crop safety of all potential tank mixes on all crops has not been tested. Confirm the safety to the target crop before applying any tank mixture not specified on the Coragen label. 7

8 Coragen Compatibility with Liquid Fertilizers Used at Planting Coragen may be mixed with certain liquid fertilizers for at-plant soil applications. Compatibility of Coragen + liquid fertilizer mixtures must always be determined before mixing by using a jar test. The following Coragen + various liquid fertilizer mixtures have been evaluated for compatibility (including for insecticide activity) and have been found to be compatible: UN / 8% sulfur Pop Up plus humic Coragen added to 1:1 mixtures of liquid fertilizers (above) + water with agitation resulted in good physical compatibility Phos X Coragen must be mixed with additional water, prior to mixing with a 1:1 mixture of Phos X + water to ensure compatibility. Coragen must not be mixed directly with pure liquid fertilizers. Coragen must not be pre-slurried with water and mixed directly with pure liquid fertilizers. Coragen must be mixed with fertilizer that has already been diluted with water at least 1:1 The following Coragen + liquid fertilizer mixtures have been evaluated for compatibility and have been found to be not compatible: liquid fertilizer Coragen was found to be not compatible with 1:1 mixtures of water, or premixed in the equivalent of 7.0 fluid ounces per acre in 20 GPA spray volume, prior to the addition of Coragen must not be mixed with liquid fertilizer applications. Physical Compatibility Studies with Liquid Fertilizers Conducted by DuPont Development (D.M. Tamayo) Yuma, Ariz. July 2, Phos X* UN32 CPS Helena /8 sulfur Pop-Up plus humic Coragen was physically compatible with these liquid fertilizers when agitated (fertilizers first mixed 1:1 with water) Note: Use only products that are labeled for at-plant soil applications. Always consult and follow product label use instructions. This reference guide is not intended as a substitute for the product label for the product(s) referenced herein. Product labels for the above product(s) contain important precautions, directions for use and product warranty and liability limitations that must be read before using the product. Applicators must be in possession of the product label(s) at the time of application. Always read and follow all label directions and precautions for use when using any pesticide alone or in tank mix combinations. The DuPont Oval Logo, DuPont, The miracles of science, Coragen and Rynaxypyr are trademarks or registered trademarks of DuPont or its affiliates. Copyright 2010 E.I. du Pont de Nemours and Company. All Rights Reserved. 10/10 Reorder No.: K-22909