A-

Forest 4t 1 + Awareness

technical reference insecticide NUCLEAR POLYHEDROSIS VIRUSES

4. Forestry Commercial Products: • BASIC FACTS Name Manufacturer Reg. Target Guarantee No. Under PCPA" 1. Common Name: Lecontvirus F.P.M.I." 17824 Red-headed 5 x 103 NPVs (Nuclear Polyhedrosis Viruses) pinesawfly PIBs/ml Virtuss F.P.M.I. 17786 Douglas-fir 20x109 tussock PIBs/ml 2. Biological Classification: moth TM BioControl-1c U.S.Forest 19293 Douglas-fir 70x106 Baculovirus; family Baculoviridae. Service tussock A.u./ga subgroup A. moth 0 Forest Pest Management Institute. b Pest Control Products Act c TM BioControl-1 is an NPV registered in Canada for the control of the 3. Active Ingredient: Douglas-fir tussock moth. This product is produced in the United States and is identical to the Canadian product called Virtuss. The particles which initiate infection in the l!The weight of TM BioControl-1 powder to treat each hectare is determined by bioassay and varies with each lot. Activity units, (A.u.), are an expression are called virions. These rod-shaped structures of the LDr,o dosage, and are usually expressed as potency; the number are embedded in proteinaceous crystal bodies of A.u 'g of virus preparation. (Marignoni and Iwai, 1978). called polyhedra, or more commonly, polyhedral inclusion bodies, (PIBs). The number of virions 5. Physical and Chemical Properties: found in PIBs vary greatly among viruses. Production: NPVs are produced in living insect Preparations of NPVs can be standardized, in part, larvae. Healthy larvae are infected with NPV and by determining the number of PIBs per unit harvested after the virus infection has had time to measure of the mixture. spread throughout the larvae. This usually takes from 10 to 12 days. Polyhedra can be purified from these larvae, or more often, the whole of the infected larva is freeze dried and ground to a fine powder. This powder contains NPVs. Appearance: Purified polyhedra are white when in aqueous suspension. Ground larvae are a grey powder. Odour: Slight and characteristic. Stability: Purified polyhedra and powders can be r kept for several years with little loss of activity. It is not recommended to keep NPVs in the formulated state for more than 2 months. Solubility: Soluble in water and oil formulations Magnification 45920X with pH between 6 and 8. 6. History: Insect viruses were discovered in the 19th century, Rates for aerial application and have been known to cause high mortality Larval Rate of lecontvirus Water* Total instar per hectare emitted in insect populations. In Canada, an NPV was first volume used to control a forest pest in 1950, when out per breaks of the European spruce , Gi/pinea hectare hercinae (Hartig), became severe (Bird and Milli- Burke, 1961). Many insect are known to be litres PIB Litres Litres susceptible to NPVs, but because of the complex Plantations 1st & 2nd 10 5x109 9.4 9.4 (5 billion nature of virus-insect relationships, only a few polyhedral in NPVs have been found suitable to be developed clusion bodies) as biological insecticides. 3rd & 4th 20 10x109 9.4 9.4 (10 billion polyhedral in 7. Insecticide Spectrum and Mode of Action: clusion bodies) NPVs are very host specific and replicate in only Rates for ground application one, or in a few related host species (Vaughn et al., 1977). Polyhedra must be eaten by the insect Larval Rate of lecontvirus Water* Total instar per hectare emitted larvae to be effective and cause death. Once volume polyhedra are injested, they are dissolved by the per alkaline pH of the insect gut. This releases hectare virions into the stomach which penetrate the cells Milli- of the gut and initiate cellular infection. Polyhedra litres PIB Litres Litres Plantations 1st & 2nd 10 5x109 20 20 are produced in these infected cells, and within (5 billion 10 to 12 days the larva dies of NPV infection. As the polyhedral in larva disintegrates, these newly formed polyhedra clusion bodies) are released into the forest and are available to 3rd & 4th 20 10x109 20 20 infect other of the same species. (10 billion polyhedral in clusion bodies)

REGISTERED USES AND APPLICATION TECHNOLOGY b) Virtuss. Virtuss is a freeze dried powder and suspensions are possible in both aqueous and emulsifiable 1. Registered Uses for Forestry: oil. However, for aerial applications, the emulsifi The NPVs registered in Canada are for restricted able oil is recommended. use and can only be applied under the direct supervision of Federal or Provincial Forestry Rates for aerial application Service personnel. These products are registered Rate of virtuss Gelled oil Water* Total for Forest management use (>500 ha), and Wood per hectare vehicle emitted lands management (<500 ha). May be applied Volume per by ground or aerial spraying. hectare

Grams PIB Litres 2. Operational Details: Forest 12.5 2.5x10" 25% total 75% 9.4 (250 billion volume total Potential users are referred to the official label, polyhedral in volume local/provincial laws and regulations, federal and clusion bodies] provincial regulatory officials for details neces sary to plan specific projects. The timing of the Virtuss may also be applied by ground equipment application will depend on the stage of develop to woodlands, along right-of-ways, in tree ment of the target insect. nurseries or seed orchards and in treed areas • Timing and Dosage: of less than half a hectare where high valued or Product Timing Dosage ornamental trees may be attacked. Lecontvirus 1st and 2nd 5x109PIBs/ha instars Rates for ground application Lecontvirus 3rd and 4th 10 x 109PIBs/ha Rate of virtuss Water* Total instars per hectare emitted Virtuss 1st and 2nd 2.5x10" PIBs/ha Volume instars per hectare TM BioControl-1 1st and 2nd 2.68x109A.u./ha instars Grams PIB Litres Litres Treed areas 12.5 2.5x10" 1000 1000 Mixing: under0.5 ha (250 billion total polyhedral a) Lecontvirus inclusion bodies! Lecontvirus is usually supplied as a suspension in •Chlorinated or highly alkaline water should not be used in tank mixes. Tank emulsifiable oil which is diluted in water, as out mix pH should be between 6.0 and 7.2. pH can be adjusted by adding NaOH lined below, for either aerial or ground application. (sodium hydroxide) if it is below 6.0. c) TM BioControl-1. TM Bio-Control-1 is a freeze dried powder and • SAFETY suspensions in water or emulsifiable oil can be applied in aerial application. 1. Handling: Rates for aerial application emulsifiable oil Care must be exercised when handling an insecti Rate of TM Biocon- Abbott Water* Total trol-1 per hectare labora emitted cide, although NPVs are environmentally safe, tories volume some additives to the spray formulation may be gelled oil per harmful at concentrated levels. vehicle hectare • Wear rubber boots, rubber suit or apron, rubber Grams Activity Units Litres gloves, respirator, goggles and cap or hat when Forest 3.5-7.0 2 681 x 109 25% total 75% 9,1 mixing/processing concentrates. volume total volume • Contaminated clothing should be removed and washed before use. • If spilled on skin wash immediately with soap In water and water.

Rate of TM Biocon- Molasses Water* Total • Wash hands before smoking or eating. trol-1 per hectare emitted • Keep unauthorized and unprotected persons out volume of loading or mixing zones. per hectare Grams Activity Units Litres 2. Product Precautions: Forest 3.5-7.0 2 681 x 10s 25% total 75% 9.4 volume total Avoid contact with skin, eyes or clothing. volume Avoid inhalation. Do not contaminate food or any body of water. TM BioControl may be applied by ground equip ment to woodlands, along right-of-ways, in tree nurseries or seed orchards and in treed areas 3. Disposal and Storage: of less than half a hectare where high valued or ornamental trees may be attacked. Do not store at temperatures above 32° C. Do not reuse empty container. Rates for ground application Destroy or discard empty container in a safe place, according to government disposal Rate of TM BioCon- Water- Total trol-1 per hectare emitted regulations. Volume per hectare 4. Medical Treatment: Grams A.u. Litres Litres • Skin and eye irritant. Treed areas 3.5-7.0 2.681 x 109 1000 1000 under 0.5 ha (2.681 billion A.u ) In case of contact, immediately flush eyes or skin with plenty of fresh water. Get medical attention Note: You can add 1% colorant for checking methods. if irritation persists, or if swallowed in any large amount.

• EFFECTS ON BIOTA • QUESTIONS AND ANSWERS

1. Insects Controlled:

NPVs are extremely host specific. Lecontvirus is Q. Is it safe to use nuclear polyhedrosis viruses? only effective against the red-headed pine saw- A. NPVs are naturally-occurring pathogens found fly, lecontei (Fitch). Virtuss and TM in most insect populations. As such they are BioControl-1 are registered for use against the already present in the environment and persist to Douglas-fir tussock moth, Orgyia pseudotsugata regulate insect populations. Often the quantity (McDunnough). of NPVs present is too low to cause any noticeable reduction in the insect population. Introduction 2. Effects on Non-Targets: of NPVs into these populations serves only to augment the quantities of NPVs naturally present, NPVs are naturally-occurring pathogens found in at levels which will cause widespread disease most insect populations. They present no hazard and insect mortality. No other is affected to the environment and non-target organisms. by this technique. Extensive safety testing involving several species of birds, mammals and non-target invertebrates Q. Can NPVs infect vertebrates? have been conducted and these results are A. NPVs are a very special type of virus which included in the documentation for registration infects only certain insect species. No measur of each NPV. Copies of these reports can be able virus replication has been detected in non- obtained on request from FPMI. Doller (1985) target organisms like birds, fish and mammals provides an excellent review on the safety of (Doller, 1985). However, biologically active virus insect viruses. can be found in the faeces of some , for example, birds, which indicates that they are 2. References in the Text: able to spread the NPV throughout the forest Bird, F.T. and J.M. Burke, 1961. Artifically dissemin (Entwistleetal., 1977). ated virus as a factor controlling the European Q. How long do NPVs remain in the forest? spruce sawfly, Diprion hercyniae (Htg.) in central A. NPVs can persist up to 40 years in the forest New Brunswick. Can. entomol. 93:228-238. soil (Thompson et al., 1981). Research has indi Doller, G., 1985. The safety ofinsect viruses as cated that infectious polyhedra are detected on biological control agents, in Viral insecticides foliage for up to 3 years after insect larvae have for biological control. (K. Maramorosch and been killed by this disease. Although NPV is short K. Sherman, eds.) Academic Press, New York. lived on foliage, it can persist on bark for long periods and be transferred to foliage by rainfall Entwistle, PR, P.H.W. Adams and H.F. Evans, 1977. (Kaupp, 1983). Epizootiology ofa nuclearpolyhedrosis virus in European pine sawfly, Gilpinia hercyniae: Q. Are there any drawbacks to using NPVs? The status ofbirds as dispersal agents of the virus A. Yes, there are some minor drawbacks to the during the larval season. J. Invertebr. Pathol. use of NPVs in forest insect control. Because the 29:354-360. NPV takes up to 2 weeks to kill the larvae, some defoliation must be expected. Also, under high Kaupp. W.J.,1983. The persistence ofNeodiprion population levels, the NPV is not as efficient a sertifer (HymenopteraDiprionidae) nuclear control as are some chemicals because of the polyhedrosis on Pinus contorta foliage. Can. mode of action, delay in insect death and limited Entomol. 115,869-873. numbers of polyhedra available to cause infection. Martignoni, M.E. and P.J. Iwai, 1978. Activity Q. Are there any other biological insecticides standardization of technicalpreparations of like Lecontvirus, Virtuss and TM BioControl-1 Douglas-fir tussock mothBacu\ov\rus. J. Econ. available? Entomol. 71:473-476. A. An NPV product called Sertifervirus, is currently undergoing review for registration in Thompson, C.G., D.W. Scott and B.E. Wickman, 1981. Long-term persistence ofthe nuclear Canada. This NPV controls the European pine polyhedrosis virus ofthe Douglas-fir tussock sawfly, Neodiprion sertifer (Geoffrey). Presently, F.P.M.I. is developing an NPV which infects the moth, Orgyia pseudotsugata (: gypsy moth, Lymantria dispar (L.)and it is hoped Lymantriidae), in forest soil. Environ. Entomol. that this product will be registered for forestry 10:254-255. use in the near future. Vaughn, J.L., R.H. Goodwin, G.J. Tompkins and Q. Have NPVs been used operationally in P.M. McCawley,1977. The establishment oftwo the past? cell lines from the insectSpodoptera frugiperda (LepidopteraiNoctuidae). In Vitro 13: 213-217. A. In the United States, TM BioControl-1 has been used operationally since 1976 to control out breaks of Douglas-fir tussock moth, 0. pseudos- 3. Other References: ugata. Another product called Gypchek, the NPV infecting the gypsy moth, L. dispar, has been in Cunningham, J.C. 1982. Field trials with use operationally since 1979. baculoviruses in Microbial and viral pesticides. In Canada, Virtuss and TM BioControl-1 have (E. Kurstak ed.) Marcel Dekker, New York. never been used operationally, however extensive research has indicated that both these prepara tions are very efficacious. Presently, Virtuss and TM BioControl-1 are being stockpiled in anticipa While the information in this Technical Reference tion of the next outbreak of Douglas-fir tussock has been compiled from source materials moth, 0. pseudotsugata. Lecontvirus, the NPV available at the time of publication, the authors infecting the red-headed pine sawfly, N. lecontei, disclaim all liability with respect thereto. is in operational use by Provincial authorities. Additional copies are available in English and in French from the Canadian Pulp and Paper Association • REFERENCES Forest Protection Committee Sun Life Building, 23rd Floor 1155 Metcalfe Street 1. Addresses of Manufacturers: Montreal, Quebec Forest Pest Management Institute, Canada H3B 2X9 Canadian Forestry Service, Tel. (514) 866-6621 P.O. Box 490, or from SaultSte. Marie, Ontario, The Forest Pest Management Institute Canada P6A5M7 Canadian Forestry Service P.O. Box 490 U.S. Forest Service, USDA, Sault Ste. Marie, Ontario 14th and Independence Avenues, Canada P6A 5M7 Washington, D.C. Tel. (705) 949-9461 s/f USA 27 709