Evaluation of Systemic Insecticides to Control of Asian Longhorned Beetle
Anoplophora glabripennis (ALB, Coleoptera: Cerambycidae), was discovered killing trees in New York in 1996. It had been inadvertently introduced into North America probably in solid wood packing material associated with imports from eastern China or Korea where it is native. Infestations have since been found in Illinois, New Jersey, Massachusetts, Ohio, and Ontario, Canada. Because of its wide host range and its ability to attack and eventually kill apparently healthy trees, ALB has the potential to cause serious economic and ecological damage nationwide. Therefore, eradication programs under the direction of the USDA Animal and Plant Health Inspection Service (APHIS) and the Canadian Food Inspection Agency (CFIA) have been underway at all North American infested sites since their discovery. As part of the eradication program, surveys are conducted to locate infested trees which are then are cut down and destroyed. Other control methods are needed to aid in eradication and to form an integrated management program in the event eradication fails. The use of systemic insecticides may prove useful in controlling Asian longhorned beetle adults during maturation twig feeding and larvae feeding inside the tree.
We evaluated various doses of the systemic insecticides, azadirachtin, emamectin benzoate, imidacloprid, and thiacloprid for control of A. glabripennis in naturally infested elms (Ulmus), poplars (Populus), and willows (Salix) in China. Trees were injected with systemic tree injection tubes (STITs) or Mauget capsules (J. J. Mauget, Co.) Dead adults were collected at the base of each tree for several weeks after injection, and trees were felled and dissected to assess larval mortality up to one year after injection.
In the laboratory, we evaluated the toxicity of systemic insecticides to ALB adults and ALB and cottonwood borer larvae (CWB) Plectrodera scalator (F.) (Coleoptera: Cerambycidae), a closely related native cerambycid. ALB adults were fed maple twigs that were treated with a high or low dose of imidacloprid. Mortality and feeding were observed daily until all adults had died. Larvae of both cerambycid species were fed artificial diet with various doses of azadirachtin or imidacloprid for 14 weeks. The larvae were transferred to fresh treated diet each week at which time mortality was assessed, amount of feeding was determined, and larvae were weighed.
Injecting ALB infested trees with imidacloprid can result in significant mortality of adults during maturation feeding on leaves and twigs and of all life stages feeding within infested trees. Imidacloprid is translocated rapidly in infested trees and is persistent at lethal levels for several months. Although, injection with imidacloprid does not provide complete control of ALB, systemic insecticides may prove useful as part of an integrated eradication or management program. The delivery of high and sustained insecticide concentrations will be needed to overcome the antifeedant effects and lengthy lethal time for both larvae and adults exposed to these insecticides.
Significantly more dead ALBadults were found beneath elm, poplar, and willow trees treated with imidacloprid or thiacloprid compared to control trees. Four months after injection, the density of live ALBwas significantly reduced in poplar trees treated with imidacloprid and in willow trees treated with imidacloprid or emamectin benzoate compared to controls. Similarly, percent mortality of all life stages of ALBfeeding within trees was significantly higher on poplar trees 4 months after injection with imidacloprid and on elms and poplars 9 months after injection with imidacloprid compared to control trees. Imidacloprid residue levels in leaves and twigs collected at various times from 1 day to 9 mo after injection ranged from 0.27 to 0.46 ppm.
In the laboratory, ALB adult mortality reached 100% after 13 days on twigs treated with 150 ppm imidacloprid and after 20 days on twigs treated with 15 ppm imidacloprid. There was no visible feeding by ALB adults on twigs treated at the higher imidacloprid rate, and feeding was significantly reduced for adults placed on twigs treated at the low imidacloprid rate when compared to adults on untreated twigs. Both imidacloprid and azadiracthin had strong antifeedant effects, which resulted in larval weight loss. For ALB the highest larval mortality at the end of the bioassay was 60% for larvae fed artificial diet treated with azadirachtin (50 ppm) or imidacloprid (1.6 ppm). For CWBthe highest larval mortality at the end of the bioassay was 100% for larvae fed artificial diet treated with azadirachtin (50 ppm) or imidacloprid (160 ppm). At 14 weeks, the LC50 values for CWBwere 1.58 ppm and 1.78 ppm for azadirachtin and imidacloprid, respectively.
Poland, Therese M.; Haack, Robert A.; Petrice, Toby R.; Miller, Deborah L.; Bauer, Leah S.; Gao, Ruitong. 2006. Field Evaluations of Systemic Insecticides for Control of Anoplophora glabripennis (Coleoptera: Cerambycidae) in China. J. Econ. Entomol. 99(2): 383-392 (2006).
Poland, Therese M.; Haack, Robert A.; Petrice, Toby R.; Miller, Deborah L.; Bauer, Leah S.. 2006. Laboratory Evaluation of the Toxicity of Systemic Insecticides for Control of Anoplophora glabripennis and Plectrodera scalator (Coleoptera: Cerambycidae). J. Econ. Entomol. 99(1): 85-93 (2006).
- Therese M. Poland, USDA Forest Service - Northern Research Station Research Entomologist
- Robert A. Haack, USDA Forest Service - Northern Research Station Research Entomologist (Retired)
- Toby R. Petrice, USDA Forest Service - Northern Research Station Entomolgist
- Leah S. Bauer, USDA Forest Service - Northern Research Station Research Entomologist
- Deborah L. Miller, USDA Forest Service - Northern Research Station Entomologist
- Ruitong Gao, Chinese Academy of Forestry
Last Modified: 07/13/2017