2006 Annual Report
The emerald ash borer is but one of many non-indigenous species that recently have become established in the United States. Development of biological control technologies for these exotic pests is also critically needed. Such research requires quarantine facilities, but many state and federal biological control workers do not have a quarantine facility, but require quarantine services for importation of promising biological control agents.
In order to address these problems, this CRIS has the following objectives: (1) Conduct explorations for natural enemies of the emerald ash borer (includes foreign exploration in the Far East as well as a search for native natural enemies of indigenous buprestid beetles), choose suitable investigation areas, inventory natural enemies attacking target pest, investigate the structure of the enemy complex, and conduct field studies of their impact on the target pest. (2) Perform bioecological studies on promising natural enemies discovered including studies on life history and behavior, host specificity (Asiatic species), synchronization with the pest, physiological tolerance to different climatic factors, and establishment of priorities in utilization of promising species based upon their biological characteristics. (3) Provide quarantine services for beneficial insects including quarantine handling of natural enemies of high priority plant pests for other in-house projects (Asian longhorned beetle, soybean aphid, Russian wheat aphid, lygus bugs, brown marmorated stinkbug) and pass-thru services for state and federal agencies.
The work is relevant not only to regulatory and other government agencies, but other stakeholder groups as well: nursery owners, foresters, land managers, conservationists and manufacturers of wood products (baseball bats, tool handles, etc.). Homeowners could be greatly benefited, because ash comprises about 20% of the shade trees in the Midwest, and it is estimated that takedown costs for dead trees has already exceeded $1 billion.
The research relates to National Program 304, Crop Protection and Quarantine, which seeks to reduce populations of pest insects to below economic threshold levels by developing environmentally compatible methods that are based on knowledge of the biology and ecology of the pest and its natural enemies. Specific components of NP 304 addressed are 2 Biology of pests and natural enemies, 3 Pest enemy interactions, 5 Pest control strategies, and 6 Area wide pest suppression.
Objective 1: Exploration for and discovery of natural enemies of emerald ash borer 111 Foreign exploration and collection of natural enemies. Begin explorations in Asia for exotic natural enemies. 121 Domestic search for natural enemies. Begin explorations in U.S. for native natural enemies.
Objective 2: Bioecological studies on promising natural enemies of emerald ash borer 211 Prioritization and importation of candidate natural enemies. Establish laboratory colony of EAB. Import Spathius and Tetrastichus. 221 Host specificity tests on candidate natural enemy species. Develop list of nontarget species for testing. 231 Studies of native parasitoids of buprestid beetles. Complete literature search and parasite-host catalog. Begin surveys.
Objective 3 Provide quarantine services to other agencies: 311 Conduct Passthrough quarantine handling. Receive, identity, and ship organisms to cooperators 321 Documentation and general maintenance, security, and equipment. Review and update records; inspect, repair or upgrade facility, physical plant.
Year 2 (FY 2007)
Objective 1 Exploration for and discovery of natural enemies of emerald ash borer 112 Foreign exploration and collection of natural enemies. Continue explorations in Asia 122 Domestic search for natural enemies. Continue explorations in U.S.
Objective 2 Bioecological studies on promising natural enemies of emerald ash borer 212 Prioritization and importation of candidate natural enemies. Import any additional promising candidates. 222 Host specificity tests on candidate natural enemy species. Life history and host range studies on promising candidate species. 232 Studies of native parasitoids of buprestid beetles. Continue surveys. Begin trials with EAB.
Objective 3 Provide quarantine services to other agencies: 312 Conduct Pass-through quarantine handling. Receive, identity, and ship organisms to cooperators 322 Documentation and general maintenance, security, and equipment. Review and update records; inspect, repair or upgrade facility, physical plant.
Year 3 (FY 2008)
Objective 1 Exploration for and discovery of natural enemies of emerald ash borer 113 Foreign exploration and collection of natural enemies. Finish explorations in Asia 123 Domestic search for natural enemies. Finish explorations in U.S.
Objective 2 Bioecological studies on promising natural enemies of emerald ash borer 213 Prioritization and importation of candidate natural enemies. Finish importations. 223 Host specificity tests on candidate natural enemy species. Host range studies on promising candidate species. EA on 1st species 233 Studies of native parasitoids of buprestid beetles. Complete surveys. Continue trials with EAB 243 Mass rearing, release and evaluation of natural enemies. Develop mass rearing technology for most promising candidate species.
Objective 3 Provide quarantine services to other agencies: 313 Conduct Passthrough quarantine handling. Receive, identity, and ship organisms to cooperators 323 Documentation and general maintenance, security, and equipment. Review and update records; inspect, repair or upgrade facility, physical plant.
Year 4 (FY 2009)
Objective 1 Exploration for and discovery of natural enemies of emerald ash borer 114 Foreign exploration and collection of natural enemies. Completed 124 Domestic search for natural enemies. Completed
Objective 2 Bioecological studies on promising natural enemies of emerald ash borer 214 Prioritization and importation of candidate natural enemies. Completed 224 Host specificity tests on candidate natural enemy species. Host range studies on promising candidate species. EA on 2nd species 234 Studies of native parasitoids of buprestid beetles. Rank most promising North American species found 244 Mass rearing, release and evaluation of natural enemies. Develop mass rearing technology for 2nd promising candidate species. Release any species cleared for release
Objective 3 Provide quarantine services to other agencies: 314 Conduct Passthrough quarantine handling. Receive, identity, and ship organisms to cooperators 324 Documentation and general maintenance, security, and equipment. Review and update records; inspect, repair or upgrade facility, physical plant.
Year 5 (FY 2010)
Objective 1 Exploration for and discovery of natural enemies of emerald ash borer 115 Foreign exploration and collection of natural enemies. Completed 125 Domestic search for natural enemies. Completed
Objective 2 Bioecological studies on promising natural enemies of emerald ash borer 215 Prioritization and importation of candidate natural enemies. Completed 225 Host specificity tests on candidate natural enemy species. Host range studies on promising candidate species. EA on 3rd species 235 Studies of native parasitoids of buprestid beetles. Completed 245 Mass rearing, release and evaluation of natural enemies. Release any species cleared for release; monitor at release sites.
Objective 3 Provide quarantine services to other agencies: 315 Conduct Passthrough quarantine handling. Receive, identity, and ship organisms to cooperators 325 Documentation and general maintenance, security, and equipment. Review and update records; inspect, repair or upgrade facility, physical plant.
Objective 2 Because some North American parasitoids might adapt to EAB, we have continued studies started during the previous CRIS (1926 22000 014 00D) cycle on parasitoids attacking buprestid beetles in Pennsylvania and Delaware. Two approaches are being used: (1) girdling preferred host plants (white, green and black ash for EAB and maples, poplars, willows and others for ALB), then felling them at intervals thereafter, and (2) taking infested material from sites with recent logging debris or blow-downs. In the latter sites, we captured foraging females of parasitic wasps with an insect net for laboratory study. Bolts are taken from the field to an unheated insectary. Bolt ends are waxed to inhibit desiccation prior to storage in ventilated trash cans for emergence of borers and their parasitoids. To date, far more long horn beetles (family Cerambycidae) than jewel beetles (family Buprestidae) have emerged, but we anticipate more jewel beetles emerging in the spring of 2007. A number of parasitoids have emerged, which are in the process of being identified.
This CRIS project replaced 1926 22000 014 00D which had been focused primarily on biological control of gypsy moth. In 2006, some work was conducted but was limited to lines of research needed to fulfill commitments to organizations made earlier: (1) Cooperative survey for natural enemies of gypsy moth in Wisconsin (second year of 2 year study); (2) SCA #58 1926 2 F158 (CRIS 1926 22000 020 01S: Collection and ecology of gypsy moth parasites in Poland) with the Forest Research Institute in Warsaw, Poland; (3) SCA #58 1926 5 506 (CRIS 1926 22000 020 02R: Bracovirus evolution: comparative analysis of multiple proviral and viral segment sequences) with The Institute for Genomics Research, Rockville, MD. These have been reported under 1926 22000 014 00D.
1926-22000-020-01S: This report serves to document research conducted under a specific cooperative agreement between ARS and the Forest Research Institute in Warsaw, Poland. The project objectives are (1) to collect and study parasitoids of the gypsy moth for biological control, (2) to obtain living material of selected species for host range studies, (3) to compare levels of gypsy moth parasitism on different plant species, and (4) to compare levels of parasitism in natural and artificial populations of the gypsy moth.
During 2006, analyses were completed on field studies conducted in Poland during 2005 on the gypsy moth, LYMANTRIA DISPAR and its parasitoids. The objectives were as follows: (1) to collect gypsy moth parasitoids (BLEPHARIPA SCHINERI, PHOBOCAMPE UNICINCTA, COTESIA MELANOSCELUS, GLYPTAPANTELES LIPARIDIS and APHANTORHAPHOPSIS SAMARENSIS); (2) compare levels of parasitism at different phases of gypsy moth population dynamics; (3) compare levels of gypsy moth parasitism on different plant species; (4) make collections of potential alternative hosts to see if they are attacked by B. SCHINERI; and (5) conduct studies on interspecific competition among larval parasitoids of gypsy moth.
Objective 1 Parasitoid collections and shipments to BIIR. At the end of the 2005 season, 360 specimens of BLEPHARIPA spp. and a number of P. UNICINCTA and C. MELANOSCELUS were shipped to BIIR.
Objective 2 Incidence of parasitism and disease at different phases of the gypsy moth population cycle. Data were collected in plots at three localities where gypsy moth populations were in different phases of the cycle (gradation). In the Honczarowska plot (post outbreak phase), there was high mortality of gypsy moth larvae ranging from 62% in the first sample to 99% in the third sample. In second and fourth samples mortality was above 90%. As one could expect at the post outbreak phase and similarly to the results obtained at the Barwik plot in 2004 (when it was in post outbreak phase), the main cause of larval death was virus. Virus killed a majority of larvae collected on 22 May (61%) and on 3 June (86%). Larval mortality on birch (BETULA spp.) and oak (QUERCUS spp.) due to virus was higher than on hazelnut (CORYLUS spp.) and alder (ALNUS spp). Parasitism in both samples was low and did not exceed 10%. In mid June the mortality caused by virus and parasitoids was at the similar level (49 and 50% respectively). Virus was still the main cause of larval death on hazelnut and birch, whereas on oak and alder, its effect was weaker and parasitoids were the dominant mortality factor. In early July parasitoids caused 58% mortality. Parasitoids emerging from the gypsy moth larvae and pupae belonged to 5 families: Chalcididae (BRACHYMERIA sp.), Braconidae (C. MELANOSCELUS and G. LIPARIDIS), Ichneumonidae (P. UNICINCTA), Tachinidae (ACTIA PILIPENNIS, P. SILVESTRIS, BLEPHARIPA spp., COMPSILURA CONCINNATA, BLONDELIA NIGRIPES, 1 species of tribe Siphonini) and Sarcophagidae. Dominant species were: P. SILVESTRIS (max. 40%), BLEPHARIPA spp. (max. 24%) and sarcophagids 15%. Parasitism by other species was < 2%.
In the Barwik plot (year 1 of latency phase) parasitism was 25, 64 and 43% on 3 June, 22 June and 6 July, respectively. The species composition of parasitoids slightly differed from that in the Honczarowska plot. In the Barwik plot, there were no specimens of BRACHYMERIA sp., A. PILIPENNIS or sarcophagids, but two species of Ichneumonidae (CASINARIA TENUIVENTRIS and HYPOSOTER sp.), the tachinid A. SAMARENSIS and the braconid METEORUS PULCHICORNIS. The dominant species were: C. MELANOSCELUS max. 33% and P. UNICINCTA max. 11%. Other parasitoids with attack rates >5% were: A. SAMARENSIS and P. SILVESTRIS (both max. 7,5%) and BLEPHARIPA spp. (max. 7%).
In the Kopciowe plot (in 10th year of latency phase), mortality of gypsy moth caused by parasitoids was 14, 55 and 66% in samples I, II and III, respectively. The species composition was quite similar to those in other plots. In comparison to the Barwik plot the changes were as follows:.
Objective 3 Effect of tree species on parasitism of gypsy moth. Statistical analysis of parasitism by P.SILVESTRIS and BLEPHARIPA spp. in the Honczarowska plot did not reveal any significant differences in parasitism by these species on different tree species, although P.SILVESTRIS was slightly more abundant on oak, and BLEPHARIPA spp. on alder. Among less abundant parasitoids, P. UNICINCTA seems to prefer host larvae on alder, and C. MELANOSCELUS those on birch. In the Barwik plot, a significant difference was found only in the parasitism by C. MELANOSCELUS. Gypsy moth larvae on hazelnut were substantially less attacked by this species than those feeding on willow, oak or alder. No other species analyzed (A. SAMARENSIS, P. UNICINCTA and P. SILVESTRIS) showed any significant preference, although unlike C. MELANOSCELUS, all of them were more abundant on hazelnut. Among less abundant parasitoids, C. TENUIVENTRIS seems to prefer larvae on willow (SALIX). In the Kopciowe plot, there were significant differences in the attack rate by dominant parasitoids on different tree species. COTESIA MELANOSCELUS attacked slightly less larvae on hazelnut that confirms finding in the Barwik plot. In the Kopciowe plot, C. TENUIVENTRIS slightly preferred birch (this tree species was not studied in the Barwik plot), A. SAMARENSIS and BLEPHARIPA spp. alder, and P. SILVESTRIS hazelnut. BLEPHARIPA spp. were the least abundant on birch, and P. silvestris on alder. As in the Honczarowska plot, the attack rate by P. UNICINCTA was slightly higher on alder than on other tree species.
Objective 4 Host range of gypsy moth parasitoids. The purpose of this study was to obtain information on the host range of BLEPHARIPA SCHINERI and other gypsy moth parasitoids under natural conditions. The larvae of six other moths/butterflies were collected (1 6 larvae per species) in 2005 from all study plots to examine their parasitism. They were: drinker moth, EUTHRIX POTATORIA (Lasiocampidae); rusty tussock moth, ORGYIA ANTIQUA, yellow tail moth, EUPROCTIS SIMILIS; satin moth, LEUCOMA SALICIS (Lymantriidae); magpie moth, ABRAXAS GROSSULARIATA (Geometridae); and map butterfly, ARASCHNIA LEVANA (Nymphalidae). No BLEPHARIPA spp. emerged from any larvae. A puparium similar to BLEPHARIPA was obtained from drinker moth, however it desiccated, and no fly emerged; thus it was not possible to determine the parasitoid species. From magpie moth we obtained P. SILVESTRIS, from rusty tussock moth A. SAMARENSIS, from yellow tail moth P. SILVESTRIS and ALEIODES sp. (Braconidae), determined by J. Hilszcza¿ski), from satin moth P. SILVESTRIS, C. CONCINNATA, METEORUS sp., and CARCELIA sp. (determined by C. Bystrowski).
Objective 5 Interspecific competition between larval parasitoids. Among all gypsy moth collected in three study plots, no cases of multiparasitism by P. UNICINCTA with any other parasitoid species were observed. In the Honczarowska plot there was also no cases of multiparasitism by COTESIA MELANOSCELUS with other parasitoids. In the Barwik plot there was one larva that yielded C. MELANOSCELUS and A. SAMARENSIS, and one larva that yielded C. MELANOSCELUS and C. CONCINNATA (in the sample on 22 June). The cases of multiparasitism by C. MELANOSCELUS and A. SAMARENSIS were more frequent (6 larvae in the sample on 22 June and 5 larvae in the sample on 6 July) in the Kopciowe plot. There were no observations of multiparasitism by P. UNICINCTA and C. MELANOSCELUS. Dissections of 20 larvae that yielded P. UNICINCTA did not reveal any undeveloped parasitoids inside. In most cases the remains of larvae that yielded this parasitoid species consisted only of head capsule and skin. Among 21 dissected larvae yielding C. MELANOSCELUS, 5 larvae (24%) had one up to three undeveloped parasitoids of undetermined species.
The possibility of successful multiparasitism of the gypsy moth larva by C. MELANOSCELUS and C. CONCINNATA was confirmed earlier by Weseloh (1983), who showed that in host larvae parasitized by both species, neither parasitoid consistently destroyed the other, and both parasites emerged from 11% of the hosts. The relationship between C. MELANOSCELUS and A. SAMARENSIS might be quite similar. There is no available information on interspecific competition between P. UNICINCTA and C. MELANOSCELUS, however the maximal use of a host larva as a source of food by a larva of P. UNICINCTA leaving only the cuticle of the gypsy moth suggests that the possibility for successful multiparasitism by these species is rather small.
1926-22000-020-02R: This report serves to document research conducted under a reimbursable agreement between ARS and The Institute for Genomic Research, with the collaboration of the ARS Insect Biological Control Laboratory, Beltsville, MD. The primary funding source is the USDA National Research Initiative Competitive Grants Program. Braconid wasps are important in the biological control of many insect pests. Many species of braconid wasps are endoparasites that contain proviral polydnaviruses that enable the wasp to overcome host immune responses and successfully complete its development. Constructing BAC libraries and sequencing the viral DNA of polydnaviruses associated with several different braconids will increase our understanding of the genetic and physiological interactions among polydnaviruses, parasites and their pest insect hosts and enable the development of innovative biological strategies for managing pest insects.
The objectives of this project (started 12/30/04) were to (1) Obtain and mass rear the braconid gypsy moth parasitoids GLYPTAPANTELES INDIENSIS Marsh, G. FLAVICOXIS Marsh, and COTESIA MELANOSCELUS (Ratzeburg). (2) Provide the project with material needed to establish BAC libraries for G. INDIENSIS and C. MELANOSCELUS. (3) Provide the project with material needed to do polydnavirus sequences for G. FLAVICOXIS.
With the help of Dr. Gujjanadu Ramaseshiah, who made collections of Indian Gypsy moth, LYMANTRIA OBFUSCATA Walker, in India, we established laboratory cultures of G. INDIENSIS Marsh and G. FLAVICOXIS Marsh in 2004. Attempts to start a culture of COTESIA MELANOSCELUS were unsuccessful. The work with GLYPTAPANTELES spp. has proceeded well, and with the assistance of the ARS Lab in Beltsville, we have provided over one (1) gram of wasp larvae of each species to The Institute of Genomic Research for the establishment of BAC libraries. In addition, we have provided adults of both GLYPTAPANTELES spp. to Dr. Gundersen Rindal for polydnavirus sequencing. Cultures of both species are being maintained through the life of the project (which expires 08/31/06) to generate additional viral samples as needed on an ad hoc basis to validate segment sequences. Over twenty generations of each species have been reared since the project started in 2004. During FY 2006, personnel from both The Institute for Genomic Research and ARS Insect Biological Control Laboratory visited our laboratory to see our rearing operation and to assist in dissections to obtain material for establishment of BAC libraries and polydnavirus sequencing. A manuscript on the first description of a proviral locus is in preparation.
Roger Fuester. Classical Biological Control of Emerald Ash Borer and Asian Longhorned Beetle. At the North American Forest Insect Work Conference, Asheville, NC, May 22-26, 2006
Roger Fuester. Led Forest Ecology class at University of Delaware on all day tour of New Jersey Pine Barrens: showed and provided commentary on edaphic and geologic features, different forest types (e.g., upland, lowland, cedar bog, dwarf forest, etc.), fire ecology, and insect pest outbreaks (gypsy moth and southern pine beetle) (June 2006).