1 A Compilation of Results of Sirex noctilio Projects by CPHST Scientists and their University Cooperators 2006-2012 David W. Williams and Victor C. Mastro USDA, APHIS, PPQ, CPHST Otis Laboratory Buzzards Bay, Massachusetts 02542 May 2015 2 Contents Chronology of the Sirex Program – 2004-2013………………………………….. 3 Executive summaries of Sirex noctilio projects………………………………….. 5 List of peer-reviewed publications produced by the Sirex noctilio program…. 14 I. CHEMICAL ECOLOGY……………………………………………………… 16 Katalin Bӧrӧczky; Pennsylvania State University………………………….. 16 Miriam Cooperband; USDA, APHIS, CPHST Otis Laboratory……………. 19 II. SURVEY AND TRAPPING…………………………..………………………. 42 Damon Crook; USDA, APHIS, CPHST Otis Laboratory………………….. 42 Kelley Zylstra; USDA, APHIS, CPHST Syracuse Laboratory...................... 64 Joseph Francese; USDA, APHIS, CPHST Otis Laboratory……………….. 97 III. BIOLOGICAL AND NATURAL CONTROL……………………………… 106 David Williams; USDA, APHIS, CPHST Otis Laboratory………………… 106 Ann Hajek; Cornell University……………………………………………… 159 Kelley Zylstra……………………………………………………………….. 194 IV. COMMUNITY ECOLOGY…………………………………………..……… 199 Matthew Ayres; Dartmouth College………………………………………… 199 Kamal Gandhi; University of Georgia……………………………………… 202 V. MODELING…………………………………………………………………… 209 Scott Myers; USDA, APHIS, CPHST Otis Laboratory…………………….. 209 Kamal Gandhi ………………………………………………………………. 210 VI. MOLECULAR GENETICS…………………………………………………. 214 Evan Braswell; USDA, APHIS, CPHST Mission Laboratory……………... 214 Ann Hajek…………………………………………………………………... 218 3 Chronology of the Sirex Program – 2004-2013 Fall 2004 – Sirex noctilio trapped in Fulton, New York, during bark beetle survey. Spring 2005 – S. noctilio identified by E. Richard Hoebeke of Cornell University. July 2005 – Dave Williams asked to initiate Sirex biological control program. September 2005 – Williams traveled to Australia for two weeks to review Sirex program. Fall 2005 – Beddingia Lab established; Kelley Zylstra started work. Fall 2005 – Lynn Goldner (NPL) and Leon Bunce appointed to coordinate Sirex program. Fall 2005 – Environmental Assessment and Biological Assessment written. January 2006 – Robin Bedding visited and gave nematode short course. January 2006 – first session on Sirex at Interagency Research Forum on Invasive Species. January 2006 – Syracuse Lab established with Robin Tait as director. Summer 2006 – trapping work started around Syracuse. August 2006 – first imports of the Kamona strain of Beddingia siricidicola from Ecogrow. September 2006 – Sirex training session at SUNY Oswego. November 2006 – first controlled release of Kamona strain in central New York. January 2007 – first mass rearing of Kamona in Beddingia Lab. January 2007 – Zylstra became new director of the Syracuse Lab. May 2007 – Sirex Symposium in South Africa, Williams represented the Otis Lab. Summer 2007 – discovery of “native” strain of Beddingia siricidicola in New York. Summer 2007-2012 – continued trapping work. Fall 2007-2012 – continued controlled nematode releases. April 2009 – Robyn Rose replaced Goldner as NPL for Sirex. April 2009 – meeting with APHIS and Forest Service in Riverdale to discuss nematode releases. Spring 2010 – molecular work carried out by Evan Braswell. 4 May 2011 – review of Sirex research in Riverdale; Sirex officially turned over to Forest Service. July 2013 – Syracuse Lab closed. 5 Executive summaries of Sirex noctilio projects Sirex noctilio invaded Tasmania in 1952 and the Australian mainland in 1961. In response, the Commonwealth Scientific and Industrial Research Organization (CSIRO) rapidly developed a multipronged management plan for combating the pest. To characterize their program, CSIRO used the metaphor of a three legged stool. The legs were monitoring and survey, silvicultural practices, and biological control. CSIRO undertook directed research in these areas, recognizing the need to integrate the approaches. Following their metaphor, the stool needed all three legs to stand. Research was carried out worldwide through cooperation with other Commonwealth organizations. For example, the biological control leg was supported by global exploration for natural enemies over a range of taxa by the Commonwealth Institute of Biological Control in the United Kingdom. Thus, when S. noctilio invaded North America in 2004, CPHST already had a powerful model to adapt for use in a pest management program for the United States. The CPHST methods development program was ultimately similar to that of CSIRO, but more along the lines of traditional integrated pest management (IPM) as practiced in the U.S. since the 1970s. IPM is based on a strong foundation of biological and ecological knowledge, including our topical areas of chemical ecology, community ecology, and molecular biology. It is implemented by the development of survey tools, including traps and lures, the mass production and release of biological control agents, and the use of models to better understand and predict the risks posed by the target pest through its seasonal dynamics and host relationships. In the following, we present the salient features of the CPHST management program for S. noctilio in brief executive summaries and then expand on the details of research in its various components. I. CHEMICAL ECOLOGY Katalin Bӧrӧczky explored two aspects of the chemical ecology of Sirex: a contact sex pheromone and host volatiles of pine species that may attract wood wasps. Previous observations had suggested that many antennal receptors were contact chemoreceptors. Moreover, contact of these receptors with the body of a dead, pinned Sirex female elicited mating behavior in males. Washing of the pinned females with hexane halted the copulatory behavior. Bӧrӧczky undertook a series of experiments to verify the presence of such a pheromone and then identified it. She discovered that it consisted of three components and developed a synthetic version of the natural product. When she tested it on male Sirex, she found that it also elicited copulatory behavior. Stressed plants are known to emit volatiles and such substances often attract herbivores to a vulnerable host. Bӧrӧczky investigated the effects of girdling pine trees on their production of volatiles and their attractiveness to Sirex. She girdled two chemotypes of Scots pine as well as white pine with an herbicide and monitored the treated trees for the following eleven weeks. 6 Observations included weekly measurements of volatile emissions and counts of trapped Sirex females. In general herbicide treated trees captured more Sirex than the untreated controlled. The Scots pine with the high-carene chemotype attracted the most females to traps, followed by the low-carene chemotype and then the white pine. In all cases, trees that were girdled emitted more volatiles than controls, and the Scots pine chemotypes induced higher emissions than did the white pine. Bӧrӧczky observed qualitative differences in volatiles among the tree types, which may be a factor in their differences in attractiveness to Sirex. Moving to the southeastern United States, Bӧrӧczky is continuing her work on host volatiles, currently comparing loblolly pine, shortleaf pine, longleaf pine, and Virginia pine using the Gas Chromatograph – Electroantennogram Device (GC-EAD) technique. Miriam Cooperband discovered a sex pheromone that is produced by male Sirex and apparently causes males to aggregate. It is produced only by males older than two days – not by younger males or females – and probably serves to promote male lekking behavior, which is instrumental in the mating process. Cooperband made the discovery using a variety of techniques, including aerations, GC-Mass Spectrometer (MS), GC-EAD, and Y-tube olfactometer and wind tunnel bioassays. The three-part pheromone consisted of one major component and two minor ones. It was found to be attractive to both males and females in wind tunnel bioassays. Field tests of the pheromone were conducted in central New York State and South Africa to evaluate pheromone concentrations, trap design, and trap height above the ground. Unfortunately, results for the second year of this study suffered from an unforeseen problem: the presence of a contaminant that caused the major component of the pheromone to be non-attractive. Cooperband spent much time elucidating the cause of the problem and trying to obtain pure material. Results in the New York sites also were limited by very sparse Sirex populations. The pheromone is currently being evaluated in South Africa for use in mating disruption. II. SURVEY AND TRAPPING Chemical lures for Sirex may include pheromones and host kairomones. No long distance pheromones have yet been identified for the species but contact pheromones are a real possibility. Damon Crook has suggested this based on electron microscope investigations of antennal morphology. A study of characteristic mating behavior by males to dead pinned female wasps (see above) also provides evidence for a contact pheromone. Crook, along with cooperators from Pennsylvania State University, also investigated attractiveness of pine volatiles to Sirex. They compared healthy trees with those that had been girdled with herbicides. Overall, the girdled trees were much more attractive than were the healthy ones. Moreover, Scots pine was found to be more attractive than red pine, and red pine, more attractive than white pine in studies during 2006. In later studies, Scots pine was found to be much more attractive than white pine. Back in the lab, studies with a GC-EAD showed