Brief Summary of Minutes of Annual Meeting

Goal A: Import and Establish Effective Natural Enemies Objective 1. Survey indigenous natural enemies. Surveys for natural enemies of arthropod and weed pests were conducted either in the native home of the pest or within the country of invasion. Surveys for natural enemies in foreign countries are reported under Objective 2. California pests for which surveys were conducted over the last year include: citrus leafminer; soft scales occurring on citrus in central and southern California; mealybugs in Californias central valley and costal wine grapes; olive fruit fly and glassy-wing sharpshooter. Surveys for assassin bugs in Southern California started - species of Zelus, among them the leafhopper assassin bug Z. renardii, which is native to California, feed on a wide range of prey organisms, including lygus bugs, caterpillar larvae, and boll weevils. In Amer. Samoa, surveys focused on enemies of Seychelles scale and erythrina gall wasp. Objective 2. Conduct foreign exploration and ecological studies in native range of pest. Several institutions in the western US conducted foreign exploration and importation of natural enemies for both new and established arthropod and weed pests this past year. The following list includes pests for which exploratory research was conducted: Salsola sp. in Turkey, Tunisia, Greece, Iran and China; erythrina gall wasp in South Africa, Mozambique and Madagascar; yellow starthistle in Turkey; olive fly in Namibia; light brown apple moth in Australia; hackberry aphid in China; vine mealybug in France; African rue in Turkey; obscure mealybug in New Zealand; chrysopids in Brazil; Russian knapweed in Iran; and Russian olive in Uzbekistan, Turkey, Iran and China Objective 3. Determine systematics and biogeography of pests and natural enemies. The phylogenetic relationships of the Nearctic and Neotropical genus Apiomerus were studied using molecular information. Several genes have been evaluated. Methods have been developed to identify cryptic "species" of P. chalcomera by molecular genetics. A previously unknown cryptic species of Cales noaki has been identified using molecular markers which is highly localized in a citrus grove on the UCR campus. Research was completed on a study of the molecular phylogenetics of Aphelinus parasitic on Russian wheat aphid. The phylogeny of Qudrastichus spp. was reconstructed using CO1 and elf1 genes. Molecular analysis has begun on collections of vine mealybug from many of the worlds Mediterranean regions to separate populations, in order to determine where vine mealybug in California originated. Psyllaephagus species, collected on spotted gum psyllid, are being separated. Objective 4. Determine environmental safety of exotic candidates prior to release. Every year, more effort goes into testing natural enemies for host specificity prior to applying for environmental release. Examples follow. Host plant specificity and target plant impact studies were conducted on G. canella, using an eriophyid mite, an enemy of Russian thistle. Host plant specificity studies were conducted on the flea beetle, P. chalcomera, against yellow starthistle. A field release permit for two parasites of the olive fly: P. lounsburyi and P. ponerophaga, was obtained. Results of host-specificity tests conducted with the seed feeding weevil C. turbatus show that it is the most specific agent investigated. Because it only reduces seed output of L. draba, it will not contribute to the control of existing stands, but rather to the spread. Non-target studies were conducted with imported fruit fly parasitoids to investigate effectiveness against olive fly and non-target fruit fly species, particularly the beneficial C. succinea, and P. regalis, which will be released for control of Cape ivy. Non-target studies were conducted in quarantine with P. maculipennis, an encyrtid parasitoid of the obscure mealybug. Objective 5. Release, establish and redistribute natural enemies. The Tamarix leaf beetle, D. elongata, has become established in California and was provided to California Dept. of Food and Agriculture for distribution against saltcedar. Trichogramma spp. in Hawaii, (attacking eggs of H. zea in seed corn), were collected, identified and mass reared. Promising results were obtained, with T. papillionis providing the highest levels of field parasitism following augmentative releases. The CDFA insectary in California, was supported by USDA-APHIS to produce A. kamali and G. indica for release against pink hibiscus mealybug in Louisiana. Over 68,000 A. kamali and 80,000 G. indica were sent to Louisiana for release. Strains of C. peregrinus (South Africa) and A. pseudococci were released in vineyards in California. Both parasitoid species were recovered. Extensive redistribution of the foliage feeding/stem boring weevil M. janthinus was continued and this weevil has impacted populations of Dalmatian toadflax throughout eastern Washington. Demand for this natural enemy from weed-plagued landowners remained high, with 111,850 adults being released. Objective 6. Evaluate natural enemy efficacy and study ecological/physiological basis for interactions. Field studies were conducted on the introduced rust, P. jaceae var. solstitialis, used against C. solstitialis, and lab. studies determined the response of teleospores to environmental conditions. Foliar phosphorus levels had no impact on feeding on Canada thistle leaves by adult Cassida rubiginosa under no-choice conditions; however, beetles preferentially fed on Canada thistle with higher phosphorus levels when given a choice between leaves from low- and high-phosphorus treatments . Experiments investigated the combined impacts of 3 different herbicides and the biocontrol agent of Canada thistle. Impact on thistle root biomass was greatest in treatments combining biological control and the herbicide clopyralid, though herbicide and biocontrol impacts were additive and not synergistic. The egg parasitoid, A. vaquitarum, is being imported into California from Florida. Goal B: Conserve Natural Enemies to Increase Biological Control of Target Pests. Objective 7. Characterize and identify pest and natural enemy communities and their interactions. Chrysopids and hemerobiids associated with pests in orchards, field and row crops, were identified. Studies on natural enemies attacking the citrus leafminer in California began this year. Molecular work with Rhinusa hispida and Mecinus heydeni has confirmed the complex relationship of most toadflax insects with their host plants in Europe and the need to test these species separately. Extensive no-choice and multiple-choice tests were carried out with R. hispida from L. vulgaris, confirmed its narrow host range and potential as a biological control agent. The cost-reliability of 5 sampling methods for estimating the density of arthropod predators in cotton was studied in Arizona and Texas. A beat-bucket sampler was the most efficient and economic method and fixed-precision sampling plans were developed for several key predator species. Laboratory studies were completed to determine and compare maximal rates of reproduction of 4 species of native lady beetles versus the introduced lady beetle C. septempunctata when provided with excess pea aphids, the major prey of these predators in Utah alfalfa fields. Objective 8. Identify and assess factors potentially disruptive to biological control. Field experiments assessed the extent of cannibalism or intraguild predation which might limit the ability of Geocoris pallens to exert biological control of L. hesperus and T. urticae. Results suggest that cannibalism may be a limiting factor. The selectivity of several new insecticides for whitefly control was studied. Results suggest that spiromesifen has a dose-dependent effect against generalist predators and that low rates of this might may be useful in IPM for Bemisia tabaci. Field studies focused on the selectivity of new insecticides for Lygus control in cotton. Flonicamid, appears to have efficacy against Lygus but shows no measurable effect on natural enemies. Its been established that insecticide treatments for glassy winged sharpshooter in CA, disrupt biocontrol in citrus. Invasive ants were surveyed on Guam, Saipan, Tinian, and Rota. A. gracilipes protection of C. pandava may disrupt natural enemy predation and parasitism on C. pandava. Objective 9. Implement and evaluate habitat modification, horticultural practices, and pest suppression tactics to conserve natural enemy activity. Intercropping during the summer months in broccoli, reduced aphid pressure, where insect pest pressure is highest. Mustard is more effective than buckwheat as an intercrop, due to its trap cropping effect on aphids. Mono and polyculture broccoli plots exhibited lower aphid densities and higher parasitization rates when fertilized with compost. Studies examined the movement of lygus bugs and associated natural enemies between alfalfa, cotton, lesquerella and guayule. Results indicated that Lygus and several species of predators readily moved from senescing lesquerella into cotton but not guayule. Studies are underway to examine Lygus and natural enemy movement between cotton and alfalfa. Augmentative releases of Metaphycus species are being tested for suppression of citricola scale in CA. Goal C: Augment Natural Enemies to Increase Biological Control Efficacy. Objective 10. Assess biological characteristics of natural enemies. To elucidate predation strategies of species of the assassin bug, Zelus, lab cultures were established of Zelus renardii and Zelus tetracanthus. Adults of Zelus luridus engage in sticky trap predation enabled by glands on the legs that release a sticky secretion. A large scale mark-release-capture experiment was conducted to quantify movement of a group of generalist predators (Geocoris spp., Nabis spp., and H. convergens) on a landscape scale (up to 5 kilometers). Genetically selection for specific traits in the predatory mite, P. persimilis, for improved biological control of twospotted spider mites on greenhouse crops, is underway. Lines of P. persimilis have been selected for increased prey consumption, conversion efficiency, dispersal, and response to spider mite-elicited plant volatiles. Objective 11. Develop procedures for rearing, storing, quality control and release of natural enemies, and conduct experimental releases to assess feasibility. Studies have been reported under many of the other objectives. A few examples follow: Five of the known ecotypes of D. elongata (against saltcedar) are being maintained in the New Mexico State University quarantine lab. Populations from the following locations are in culture: Crete, Greece; Possidi, Greece; China; Fukang, China, and Karshi, Uzebekistan. Techniques to improve rearing and development of laboratory populations continues to be a priority. In pistachios, augmentative releases of Bracon nr. sp. cushmani (Hym.: Braconidae) for the control of obliquebanded leafroller were tested. Augmentative releases did not provide improved control. In vineyards, A. pseudococci was released in conjunction with placement of plastic membrane dispensers containing the vine mealybug sex pheromone. Initial results suggest parasitism is higher when the pheromone is present. Objective 12. Implement augmentation programs and evaluate efficacy of natural enemies. Trichogramma species present in Hawaii, and attacking eggs of H. zea in seed corn production, were collected, identified and mass reared. Two species, T. achaeae and T. papillionis, were mass reared and experimental releases were conducted in seed corn plots to determine if these species had potential to suppress H. zea. Researchers at Cornell (collaborating with Mexico and Brazil) evaluated the potential of chrysopids for mass-rearing and release in the U.S. and Latin America. Large numbers of Metaphycus can be reared for release and will reduce scale density when scale densities are clearly economic (100 citricola scale per 10 leaf terminal). Innundative strategies continue to be successful against patches of leafy spurge. Goal D: Evaluate Environmental and Economic Impacts and Raise Public Awareness of Biological Control. Objective 13. Evaluate the environmental and economic impacts of biological control agents. Field experiments in Italy evaluated the specificity and impact of the eriophyid mite, Aceria salsolae, on Salsola tragus. Validation of risk assessment procedures for non-target impacts of classical biological control on indigenous species is being examined. The impacts of five adventive and two purposefully introduced parasitoids on an endemic (Hawaii) moth was examined. The adventive species had the largest impacts. Purposefully introduced species were present in only a few of the study sites, those at highest elevations. Long-term censusing of lady beetle species exploiting alfalfa fields of Utah was continued to evaluate effects of the introduction and establishment of the exotic lady beetle, C. septempunctata, on native coccinellids. Objective 14. Develop and implement outreach activities for biological control programs. Biocontrol research of western weeds was presented at an annual Wyoming meeting of state weed managers, federal agency employees and University of Wyoming personnel. Presentations on vine mealybug were made to growers/regulators on how to communicate risk of invasive species to the public. Three seminars on biology/damage of Diaprepes root weevil were given to grower and industry groups. Three workshops on Diaprepes were held to educate the nursery industry on the pest, its control, and regulations. A 3-hour short course on biocontrol was given to CA county biologists as preparation for a licensing exam. An educational workshop on the biocontrol of puncturevine was held in CA. During the workshop, two beneficial weevils, the seed weevil, M. lareynii and the stem weevil, M. lypriformis were distributed to attendees for release on their property.