1a. Objectives (from AD-416):
Objective 1: Develop new knowledge of the behavior, genetics, systematics, physiology, ecology, and biochemistry of the insect pests of apple, pear, and cherry, and their natural enemies, that will aid in the discovery, development, and application of management methods and technologies. Sub-objective 1A: Evaluate habitat modifications and predation as factors in pest insect suppression. Sub objective 1B: Determine morphological characters that can be used to discriminate apple and snowberry maggot flies. Objective 2: Identify genes, receptor proteins, and respective ligands that are critical to codling moth development and reproduction. Objective 3: Discover and develop chemical attractants for codling moth, fruit flies, pear psylla, and other insect pests of temperate tree fruits and their natural enemies. Sub-objective 3A: Determine attractiveness of semiochemicals for codling moth and other pests. Sub-objective 3B: Optimize the pear psylla sex pheromone and other pest lures. Objective 4: Determine the impact of pest management and cultural practices on beneficial insects to improve biological control of the codling moth, pear psylla, and other insect pests of temperate tree fruits. Objective 5: Develop systems approaches involving combinations of various methods and technologies, both for management of codling moth in suburban and agricultural settings, and to reduce the probability of insects infesting fruit that is packed and shipped domestically and internationally. Sub-objective 5A: Implement a monitoring-intensive management program for codling moth that reduces the use of insecticides. Sub-objective 5B: Develop computer modeling of codling moth quarantine risk. Sub-objective 5C: Evaluate brown sugar and hot water methods for the detection of cherry fruit fly larvae in cherries. Objective 6: Develop applications of insect pathogens, attract and kill technology, and disruption techniques to control codling moth and other pests of temperate tree fruits. Sub-objective 6A: Develop attract and kill station designs for managing codling moth and other pests. Sub-Objective 6B: Develop applications of entomopathogens for control of codling moth.
1b. Approach (from AD-416):
Analysis of DNA sequences in the gut contents of arthropod predators in orchards will assess their consumption of orchard pests in order to rank their importance to biological control. Extra-orchard hedgerows of native plants will be studied for potential to improve overwintering of parasites and predators of orchard insect pests. A combination of morphological shapes will be used to determine best diagnostic traits for identifying problematic species of fruit flies. Protein receptors and their encoding genes will be identified, and their corresponding ligands will be determined in support of work to develop species specific behavioral and physiological modifying analogs for use in pest management. Chemical attractants from host plants of pest insects will be identified and developed as lures for traps and baits. Pear psylla pheromone will be developed as a lure for field use through comparison of pheromone formulations, doses, and trap designs. Sublethal and delayed effects of pesticides on spiders will be determined, including impact on spider reproduction. Information from global positioning systems will be used to identify, evaluate and manage pest hot spots in orchards. Traps baited with kairomonal attractants will be tested as a strategy to reduce codling moth populations in orchards, and manage codling moth populations through the removal of female moths captured in traps. The risks of introduction and establishment of codling moth in other countries will be modeled mathematically to determine important gaps in our knowledge of the pest biology. Sugar solutions will be tested as a means to float cherry fruit fly larvae from fruit as a potential detection method. Attract and kill stations will be designed and evaluated as a means to manage codling moth.
3. Progress Report:
Progress was made on all six objectives. For objective 1 we determined impact of host fruit on codling moth fecundity, cherry fruit fly use of wild and domestic fruits, and impact of soil moisture on emergence of cherry fruit fly. Kairomones from apple, hawthorn, and snowberry fruits attracted apple maggot flies, and flies preferred kairomones from their respective apple or hawthorn hosts of origin. For objective 2, we identified codling moth gene transcripts that we expect code for odorant receptor, chemo receptor, neuron membrane, and odorant degrading proteins, and cloned transcripts of 11 of these. We identified three navel orangeworm gene transcripts that we expect code odorant receptors. We cloned 8 spotted wing drosophila gene transcripts that are analogous to genes encoding critical function neuropeptides and receptors in other Drosophila. For Objective 3 we discovered new attractants or attractant blends for codling moth, oriental fruit moth, and spotted wing drosophila, and evaluated trap design parameters for oriental fruit moth , spotted wing drosophila, cherry fruit fly, and pear psylla. Known wasp attractants were tested as lures in traps to capture Polistes paper wasps, but without success. For objective 4 we determined the incidence of predator (ground beetle, spider, earwig, Opiliones, bats) consumption of codling moth, by using a PCR technique to identify prey DNA in predator guts and feces. We determined toxicity of several pesticides to spiders as biological control agents, with some supposedly soft pesticides showing high toxicity. A new species of anthocorid predator of pear psylla was discovered. A foam formulation was developed for application of lacewing eggs to orchard trees. For objective 5 we developed data bases on codling moth, apple maggot, and western cherry fruit fly, to be used to develop ecological niche models. These models would predict pest potential to establish in countries importing fruit from the PNW. A preliminary model for the apple maggot was developed. The impacts of temperature and day length on emergence of apple maggot and cherry fruit flies were determined. Pesticide laden GF-120 and sugar baits were tested for control of cherry fruit fly, with good efficacy. A comparison was made of salt and sugar solutions in a flotation method for finding maggots in cherries, with a slightly better efficacy using salt. For objective 6 we determined an optimum shape and size of a visual and physical target in an attract-and-kill design. Preliminary field tests in apple orchards indicated that 50 attract and kill stations baited with codlemone and pear ester may be effective enough to warrant large scale field trials. Field experiments demonstrated the efficacy of microenscapsulated sex pheromone and pear ester as attractants for the codling moth.
1. Development of ecological niche models for predicting establishment and Sspread of tree fruit pests. The risk of temperate fruit pests entering and establishing in export market countries has resulted in the imposition of quarantine and trade barriers against U.S produced apples and sweet cherries. Scientists at the USDA-ARS laboratory in Wapato, WA, developed informational databases on codling moth, apple maggot, and western cherry fruit fly based on publications and pest reports, which were then used to develop ecological niche models. These models predict the potential of these pests to establish and spread in countries importing apples and sweet cherries from the Pacific Northwest. This information can be used in bilateral trade negotiations with countries currently imposing quarantine and trade barriers against the import of these fruits. Removal of trade barriers will improve the ability of the tree fruit industry to expand its exports to these countries.
2. A synthetic chemical lure for spotted wing drosophila. The spotted wing drosophila is a new invasive pest of soft fruits, originating in Asia but recently spreading through North America and Europe. ARS researchers at the Yakima Agricultural Research Laboratory, Wapato, WA, working with scientists with the Oregon State Department of Agriculture, Salem, OR, and ARS Poplarville, MS, isolated and identified a set of chemicals from the odors of wine and vinegar that is attractive to spotted wing drosophila flies. When used as a lure in a trap in the field, this chemical blend was found to be similar in attractiveness to a mixture of wine and vinegar found previously to be a superior bait for the fly. This result provides the first chemical lure for the fly, which will enable development of a commercial lure, dry traps, and improvements in early detection of spotted wing drosophila in orchards and vineyards.
3. Effects of soil and air moisture on emergence of cherry fruit fly. The western cherry fruit fly damages sweet cherry fruit and is a major quarantine pest of cherries in the western U.S. Determining environmental requirements of the fly is needed to help predict whether it can establish in different regions where cherries are grown. ARS researchers at the Yakima Agricultural Research Laboratory in Wapato, WA, tested the effects of different soil moistures and air humidity on the ability of fly pupae to survive and emerge as adults. It was found that flies emerged at high levels under a wide range of dry to moist soil and air conditions. This result helps explain the broad distribution of the fly and can be used to assess the risk of it becoming a pest in regions where it is not currently found.
4. Predators help codling moth control. Many insecticides for codling moth control in apples and pears have been replaced by a newer product which may be safer for beneficial predatory insects and spiders which may help control pests. USDA-ARS scientists in Wapato, WA, used DNA amplification techniques to detect codling moth remains in the guts of predators collected from apple orchards in Washington and in the feces of bats in a California pear orchard. Analysis of the spider community, predatory beetle species and earwigs showed that 7 spider species utilized codling moth as prey, with >14% of the individuals of the spider community doing so. More than 10% of predatory beetles, earwigs and bats that were tested used codling moth as prey. These data coupled with quantitative estimates of between 1-2 predators beetle and earwig predators per square meter in the two studied apple orchards indicate that the predator complex can provide significantly mortality of codling moth larvae in orchards where predators are abundant.
5. Characterization of pheromone receptors in navel orangeworm and codling moth. Lepidopteran larvae cause major crop damage in orchards and control of these insect pests is mainly achieved through repeated applications of chemical insecticides. Pheromone-based control strategies have been incorporated in the orchard to reduce insecticide applications. To enhance the effectiveness of pheromone-based control and to develop more potent pheromone mimics, a better understanding of how insects detect and respond to these semiochemical cues is needed. ARS scientists in Wapato, Washington have developed a method to identify pheromone receptors (key mediators of pheromone perception) in codling moth, and in collaboration with researchers at the University of California, Davis applied this method to identify three pheromone receptors in navel orangeworm. The navel orangeworm receptors were characterized and one was shown to be specifically activated by the main sex pheromone, suggesting a role for this receptor in pheromone perception. Further characterizations determined that a pheromone mimic not only activated the navel orangeworm sex pheromone receptor, but does so more potently. Application of this research is now being used to facilitate the development of more effective pheromone-based control strategies that will lead to further reductions in chemical insecticide applications and reduce crop damage caused by insect pests.
6. New multi-species insect lure for pome fruits. Apples and pears are attacked by a number of tortricid moth species including codling moth, oriental fruit moth, and a suite of leafrollers. Currently growers use separate traps to monitor each species and this cost causes many growers to not adequately use traps to monitor all three species. ARS researchers at Wapato, WA have developed a lure combination that can be effective for all of these tortricid pest species. A lure consisting of sex pheromones, plant volatiles, and acetic acid is effective in detecting local pest populations. The relative lower cost of monitoring all of these pests with one trap may increase grower’s use of moth catch action thresholds to apply insecticides only when needed.
Landolt, P.J., Brumley, J.A., Guedot, C.N., Wanner, K.W., Morales, A. 2011. Male Fishia yosemitae (Grote)(Lepidoptera: Noctuidae) captured in traps baited with (Z)-7-dodecenyl acetate and (Z)-9-tetradecenyl acetate. Journal of Kansas Entomological Society. 84:184-189.