The annual reports are broken up into sections. Click on the tab heading to view the report section submitted by the respective section investigation leader.
California: Mike Devencenzi, Joseph Grant (UCCE), Jed Walton, Dr. Marshall Johnson (UC Riverside, outside scientist), Carolyn Pickel and Walt Bentley (UCIPM), Drs. Pete Goodell, Lucia Verela and Tunyalee Martin (UCIPM)
Oregon: Rich Garvin, Bruce Decker, Jeff Olsen (OSU Extension)
Washington: Dan Flick, Nick Stephens, Karen Lewis (WSU Extension), Dr. Doug Walsh (WSU, outside scientist)
Canada: Dr. Gary Judd (Agriculture and Agri-Food Canada, outside scientist)
Our project officially ended on 31 August. However, the official end is not the end of the project and we have leveraged the SCRI funding well beyond the initial 1:1 match, with at least an additional $1.8 M in new grant funds to expand on the original objectives and also to bolster the outreach efforts.
For this progress report, we will provide a short overview of the accomplishments for each objective, as well as showing some of the exciting new research and extension directions that have been taken by some of our project directors. We also provide a comprehensive list of publications, presentations, leveraged grants, and the training opportunities that this SCRI grant has helped fund or that is an outcome of the leveraged funding. We think that our productivity has been extraordinary, with 92 presentations, 31 additional symposia presentations (with 9 more coming in 2014), 21 popular articles, 26 peer-reviewed articles in print or in press, and a special issue of the journal Biological Control that will have 14 additional peer-reviewed articles, a two-day short course presented at 3 locations over video conference, more than twelve 2-4 hour training courses on natural enemies and a state of the art web site that pulls all this together (enhancedbiocontrol.org).
We hope you enjoy the report and find our results and new directions to be a clear indication of our passion for both basic and applied research, the excellence of our team, and the importance of taking a broad and fresh approach to integrating biological control into normal orchard management programs.
For more information on this project and our accomplishments, please visit our web site (enhancedbiocontrol.org) and feel free to contact our project directors.
Although the project directors are ultimately responsible for the work done in this project, there is also a key group of post-doctoral research scientists and technical support personnel that have been essential to our project through their dedication and hard work. We gratefully acknowledge their efforts to make the project a success:
This objective has successfully characterized the potential disruptive effects of seven different pesticides used for management of codling moth and diseases on a set of natural enemies that contribute to the management of secondary pests in western apple, pear and walnut orchards. Detailed laboratory tests designed to integrate both acute and sublethal effects of pesticides on natural enemies led to the development of a simple visual chart summarizing the relative compatibility of each pesticide with natural enemies (below; enhancedbiocontrol.org/pe.html). Follow-up studies in apple, pear and walnut orchards were used to confirm the strongest disruptive effects seen in the laboratory tests on the ratio of natural enemies to secondary pests, which is a useful index of biological control activity in the field. This information has already been incorporated into the decision making of a number of leading pest managers throughout the region, and is being used in educational programs associated with the project. We anticipate this information will result in enhanced conservation of biological control agents in western orchards and reduce the need for pesticide applications against secondary pests in these crops.
The accomplishments from the project include significant advances in both science and industry application. From a science perspective, the project has generated the first larger scale application of life table statistics to the laboratory assessment of pesticide risk to natural enemies and provides a framework of standardized protocols for rigorously testing pesticide selectivity. Benefits to the tree crop industries have been twofold: First, growers and pest managers have become increasingly aware of the importance of the biological control services that natural enemies can provide if not disrupted by indiscriminate use of pesticides. Secondly, this awareness has encouraged them to question whether changes in pesticide registration in these crops could be responsible for the novel secondary pest complexes that have arisen in recent years. Consequently, this has led to a series of new industry-sponsored research projects in all three states that are geared toward enhancing the role of biological control in the management of secondary pests such as aphids, pear psylla, and spider mites.
Phenology models have been developed for two lacewings (Chysopa nigricornis, Chrysoperla plorabunda) and a syrphid fly (Eupeodes fumipennis), and we are working on at least two more. There is more data from apple orchards than all other crops, so we developed the models using a subset of the apple data, and then validated the model using the remainder of the apple data. The apple models were then tested in cherry, pear, and walnut orchards to check for significant departure. Our average error with the models for the lacewing Chrysopa nigricornis was similar in the two different areas of Washington tested, and California, but were roughly 40% higher in Oregon (HR, figure on right). We are not sure why the Oregon data had higher errors, but it is not related to differences in crops, since both cherry and pear orchards in Washington fit the apple data similarly to the apple validation data. We are currently evaluating the different spray programs to see if that explains the differential errors in Oregon.
The phenology models for natural enemies are merely extensions of the theory used to to develop phenology models for pest insects. However, they are an advance in the sense that we found that the phenology in our systems could be predicted solely by temperature accumulations, and did not require information on the host or prey populations levels. We also found that a single model for each natural enemy had similar accuracy in all crops, except in situations where pesticide use was excessive
The models provide the industries precise information on when different natural enemies occur. In particular, we found that the lacewing, Chrysoperla plorabunda and the syrphid flies (Eupeodes fumipennis and Eupeodes volucris) occur much earlier in the season than previously expected. Our data suggest that we need to re-consider the pesticides used, timing, and the particularly the delayed dormant sprays in all three crops. Ultimately, we expect that we can use our data from this and leveraged projects to generate at least five phenology models that are important to a range of our key pests in western orchards. These models will be be delivered through the WSU-Decision Aid System and provided to the researchers in Oregon and California for implementation in those states.
The work performed in this objective makes our project the best source of information for the effect of a wide range of floral volatiles and herbivore-induced plant volatiles on natural enemies on different crops in widely separated locations. In addition, the factorial design of our experiments allowed us to evaluate how different potential attractants work together and give us a much more complete picture of how to combine several different volatile components together to make lures that are not only more attractive, but also more selective for different natural enemy groups. We found that 2-phenyl-ethanol (PE) was highly attractive to several species of syrphid species, and some selectivity between species was possible by adding either methyl salicylate (MS) or geraniol (GER). Lacewings (Chrysoperla plorabunda) responded strongly to a variety of volatiles and optimal attraction required lures combining three different volatiles. However, because of interactions between the different volatiles, there were multiple combinations that provided the same response. Acetaphenone (AP) was important for C. plorabunda, but only when mixed with other components. A broad range of Hymenopteran taxa responded to virtually any lure combination that contained phenylacetaldehyde (PAA) as one component.
Our studies showed an astonishing variety of natural enemies could be found at various times and abundances in agro-ecosystems. For example, in apple we regularly monitored >120 different natural enemies. The traps are very sensitive indicators of species presence and abundance that may change our basic understanding of population interactions. Our studies also showed that particular lure combinations work regardless of the crop system, which means that our research should translate to other crop systems which often share similar generalist natural enemies. The discovery that PAA was attractive to all hymenopterans (including honeybees) makes that compound a particularly powerful tool for studying ecosystem function because of the importance of the parasitic Hymenoptera in regulation of a wide range of insect pests.
From the standpoint of benefit to the industries, we now have sensitive traps that work for monitoring a range of natural enemy groups important in apple, cherry, pear, and walnut orchards in the western region. These traps can provide the information on natural enemy abundance throughout the season (useful in model development (objective 2)), and for understanding the effects of different control tactics on natural enemy population dynamics. Our research also showed that syrphid flies and lacewings could be used as indicator species to help simplify trap use for pest management purposes.
We also worked with the Objective 6 group to put out grower/consultant trials in Washington and Oregon of the squalene lure, which attracts the lacewing Chrysopa nigricornis. These trials were to familiarize participants with the lures and compare different management tactics on the lacewing.
Previous studies suggested that predation rates on mature codling moth larvae were 30 – 40% when pesticide use was moderate. Here we designed a study to identify which predator groups contribute most to codling moth mortality. Molecular gut content analysis was chosen because predators usually eat their prey and leave little visual trace of their activities. Our detection of codling moth DNA in predators provided a semi-quantitative measure of what proportion of each predator group had recently fed on codling moth. The results are conservative because digestion of the codling moth (and consequently their DNA) within the predator limits detectability to just a few days. Even so, we found earwigs, spiders, and carabid ground beetles were important due to their abundance and high feeding rates on codling moth (right).
Molecular gut content analysis of prey DNA is not new to science, however it is expensive. One technique developed during this grant has streamlined and reduced the cost of sample processing that will allow future studies to analyze significantly more specimens. As agricultural entomologists, we generally know which groups of predators were likely to be important but the activity by earwigs was both a surprise and a minor concern for some members of the industry. In some apple varieties, earwigs can sporadically cause minor fruit damage. Earwigs are well known to be important predators of woolly apple aphid, an increasingly important pest in newer apple plantings. Future studies to evaluate how earwigs may affect fruit damage compared to their contribution to overall biological control will be important knowledge for the design of sustainable IPM programs in tree fruits.
The economic analysis showed that both apple and pear growers were willing to pay extra for insecticides that would preserve natural enemies. Surveys showed that apple growers were willing to pay $26.60/acre to decrease toxicity to natural enemies, $61.83/acre to be less toxic to wildlife and $43.10 to decrease toxicity to aquatic organisms. Pear growers showed different trends with a willingness to pay $33.37/acre to decrease toxicity for natural enemies, $25.28/acre for decreased toxicity to wildlife and $19.68/acre for reduced toxicity to aquatic organisms.
A second analysis focused on how the use of pesticides disruptive to natural enemies affected costs of controlling secondary pests. Examination of spray records for seven apple orchard operations in Washington found that for every $1 spent on insecticides that were toxic to natural enemies, an additional $0.52 was spent on secondary pests. Similarly, analysis of the spray records for 10 pear orchards in the Hood River of Oregon showed that for every $1 spent on disruptive materials that $0.47 was required to control secondary pests.
Both of these studies show that economic incentives exist to conserve natural enemies and that growers and IPM practitioners recognize and are willing to pay to enhance biological control.
A large amount of this project’s resources were dedicated to outreach activities, highlighting the importance the project participants put on this aspect of the project. Without effective outreach activities the results generated by projects such as this one generate new scientific information, but do little to change perceptions and practices of stakeholders. The goal of the outreach objective was not just to develop knowledge and technology for the apple, pear and walnut industries, but to integrate this information with older information and deliver it in a way that would impact their decision-making and management practices.
In the final year of our project we focused our activities in two major areas, hands-on mini-workshops and further development of web resources. We knew from research that students retain new information better when they are actively involved in the learning process. Therefore, the hands-on mini-workshops involved meeting with small groups from key industry organizations, especially those shown to be early adopters of new knowledge and technology, were conducted in an engaging and interactive way. We held 10 mini-workshops over the winter of 2012/13 that included a total of 175 participants. We anticipate more rapid adoption of basic and new biocontrol information and practices through these hands-on educational activities. For the workshops, we developed hand-out materials including natural enemy fact sheets as well as a 19 x 13-inch natural enemy wall poster, which has been very popular with workshop participants and at grower meetings. These hand-out materials can also be downloaded from our project website.
Preserving our project results and providing useful resources for our stakeholders has been a top priority of this project from the start. We’ve tried to stay ahead of the changes in digital technology by frequently updating our web platform and it is currently available on nearly any platform/device combination. The website (enhancedbiocontrol.org) is a repository of all of the research results from the project’s different objectives in many forms. For Washington growers, the information generated by the project is also being incorporated into the WSU-Decision Aid System (das.wsu.edu) which is used to make IPM decisions on >80% of Washington tree fruit acreage.
In addition to comprehensive reports, the project website contains a listing of all related publications with links for reading, printable identification guides, workshop handouts, viewable presentations, natural enemy image galleries, videos of techniques and collaborator insights, and an interactive pesticide effects table developed from the results obtained in Objective 1, as well as a compiled database of pesticide effects on natural enemies that will be placed both on our project web site and the WSU-DAS website. The website will remain accessible well beyond the end of this project and thanks to new leveraged funding, we will continue to update and add features making it an enduring legacy.
We organized symposium entitled “Progress towards integration of conservation biological control in Western apple, pear, and walnut orchards” on our project for the Pacific Branch of the Entomological Society of America that will be presented at the Tuscon meetings in 7-10 April with the following titles and speakers:
We have contacted the journal Biological Control and arranged for the publication of a special issue with 14 different articles (below) all by our team members. These articles will go through the normal peer review process and be published together in a single issue devoted to our project. This method of publication brings our work together in a single location available in the best libraries in the world as well as available on the internet.
This project will provide for more hands-on workshops as well as an online course that will focus on the basics of biocontrol, key natural enemies in orchards, newly developed tools to monitor and predict natural enemy presence, and pesticide effects on natural enemies; all knowledge gained from this SCRI project. We will also create an innovative and user-friendly pest and natural enemy identification guide available online and as a mobile app to complement the on-line course. In addition, the funding will allow us to extend work performed over the past 2 years with IPM practitioners to evaluate new natural enemy monitoring tools in their orchards and provide feedback. The new project’s outcomes have the potential to benefit the entire tree fruit industry through increased awareness and utilization of biocontrol resulting in reduced pesticide applications/costs and increased worker, food, and environmental safety.
This project used the attractant lures developed in objective 2 of the SCRI grant. We focused on the differences in the natural enemy complexes in paired organic and conventional orchards. The data from this project were taken in the same manner as used in our studies done in the SCRI grant in objective 2, which expands the data available to make natural enemy models. The work done under this project also showed that we could use conventional pesticides at low rates (10% field rate) with timing and treatment intervals similar to organic treatments and still achieve commercially acceptable damage levels similar to either organic or conventional programs. The low rate treatments had similar natural enemy abundance and diversity as the organic treatments at a very low cost and with an 80% reduction in pesticides applied.
These two grants are aimed at improving the WSU-Decision Aid System (DAS), by incorporating models developed using data from the the SCRI project and by collecting more data to generate new models of not only natural enemies, but also pests. These grants also provided funds to enhance our outreach efforts to users throughout the state of Washington, develop orchard management systems to help minimize pesticide use in orchard systems, and to develop push notifications so that growers are alerted immediately when critical IPM events occur or are predicted to occur.
This grant is a spinoff from Objective 1 of the SCRI grant. Both the large scale field trials and the lab trials were difficult, very expensive, and prone to problems associated with year-to-year variation in pest and natural enemy population levels. This leveraged project uses field-aged residues to monitor how pesticides degrade over time and combines those data with state-of-the-art demographic models that mimic the phenology found in the field. These models then allow us to evaluate the effects of different treatment regimes for pests to evaluate the best ways to reduce pest populations while preserving natural enemy populations.
This project is focused on evaluating if the use of mating disruption for CM in pears allows improved biological control of pear psylla during the summer. It will use a combination of the technologies developed in objectives 1-3 from our SCRI project to help tease apart which natural enemies are more common and the best ways to conserve the natural enemies important in pear psylla population suppression.
|Investigator Links||Useful Links|
|Vince Jones||Jessica Goldberger||WSU DAS||UCIPM|
|Elizabeth Beers||Dave Horton||WSU-TFREC||BC Information Ctr.|
|Jay Brunner||Nick Mills||USDA-ARS Wapato||WSU PMTP|
|Steve Castagnoli||Peter Shearer||OSU-MCAREC||Orchard Pest Management|
|Karina Gallardo||Tom Unruh||ESPM||WA Crop Protection Guide|