Brief Summary of Minutes of Annual Meeting

The group met on January 12, 2018 on the Cornell campus in Ithaca, NY. We had 9 participants attending the meeting that was led and organized by Katja Poveda and Andre Kessler. All participants, except for one (Georg Jander) had attended the previous meeting and about half the participants have currently funding while the other half don’t have funding through this multi-state initiative, but are interested in being part of the group and writing proposals together.  This meeting was dedicated to obtain updates on the projects that people were involved, discuss the results and what they mean for sustainable management practices in the Northeast and to look for funding opportunities based on the preliminary data obtained.

The executive decisions that were made during this meeting, where:

• that the next organizational meeting was going to be organized in Penn State University, PA and will be taking place in October or November 2018.
• that the chair of the Executive Committee for the next year was going to be Jared Ali, the representative at large Gary Felton and that John Tooker would fulfill the role of secretary.

MEETING MINUTES (summary of main results and points discussed)

January 11, 2018

6 pm: arrival and dinner

January 12, 2018

9 am: Welcome remarks by Katja Poveda and Andre Kessler

9:15: Susan Whitehead

Susan presented her work on the evolutionary ecology of plant interactions as the focus in her lab. She noted that her current emphasis is on investigating fruit chemistry and their relations with seed predators, pathogens and dispersers. Her main areas of research are 1)the chemical ecology of seed dispersal and fruit defense, 2)plant evolutionary responses to multispecies interactions, and 3) causes and consequences of phytochemical diversity for plant interactions and 4) the consequences of domestication on defenses and interactions. Currenly her study systems are: a) Piper-bat interactions, b) apple domestication and resistance and c) Physalis interactions with herbivores and pollinators. Most of the time was spend discussing two of her current research proposals that were:

• Managing the apple phytobiome for enhanced fruit protection, nutrition and yield
• Sensory systems of fruits bats as a model for improving robotics in precision agriculture

The rest of the time was spend giving Susan feedback on the proposed projects and the granting agencies she could apply for.

9:50: Andre Kessler:

Andre gave an overview of his study systems, which include tobacco, goldenrod, tomato, maize (push-pull). Specifically funded by the multistate he has been working on the VOC-mediated information transfer and pest control. His lab has been working on how to manipulate information transfer between plants and their insect pests and how this can be applied in the field, where the information could be manipulated. He also presented work on the importance of SI (Silicon) on the inducibility of the secondary metabolisms in cucumber.

10:21: Jared Ali

Jared started presenting on the technology available in Penn State for volatile collection above and belowground. This was in order to promote collaboration with his lab and ensure that all members of this multistate group have a clear understanding of the equipment available and the type of analysis that can be performed in his lab.

He also presented on his research on how entomopathogenic nematode infestation can reduce the mass and oviposition of CPB feeding on a plant, which talks for the indirect effect of EPN mediated by VOC’s and not just the direct effect. In addition he presented research on how the odors of predators (Stinkbugs and ladybeetles) can prime the plants and affect plant-herbivore interactions. The application would be to induce plants both belowground and aboveground to affect herbivory. He also presented fascinating data on how the chitinases in the frass are affecting the induction of plants and how touching plants can also affect volatiles. He hereby showed that plants can be elicitated by non-conventional means, such as proteins in the frass (and not in the saliva), responses to “touch” and also responses to neighboring plants that have been “touched”.

His newest project presented shows how cover crops can affect Arbuscular Mycorrhizal Fungi (AMF) Communities and how the careful selection of those cover crops will allow to choose cover crops that facilitate the establishment of AMF while avoiding the use of those cover crops that inhibit the growth of those AMF.

11:00 Shadi Atallah

Shadi presented on his new multistate project that was born through the previous multistate meeting on “Bioeconomics of agrobiodiversity, pest control and pollinator health”. Shadi brings a completely different perspective to our meetings, since he is an economist, broadening our understanding of the implications that our research might have in terms of their economic impact. In their work they have been looking at the trade-offs between productivity, enabled through the extensive use of external inputs and pollination services. The main objective of the project is to determine if the use of neonicotinids as seed coating, while permitting the effective control of pests, could have a hidden costs due to their negative effects on pollinator health. This work that has also been expanded to an SCRI project led by Ian Kaplan, another member of this multistate group, where this tradeoffs between plant protection and pollination are observed throughout multiple states in different cucurbit plants. More recently in a project led by Katja Poveda, an in collaboration with Scott Mc Art, Brian Nault, Zsofia Szendrei and Ian Kaplan, we have expanded this idea to also include squashes that are so important in the North East. Shadi is currently building models to look at the effects of neonicotinoids depending on the spray, the run-off and the also natural habitats than can protect them from the insecticide use.

Shadi, through a proposal funded by this multistate, is also looking at the importance of variety biodiversity on the insurance value of agrobiodiversity in apple orchards. This project includes a model in which they design an optimal orchard spatial design that will minimize pest damage and the use of insecticides. The main idea is that by taking into account variety resistance and tolerance an optimal orchard can be designed that through its configuration will minimize damage and maximize productivity.

11:30 am: Kyle Wickings

Kyle talked about his program on the chemical ecology in the rhizosphere. His research focuses on how fungi collected from turf affect root herbivory by grubs. His results show that some fungi inoculations cause more feeding, but that Beauviera (entomopathogenic fungi) caused a reduction in root tissue removal by grubs compared to control plants. The roots of those plants have a higher carbon:nitrogen ratio.

 He also presented on his work on how herbivores can change the soil composition and how this understanding could help manage the use of neonicotinoids in turf. He hypothesizes that root herbivores are affecting the SOM content in the environment through their faeces and also through the root leftover that they leave after feeding on the plants. This extra SOM in the soil should increase the emission of CO2 and be attractive to ovipositing females, which should prefer those high SOM spots for oviposition and better larval development. Given that those hot-spots of grubs actually exists, if they can be identified through the emission of CO2 in the soil, it would be possible to detect future hotspots and just treat those spots with neonicotinoid, reducing more effectively and in a targeted manner pest pressure in turf. We discussed potential funding sources for this ideas and identified sources such as NSF: natural-human impacts: NSF CHN (Couples human-natural systems) as non-conventional sources that could be interested in funding this.

LUNCH:

This year for the first time we invited students, postdocs and visiting professors to our lunch to lead a discussion of the impact of context dependency on chemical-ecology tools for agriculture. Questions that were discussed were:

-How do we deal with context dependency of chemical ecology processes from the individual to the landscape scale? We realized that in the context of precision agriculture, it is very important to address the concept of context dependency, to be able to provide effective tools that can be implemented in different context. At the end of the lunch we concluded that the best approach to test this would be to set up a project across the US where we test the same approach (for example volatile induced responses, push-pull systems, pheromone traps, etc) across different sites in the US and monitor its context dependency.  We would repeat an experiment across multiple crops and multiple states. We would need to agree on one method and experiment that data can be compared across.

We thought that it would be ideal to pitch the idea to the McKnight foundation and explore other venues of funding such as the USDA-NIFA SCRI. Students and postdoc where very excited of being part of this discussion and overall this was seen as a positive outcome for everybody.

2:20 pm: Cesar Rodriguez-Saona

Cesar presented his research on how domestication can affect plant defenses against herbivores. His questions include: 1) Are there trade-offs between selection for high plant yield and defense? And 2) How does pathogen infection affect multi-tropic level interactions? He presented a case study on blueberry domestication and the preference and performance for Drosophila suzukii.

He also presented some more applied work on the use of semiochemicals (attractants, repellents, volatiles, pheromones) to manipulate insect behavior and reduce pest populations. For example they look at the effect of the phytoplasma (False Blossom Infection) on herbivores (vectors and non-vectors). In general the phytoplasma increases the preference for the herbivores, although the plants are doing really bad.From his experience he says that commercializing a “chemical ecology”solutions is really complicated and can be a complication for really making a difference

2:50 pm: Katja Poveda

Katja presented her work on overcompensation and more specifically how the damage in one generation can lead to an overcompensatory response in the next generation. There was a lot of interest in this, since it could be a solution for organic farmers who wan to improve tuber seed quality and yields. There was a discussion that this would be an ideal project to submit for an USDA-OREI, proposing it as a solution for organic agriculture to increase productivity.  

3:30 pm: Mike Mazourek

Mike presented on how work on the domestication of squash and  zucchini in organic farms and how to control pests in a sustainable way. The main pest he is trying to control is the striped cucumber beetles. He has been exploring how two varieties that are really different in their vulnerability for beetles, differ in their secondary metabolites. He has also been involved in outreach where he has been giving tasting and sustainability talks, that are very attractive to the public and he proposes this as a great way to reach a broader group of people and also to get more attention to how sustainability issued impact the food we eat.

Outputs: The most significant outputs has been the writing of research proposal based on preliminary data gathered since the establishment of this multistate project. For example for the project focused on the control of herbivores of cucurbits, two new projects have been submitted (see below) and one has already been approved for funding. New funded projects that originated from this multistate include projects concerned with the conservation of monarch butterflies, through a better understanding of the interactions with milkweeds and also Also projects investigating the trade-offs between crop protection and pollination services have been initiated that involve PI’s with expertise in pollination, abricultural economics, crop protection, landscape ecology and groecology. Manuscripts have been submitted and published during this time (for details see impact statement below). Most PI’s involved in this multistate have also disseminated their results at national conferences like the Ecological Society of America meeting and the Entomological Society of America meeting. PI’s have also interacted with farmers, and other stakeholders such a beekeepers and crop breeders, to start establishing means by which the performed research can be translated to tools and management strategies to protect pollinators, reduce pest pressure and increase yields. Outreach events that includes tastings of new varieties coupled with sustainability talks have also allowed to reach the general NYS public. Our collaboration with the Northeast IPM center has also rendered us a piece in their newsletter (http://www.northeastipm.org/about-us/publications/ipm-insights/plants-have-natural-defense-systems/) that describes the objectives of this multistate and allows us to disseminate the importance of tools based on chemical ecology for more sustainable crop production.

Activities:

• Related with our first and second objective, the project focused on controlling herbivores of cucurbits (lead by Mike Mazourek, Cornell University) has developed assays for the highly sensitive quantification of cucurbitacins using SPE concentration and LC-MS. This technique is used for sampling squash seedlings that define different taxonomic groups including inter and intraspecific comparisons that differ in their degree of damage by striped cucumber beetles. No differences were found for true leaves although they are most conspicuously damaged plant tissue in the field and further they were below the detection thresholds of the herbivore. Cotelydon differences aligned with beetle preference and were within beetle detection thresholds. This group hypothesized that beetle preference in squash is not determined by cucurbitacin concentration. To test this hypothesis, they exposed young seedlings of highly preferred squash (golden zucchini) and compared damage to non-preferred squash seedlings (summer squash). Comparisons were performed with either cotyledon or true leaves removed. In each experiment the beetles preferred golden zucchini tissue over the corresponding tissue in summer squash. The group interpreted this to mean that beetle feeding preferences are determined by another factor, other than cucurbitacins. This group has also adapted high resolution carotenoid separation methods to our HPLC system and calibrated it with known standards. Experiments are underway to look at carotenoid accumulation in different plant tissues that also exhibit preference differences by striped cucumber beetles.
• Regarding our second objective (Define variability of chemically mediated interactions between pests, crops, and beneficial organisms in terms of plant chemistry, species interactions and landscape factors in the Northeast), one group lead by Jennifer Thaler and Katja Poveda started a project measuring the relationship between potato plants, Colorado potato beetles and their predators on organic farms in Central New York. These farms were chosen to reflect a gradient from low-levels of agriculture to high levels of agriculture in the surrounding landscape. Preliminary data indicate that herbivore responses to predators depend on the landscape complexity. Jennifer Thaler’s group also investigated the defensive responses of Colorado potato beetles to stink bug predators using a population of beetles from Ithaca, NY. They have found large decreases in feeding and growth of beetles when predators are present but not consuming beetles. Combining these results is an advance in understanding the causes of variation in the predator-prey interaction and will be helpful in designing biological control practices in the future.
• In the front of pollinator research Lynn Adler has been leading an effort to understand how pollinator populations can be supported based on the quality of the host plants. This past year, they discovered that the medicinal value of sunflower pollen extends to a wide range of sunflower cultivars, wild sunflower accessions, two other Helianthus congeners, and even two Solidago species, which are in the same family as sunflower but not very close relatives. This discovery suggests that a wide range of sunflower relatives may be beneficial to the common eastern bumble bee and useful for treating Crithidia infection.
• The group lead by Richard Karban in this past year has learned how to make more effective use of volatile communication to induce resistance against insect herbivores. Specifically, they have learned that variation in the nutritional quality of crops can reduce the efficiency and success of herbivores across many different species of plants and insects. They also identified important sources of variation in plant quality in their model system for plant communication, Artemisia tridentata. Individuals vary in the major chemicals that they emit when they are attacked or damaged. This chemotypic variation affects how effectively they respond to cues of damage. The effectiveness of communication also is affected by the geographic proximity of the source of volatile cue, suggesting that plant cues may exhibit geographic dialects.
• Anurag Agrawal’s groups has been investigating ways to aid to the conservation of non-target organisms such as the monarch butterfly to agricultural practices, specifically the use of herbicides. Specifically they are investigating the use of swallow-worts by monarch butterflies, which are used for oviposition but do not support caterpillars. In this project they are investigating the use of swallow-worts by monarchs, the chemical cues used by monarchs to recognize them, and the impacts of reduced milkweed availability due to herbicide usage on their preferences. Initial experiments showed reduced oviposition on swallow-wort in the presence of milkweed. Chemical analyses are currently underway. 
• Cesar Rodriguez-Saona’s group at Rutgers has been applying chemical ecology techniques to understand the defensive traits of plants to the false blossom disease. Last year they evaluated the molecular and biochemical changes associated with plant defensive traits in cranberries affected by the false blossom disease and the preference and performance of its insect vector (blunt-nosed leafhoppers) and leaf chewers (spotted fireworm, Sparganothis fruitworm, and gypsy moth) on plants infected by false blossom disease.
• This same groups has been very active at development management tools based in behavior-manipulation to control the invasive pest spotted wing drosophila (SWD) in blueberries. These studies involved the use of attracticidal red spheres that incorporate a toxin, a phagostimulant, and a visual stimulus. Experiments were conducted to evaluate: a) the effects of pattern of placement of spheres within fields (grid versus border) in reducing SWD infestation, and b) the effects of location of spheres within a bush (top versus bottom) in reducing SWD infestation. Studies were also conducted using a new sprayable attract-and-kill formulation, SPLAT SWD, to reduce SWD infestation. SPLAT SWD was applied alone or in combination with organic insecticides in blueberry fields. In addition studies were conducted to investigate the response of SWD to odors from various sources including fermentation, yeast, and leaves. These studies were conducted under laboratory and field conditions.
• The group of Andre Kessler studied how biotic and abiotic environmental factors influence chemical information transfer and plant secondary metabolism-mediated interactions with other organisms. This past year, they focused on three key projects, namely A) the effects of temperature and humidity on the information : noise ratio in volatile organic compound (VOC) signaling, B) the effects of certain soil elements, such as As and Si on constitutive and inducible plant secondary metabolism and herbivore resistance, and c) the role of VOC signaling on mediating complex community dynamics and plant fitness outcomes. One major finding from the Datura wrightii study system is that the emission of certain plant VOCs is primarily altered by abiotic stresses, while others are emitted specifically in response to biotic stresses, such as herbivory. This means that VOC-mediated chemical information is encoded in distinct channels allowing interacting organisms to very specifically extract information about the plant’s physiological and metabolic status. In another study with cucumber, the group found a major induced resistance-mediating effect of Si. Plants grown in soils with minimal Si-content were not able to induce resistance in response to herbivore attack. Current work focuses on the effects of Si on direct and indirect resistance traits as well as the mechanisms underlying the priming effect. Lastly, research associated with this Multistate project that focused on modeling chemical information transfer revealed VOC-mediated chemical information transfer has a stabilizing effect on community dynamics.

Milestones reached:

As a group we have reached several milestones pertaining to our different objectives. Most activities have been focusing on defining the variability of chemical mediated interactions between pests, crops and beneficial organisms in terms of plants chemistry, species interaction and landscape factors in the Northeast (Objective 2). Here we have an overall better understanding of which chemical cues are mediating interaction between cucumbers and their herbivores, how the landscape is shaping interaction between crops, herbivore pests, and predators, how plant quality can affect pollinator health and how the quality of the crop influence their interactions with herbivores. Regarding our second objective on developing chemical ecology tools and information to support sustainable agriculture by reducing damage by pests in crops such as potatoes, brassicas, cucurbits, apples, blueberries, and sweet corn, while maintaining pollinator health in agricultural systems we have definitively started to identify the main chemical cues that are involved in important interaction between plants and their pests or vectors of important diseases. Mostly for blueberry there are promising tools that can help control Spotted wing Drosophila, while other information could be used to hopefully be soon used as tools for more sustainable agriculture. Our 5^th objective of establishing a chemical ecology analytical facility in the Northeast definitively has progressed. Embedded in our presentations PIs overseeing chemical equipment have been talking about the current facilities making those equipments available for others and providing a good underatsnding of which type of analysis can be done in the different labs. The shared expertise among members of this multistate have allowed for the availability of shared equipment across the NE, fulfilling this objective.

Training

Several postdocs, technician and PhD students have been trained on this project. They are not just receiving training on the chemical ecology of plant interactions and their potential use for sustainable agriculture, but also receiving substantial professional development.

Planned activities for the next year

In the coming year, several groups (Mike Mazourek, Jennifer Thaler, Andre Kessler, Lynn Adler, Cesar Rodriguez, Anurag Agrawal) will finalize the analysis of their initial results and write those for publication. We anticipate that at least 7 manuscripts will be send out for publications derived from the data obtained this year. Also grant proposal will continue to be written based on preliminary data generated in the course of this multistate. We also anticipate that more concrete work with stakeholders such as organic farmers will allow us to submit a larger OREI proposal and that we will start implementing some of the gathered information in form of concrete tools or management practices on farms to support more sustainable agriculture (Objective 1). We will continue developing all proposed objectives, given that new funding was given to groups that are interested in characterizing the non-target effects of pesticides on pollinators, covering our goals proposed in objective 3. All groups that have obtained funding through this multistate will also present the results to the research community at national meetings and will disseminate their work also at local farmer meetings.

Vannette RL and Fukami T, Contrasting effects of yeast and bacteria on floral nectar traits, Annals of Botany, accepted.

Rering C.C, Beck J.J., Hall, G., McCarthy, M., Vannette RL, Nectar-inhabiting microorganisms influence nectar volatile composition and attractiveness to a generalist pollinator. New Phytologist (early view) doi: 10.1111/nph.14809.

Glaum P. and A. Kessler. 2017. Functional reduction in pollination services through Herbivore-Induced Pollinator Limitation and its potential in mutualist communities. Nature Communications. in press

Claflin, S, Jones, L, Thaler, J, Power, A. 2016. Crop-dominated landscapes have higher vector-borne plant virus prevalence. Journal of Applied Ecology. 10.1111/1365-2664.12831

Lauren Brzozowski and Michael Maozurek. Sustaining the future of horticultural crop production through organic agroecological pest management. Sustainability. Accepted.

Brevik, K., S. D. Schoville, D. Mota-Sanchez, and Y. H. Chen. 2018. Pesticide durability and the evolution of resistance: A novel application of survival analysis. Pest Management Science 10.1002/ps.4899.

Schoville, Sean D., Y. H. Chen, M. N. Andersson, J. B. Benoit, A. Bhandari, J. H. Bowsher, K. Brevik, K. Cappelle, M-J. M. Chen, A. K. Childers, C. Childers, O. Christiaens, J. Clements, E. N. Elpidina, P. Engsontia, M. Friedrich, I. García-Robles, C. Goswami, A. Grapputo, K. Gruden, M. Grynberg, B. Henrissat, E. C. Jennings, J. W. Jones, M. Kalsi, S. A. Khan, A. Kumar, F. Li, V. Lombard, X. Ma, A. Martynov, N. J. Miller, R. F. Mitchell, M. Munoz-Torres, A. Muszewska, Brenda Oppert, S. R. Palli, K. A. Panfilio, Y. Pauchet, L. C. Perkin, M. Petek, M. F. Poelchau, E. Record, J. P. Rinehart, H. M. Robertson, A. J. Rosendale, V. M. Ruiz-Arroyo, G. Smagghe, Z. Szendrei, E. M. Szuter, G. W. C. Thomas, A. S. Torson, I. M. Vargas Jentzsch, M. T. Weirauch, A. D. Yates, G. D. Yocum, J-S Yoon, Stephen Richards. 2018. A model species for agricultural pest genomics: the genome of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae). Scientific Reports 8: 1931.

Brevik, K., L. Lindström, S. D. McKay, and Y. H. Chen. 2018. Transgenerational effects of insecticides – implications for rapid pest evolution in agroecosystems. Current Opinion in Insect Science. Special Issue, “Ecological Adaptation in Agroecosystems”.

Izzo, V., Y. H. Chen, S. D. Schoville, C. Wang, D. J. Hawthorne. 2018. Origin of pest lineages of the Colorado potato beetle, Leptinotarsa decemlineata. Journal of Economic Entomology.

Crossley, M. S., Y. H. Chen, R. L. Groves, and S. D. Schoville. 2017. Landscape genomics of Colorado potato beetle provides evidence of polygenic adaptation to insecticides. Molecular Ecology DOI: 10.1111/mec.14339

Alyokhin, A. and Y. H. Chen. 2017. Adaptation to toxic hosts as a factor in the evolution of insecticide resistance. Current Opinion in Insect Science 21:33-38.