Progress 10/01/17 to 09/30/20
Outputs
Target Audience:The target audience of this work is primarily forest managers and forest health professionals. My lab also seeks to engage with local schools and to advocate for heathy forests with the general public whenever possible. I have incorporated multiple aspect of this researching in both my Forest Health and my Forest Entomology course (aimed at Forestry, Environmental Science, and Wildlife majors). Through these courses, this work has reached approximately 100 students including undergraduates and graduate students. Practicing foresters are a key audience for education on impacts and management of beech bark disease (BBD) on New Hampshire forests, and I have shared this work through the UNH Silvicultural Institute reaching ~80 foresters over two workshops. While beech bark disease is widespread in the northeast region and has dramatic impacts on cultural, economic, and aesthetic value of forests, the general public are often less aware of slow-moving decline diseases like BBD than more dramatic events such as Chestnut blight, Dutch elm disease, or the emerald ash borer invasion which have the potential to remove entire tree species from the landscape. In order to increase awareness in the general public of the impacts of BBD and similar diseases I have given radio interviews on New Hampshire Public Radio's 'The Exchange' program. Changes/Problems:This project has been highly successful and has formed an important pillar of my research career at UNH. Our research outputs are novel and highly likely to have significant impact on researchers' collective understanding of this important disease and how to manage it. Our original timeline was to publish our results in early 2020. While we did publish one paper with collaborators linked to this work in accordance with this timeframe, publication of the core results has been delayed by approximately 8-9 months due to unexpected shutdowns caused by Covid-19. What opportunities for training and professional development has the project provided?This work has directly supported student and postdoctoral mentoring including one MSc student (Ken Windstein) and two postdocs (Jeremy Heath and Eric Morrison). Ken and I have shared this work with the local elementary school several times on various fungus, forest, and insect walks/discussions. Postdoctoral researcher Eric Morrison has applied for a NIFA Fellowship to continue and expand on this work and to further develop his career and research portfolio. In terms of professional development Eric has lectured on diversity and function of plant-associated microbes in my upper-level undergraduate and graduate-level Forest Health class, providing an opportunity to expand his teaching repertoire in terms of both development of teaching materials and presentation to upper-level students. He has also worked closely with Ken to develop and execute aspects of Ken's MSc project, providing experience in mentoring grad students. Eric has had numerous training opportunities in research including implementing de novo whole-genome sequencing using a MinION sequencer - a first for both him and my lab, and developing bioinformatic pipelines for quality control and genome assembly using this data in combination with Illumina HiSeq sequence data. He participated in a multi-institution course on population genetics data analysis supplementing his statistical and analytical repertoire, and has led manuscript development providing practical experience in research dissemination. How have the results been disseminated to communities of interest?We have presented this work as a poster at the Mass Myco meeting at Harvard in 2018, at the Northeastern Forest Pest Council meeting in Portland, ME in 2020, and at the Mycological Society of America meeting, also in 2020. These meetings reach a variety of audiences including the regional academic mycological research community, practitioners and academics in forest health in the northeast region, and the national mycological research community, respectively. I have also twice share content with foresters via UNH's Silvicultural Institute which practicing foresters (approx. 80 over two years) attend for continuing education credits as a criterion of professional certification. I have twice been a guest on New Hampshire Public Radio's Laura Knoy "The Exchange" program where I shared some of this research in an interview/call-in Q&A format. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The NHAES-funded beech bark disease project at the University of New Hampshire focuses on understanding the fungal infection dynamics and interactions with an invasive scale insect in the context of variable microbial communities, climates, and infection durations of this important forest disease. Beech bark disease (BBD) is a major problem for forest managers throughout eastern forests. Despite elevated mortality especially among large American beech (Fagus grandifolia) trees, beech has maintained or even increased in relative basal area within infected forests, owing to aggressive recruitment by seedling and root sprouts and a decades-long period of lower susceptibility in small stems. Together, these factors result in a smaller, denser forest over time in the presence of BBD with substantial reductions in resources for wildlife (i.e., abundant seed crops and cavity nesting opportunities for many birds and mammals, including deer, bear, and turkey) and aesthetics. In addition, beech regularly outcompetes more valuable species such as sugar maple leading to reduced timber values and stand diversity. Despite decades of study, relatively little is known about the pathogen infection dynamics or other microbes associated with disease, particularly in the context of interactions with the scale insect initiating agent and as they vary across the range of the disease. We assessed bark microbial communities across the range of BBD by first collecting over 212 bark samples from ten sites across eight states, extracting whole environmental DNA from a subset of these samples, and then sequencing a specific gene region (ITS2, part of the Internal Transcribed Spacer region of the ribosomal DNA) using fungal-specific primers. After bioinformatic processing, we identified 1339 unique sequence variants, roughly equivalent to 796 fungal taxa. This work clearly demonstrates a high degree of co-infection with both known BBD pathogens (Neonectria faginata and N. ditissima) and has elucidated a potential role for multiple other microbes that could be important in this system, either as cryptic pathogens or as pathogens or parasites of the disease agents themselves. Further, we identified nine fungi statistically associated with healthy beech trees - including known insect pathogens and parasites of other fungi - that may aid in warding off onset of disease (i.e., beneficial microbiome).Inaddition, we instituted an extensive field experiment where we established different densities of scale insects on trees (across two sizes and multiple bark types) and inoculated with one or both Neonectria species. Data from this experiment have been captured and are currently being analyzed. Taken together, this work has a strong potential to increase our understanding of complex interactions among causal agents of disease and will offer strategies for mitigation, including a more nuanced assessment protocol for selecting resistant trees in the landscape. For example, through this project we have identified several fungi that appear to be acting as antagonists to disease in this system. Several known "mycoparasites" (fungi that feed on other fungi) were found and their distributions mapped. Several appear to respond to disease but are relatively rare across the range of BBD, which presents the opportunity of augmentative biocontrol should they be found capable of suppressing Neonectria. Several potential pathogens of scale insect were also uncovered including Fusarium babinda which is widely associated with the disease complex and could be mitigating infection severity under certain environmental conditions. This and other fungi could again be augmented or promoted using management, pending further research. Finally, this work has cleared up the long-standing mischaracterization of Neonectria ditissima as a rare and minor player in the BBD pathosystem, which primarily has been thought of as only relevant in the advancing from of the disease. We found this fungus to be present in almost 30% of diseased trees (> 15 times higher than early estimates of 1-2% within aftermath forests). In most cases, this fungus co-occurs with the dominant N. faginata in the same tree and even within the same 1cm phloem disk. The consequences of coinfection in the BBD complex is currently under study but theory predicts - and empirical evidence from other systems supports - important ecological and evolutionary consequences of coinfection. During this work we have also sequenced the N. faginata genome and are currently exploring single nucleotide polymorphisms (SNPs) which can be used to examine population structure, movement and spread history, and has already yielded new knowledge of reproductive strategies and mating type genes in this group of fungi, published in 2020. This latter work led to the rejection of a key hypothesis explaining the relative dominance of N. faginata in the BBD system. Reconstruction of the colonization history and current population structure of the BBD pathogens likewise has implications for management. For example, if there is strong population structure and/or evidence of local adaptation could mean that management approaches (e.g., the augmentation of mycoparasites, discussed above) might function differently in different regions. Strong population structure would also impact predictions regarding how these pathogens are likely to respond to changing climate and environmental conditions. Finally, the genome sequence and associated resources emerging from this work (i.e., functional gene annotations, identification of mating type loci, SNP discovery for population genomic and genome-wide association [GWAS] studies, etc.) represents an invaluable resource. Specifically, this could facilitate the identification of virulence factors and the elucidation of host pathogen interactions. Together with the recently sequenced beech, this work also represents a significant step forward in identifying genes associated with resistance to BBD (and to its component organisms) which could greatly enhance our ability to select for and/or cultivate and breed trees that will maximize the health of the species and beech-dominated forest going forward. The specific objectives of this project were to 1) characterize and assess fungal communities of importance to disease dynamics across the range of BBD, and 2) to examine the frequency of co-occurrence and co-infection of the two dominant pathogens (N. faginata and N. ditissima) as well as the impact of spillover from non-beech hosts for the latter pathogen. Both of these objectives have been accomplished during the course of this work. We have presented results from both objectives at several scientific conferences and are very close to submitting this work for peer-review and publication. The first of 4-5 publications (3 from postdoc Eric Morrison and 1-2 from Master's student Ken Windstein) is nearing submission having been delayed significantly by COVID-19. Data acquisition and processing is complete for three of these publications - this work will be submitted within the next several months. We also instituted a replicated field study where we manipulated scale insect densities and performed inoculations of N. faginata, N. ditissima and both species combined on randomly selected beech trees across size class and bark structures (both factors are relevant to disease susceptibility and progression and to ecological feedbacks among interacting disease agents). Results of this work is forthcoming and addresses related objectives to examine host tree effects on disease expression. In 2018 I submitted an NSF proposal to augment this work by instituting common gardens to test pathogenicity while controlling for host genetic background. While this work has not yet been funded, I am already working with collaborators to submit a revised proposal to NSF and to the AFRI Foundational program in early 2021.
Publications
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2018
Citation:
Morrison, E., Heath, J. J., and Garnas, J. R. 2018. Bark microbial communities as drivers or mitigators of beech bark disease in eastern North America. Mass Myco 2018, Harvard University. Poster. https://massmyco.wordpress.com/program/posters/
- Type:
Journal Articles
Status:
Published
Year Published:
2020
Citation:
Stauder, C. M., Garnas, J. R., Morrison, E. W., Salgado-Salazar, C., and Kasson, M. T. 2020. Characterization of mating type genes in heterothallic Neonectria species, with emphasis on N. coccinea, N. ditissima, and N. faginata. Mycologia 112:880-894. 10.1080/00275514.2020.1797371
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2020
Citation:
Windstein, K. and Garnas, J. 2020. The Knotted Beech: An Investigation of Interactions and Feedbacks between Beech Bark Disease Agents, Bark Microstructure and Host Tissue Responses. NEFPC Annual Meeting: a joint meeting between the Northeastern Forest Pest Council & Northeast Forest Fire Compact, Portland, ME. Presentation.
|
Progress 10/01/19 to 09/30/20
Outputs
Target Audience:The target audience is primarily forest and land managers and forest health professionals, though serving and educating the general public is always a primary goal. This work has been shared informally with members of the State of New Hampshire Department of Forests and Lands. Our presentation at the Northeastern Forest Pest Council meeting also reached numerous (~200) foresters/land managers and forest health advocates and practitioners. Changes/Problems:COVID-19 did result in a major shutdown at UNH and led to a delay in the processing of our sequences by the Hubbard Genome Center by over six months. Despite this setback we were able to accomplish project goals, though final publication of this work was slightly delayed as a consequence, with 3 papers currently forthcoming and 2 more pending the completion of an associated Masters project. What opportunities for training and professional development has the project provided?This work provided training and mentorship to postdoc Eric Morrison around bioinformatics and associated community analysis and for MSc student Ken Windstein. One PhD student and two undergraduate research technicians were also trained and acquired valuable experience in association with this project. PI Garnas likewise developed additional skills in bioinformatics and participated in a Landscape Genomics course which proved invaluable. This work was highlighted in PI Garnas' Forest Health (~18 undergraduate and postgraduate students) and Forest Entomology (14 undergraduates) courses. Two groups totally six students chose topics related to beech bark disease for their final independent research projects. PI Garnas also served on a Masters committee for a student at SUNY-ESF studying this disease on the context of experimental nutrient (nitrogen and phosphorus) additions which has led to budding collaborations and several publications in development. How have the results been disseminated to communities of interest?Part of this work was published in a peer-reviewed topical journal (Mycologia) and shared via a student talk at the Northeastern Forest Pest Council meeting in Portland, ME and as a virtual poster in association with the Mycological Society of America meeting. Both MSc student Windstein and PI Garnas presented aspects of this research to a local elementary school (3rd grade) as part of their "Tree Trekker" science curriculum. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
In this third year of the NHAES-supported project, we completed analysis and interpretation of sequencing data in support of Objectives 1 and 2. Specifically, we now have a strong understanding of fungal communities associated with beech bark disease (BBD) across the range of this important forest disease. This includes the characterization of known BBD pathogens as well as antagonists of BBD development together with their relative frequencies on trees and within individual cankers. In addition, we characterized broader communities what allow for the assessment of other potentially important interacting species in the system, including other pathogens heretofore not know to be present. Taken together, these community data allow for the assessment how microbial taxa within beech bark change as a function of disease severity, duration of infection, and across geography. This year we also instituted a comprehensive field trial where we manipulated the major players of disease development and aggressiveness (i.e., scale insects and the two Neonectria pathogens) across tree sizes and bark types. This represents an important first step toward developing a more nuanced understanding of the role of host (i.e., bark type, age), and current infection status on pathways and severity of symptom development and pathogen aggressiveness on trees. Taken together, this work will aid forest managers in selecting trees for removal v. preservation and may suggest avenues for disease mitigation. Specific Objectives 1. Characterize the relative frequency of BBD fungal associates (N. ditissima, N. faginata and B. ochroleuca), the fungal parasites Gonatorrhodiella highlei and other known mycoparasitic fungi, and fungal endophytes in the bark and phloem of beech using targeted culturing and high-throughput amplicon sequencing. This sampling is complete and we are in the final stages of analysis. Interesting finding include a) the high rate of co-infection by BBD pathogens and non-random biogeographic distributions of these species); b) the frequent identification of microparasitic (fungus-infecting) and entomopathogenic (insect-infecting) fungi as well as a handful of the potential pathogens present in the system that could be influencing disease expression. 2. Examine patterns and consequences of co-occurrence among fungal BBD agents at multiple special scales (i.e., within sites, trees, and local infections [coalescing cankers]), and to determine the effects of spillover of N. ditissima (BBD-associate that causes target canker on a variety of hardwood hosts) on co-occurring species across the range of BBD. Our sequencing efforts have elucidated patterns with respect to co-occurrence and co-infection and our field experiment will offer experimental results with respect to the consequences of pathogen diversity on aggressiveness. Objectives 3 and 4 were included in our initial proposal as examples of directions that could be pursued should additional funding become available. In 2020, several collaborator meetings were organized to development an NSF funding proposal to be submitted in early 2021. That said, progress toward the general objective of understanding the role of host and host condition was made via the implementation of our field experiment where we removed and then readded two densities of scale insect and inoculate bark with both pathogens (independently and in a mixture) on 80 trees (plus 40 saplings) in the Durham area. This will provide insight and inference concerning the nature of interactions between disease agents and host trees as well as among disease agents themselves.
Publications
- Type:
Journal Articles
Status:
Accepted
Year Published:
2020
Citation:
Stauder, C. M., Garnas, J. R., Morrison, E. W., Salgado-Salazar, C., and Kasson, M. T. 2020. Characterization of mating type genes in heterothallic Neonectria species, with emphasis on N. coccinea, N. ditissima, and N. faginata. Mycologia 112:880-894. 10.1080/00275514.2020.1797371
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2020
Citation:
Windstein, K. and Garnas, J. 2020. The Knotted Beech: An Investigation of Interactions and Feedbacks between Beech Bark Disease Agents, Bark Microstructure and Host Tissue Responses. NEFPC Annual Meeting: a joint meeting between the Northeastern Forest Pest Council & Northeast Forest Fire Compact, Portland, ME. Presentation.
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2020
Citation:
Morrison, E., and Garnas, J. R. 2020. Patterns and drivers of occurrence of Neonectria faginata and N. ditissima across the range of beech bark disease Mycological Society of America Annual Meeting, Virtual poster
|
Progress 10/01/18 to 09/30/19
Outputs
Target Audience:Ultimately, the goal of this project is to provide basic and applied research to inform management of American beech in the face of beech bark disease (BBD), and exotic insect-native fungi interaction that is responsible to the loss and disfigurement of many large beech trees and for the production of thickets of small beech stems. Thus, I anticipate the forest managers, agency (i.e., US Forest Service staff), and landowners will be key components of the target audience. In the interim, however, the current project has been an excellent teaching tool for undergraduates and postgraduates. I present field and lecture-based curricula based on this project to both my Forest Health (cross-listed undergraduate/graduate course, NR 782/882, 20 and 21 total students in 2019 and 2020 respectively) and to my Forest Entomology course (NR 506, 9 undergraduate students in 2019). The project provides an avenue for exploration and discussion around topics including biological invasion, insect-fungal interactions and forest health, genetics and genomics, breeding, and forest management in the face of an exotic pathogen complex. Partly as a consequence, one or more student groups (3-5 students total) choose beech bark disease as the topic of the final project and report. Changes/Problems:The most significant delay we have experienced was due to the departure of a former postdoc (Dr. Jeremy Heath). Dr. Heath was instrumental in building the fungal and tree bark collections that underpin this work. Current postdoc Morrison has now fully integrated into the lab and is an excellent addition to our team. That said, this change in personnel likely set the project back by approximately 4-6 months. Additionally, plans to collect Neonectria ditissima on non-beech hosts proved harder to implement than we'd originally thought. We will augment the collection of this fungus via field sampling this winter and Spring. No changes in the overall goals or outcomes of the project over the anticipated three-year funding life cycle of anticipated. What opportunities for training and professional development has the project provided?This project has facilitated the training and mentoring of a postdoc (Eric Morrison), a new MSc student (Ken Windstein), and several undergraduate technicians. Eric Morrison presented a poster at the Massachusetts Mycological Society (MassMyco) held at Harvard University in late 2018, and is preparing several abstracts for conferences in the current project year. Ken Windstein and PI Garnas had the incredible privilege of spending a day in the field and in discussions with retired researcher and worldwide expert on beech bark disease, Dave Houston. How have the results been disseminated to communities of interest?As stated, we presented early results from our field sampling and genetic characterization of bark communities at the MassMyco meeting at Harvard University (https://massmyco.wordpress.com/) To date, our results are still preliminary and have primarily been shared directly with collaborators and with other interested researchers via discussion and presentations. Though this is a relatively small meeting with ~60 attendees, it is an excellent opportunity for cross-pollination between amateur naturalists and concerned citizens and practicing scientists. I was so impressed with the tenor and possibilities that I volunteered as a member of the Steering Committee and will help strategize and facilitate future meetings in the Northeast region. The project is now progressing into a phase where broader results and data sharing will become a primary goal, via publication, presentations at national conferences, and direct reporting to agencies such as the U.S. Forest Service. What do you plan to do during the next reporting period to accomplish the goals?We have recently processed and produced "metabarcoding" libraries for 225 fungal community bark samples and submitted them for sequencing on an Illumina HiSeq at the University of New Hampshire's Hubbard Genome Center. Once processed bioinformatically and as a function of our ecological variables, we will have a full characterization of bark fungal communities as they vary geographically, bytime since infection with beech bark disease, as well as how the co-vary with disease symptoms. This is a large task but will soon result in a very comprehensive understanding of pathogen distribution and co-occurrence, as well as patterns of co-occurrence with fungal "enemies", competitors, and other endophytes of potential importance, as laid out in the Objectives. Additionally, we will score fungal growth rates and damage in our inoculation experiment on large trees with variable scale insect densities as well as on saplings. A major goal this coming year will be to acquire additional funding to supplement and augment key aspects of this work.
Impacts
What was accomplished under these goals?
We advanced considerably during the reporting period by building baseline knowledge, understanding, and methods for working with beech bark disease as an experimental system in New Hampshire and beyond. The impact of this work is still developing but already key findings appear promising for modified management of this important disease complex.For example, recent results of our extensive fungal collection and sequencing efforts have been the discovery of a considerably larger role for the generalist pathogen (Neonectria ditissima) in the beech bark disease complex than was previously recognized. The finding changes our understanding of basic disease epidemiology. Specifically, it implicates the potential importance of alternate trees of this generalist pathogen on disease dynamics.We still need to confirm and further explore this result and elucidate the scope of the pattern at a geographic scale. In light of this finding we have performed replicated, controlled field inoculations of different strains and species into American beech, as well as several combinations therein. This represents a first step toward building a protocol for examining tree resistance and susceptibility to the fungal component of this insect-fungal disease interaction and will allow us to examine the relative pathogenicity of the dominant pathogens in this system. In the next year, we plan to publish these novel findings in peer-reviewed journals as well as to share them with various stakeholders. Progress relative to specific objectives follows: Objective 1. CHARACTERIZE THE RELATIVE FREQUENCY OF BBD FUNGAL ASSOCIATES (N.DITISSIMA,N.FAGINATAANDB.OCHROLEUCA), THE FUNGAL PARASITESGONATORRHODIELLAHIGHLEIAND OTHER KNOWN MYCOPARASITIC FUNGI, AND FUNGAL ENDOPHYTES IN THE BARK AND PHLOEM OF BEECH USING TARGETED CULTURING AND HIGH-THROUGHPUT AMPLICON SEQUENCING. Collections of beech bark and phloem werebeen made from 20 sites across eight states in 2017 and 2018. We extracted DNA from 212 F. grandifolia phloem samples representing whole fungal endophyte communities, including N. faginata and N. ditissima when present. A subset of these same samples has served as the source material for culturing of single-spore isolates to ultimately be used for population genetic work and for fungal challenge assays (Objective 2 and ultimately for Objective 4). Whole-fungal community DNA was amplified using polymerase chain reaction (PCR) for amplification of the ribosomal internal transcribed spacer two (ITS2) fungal marker gene region, which is the most commonly used genetic marker for fungal species identification. A preliminary sequencing run was performed using these 212 samples in addition to various controls, resulting in 105 samples with sufficient sequencing depth for downstream analyses. The full dataset was submitted for re-sequencing in September 2019. These results have already revealed a higher incidence and abundance of N. ditissima, previously thought of as rare in the beech bark disease system, including numerous occurrences of co-infection by both species of Neonectria. We also successfully identified at least one parasite of the pathogenic fungi in the BBD system, which could have relevance for the management and suppression of the disease. This work will improve our knowledge greatly around the geographic distribution and relative importance of two morphologically and ecologically very similar pathogens. It will also be the first characterization of endophytic bark communities in the BBD system which can likewise have a protective effect on trees in the face of a virulent disease. EXAMINE PATTERNS AND CONSEQUENCES OF CO-OCCURRENCE AMONG FUNGAL BBDAGENTS AT MULTIPLE SPATIAL SCALES (I.E., WITHIN SITES, TREES, AND LOCAL INFECTIONS [COALESCING CANKERS]), AND TO DETERMINE THE EFFECTS OF SPILLOVER OF THE GENERALISTN. DITISSIMAFROM NON-BEECH HOSTS. We established experimental trees with augmented populations of thefelted beech scale insect (Cryptococcus fagisuga). Thi insect is the initiating agent for BBD and is required for subsequent colonization of phloem tissue by Neonectria spp. Populations were augmented to two different levels (low and high) by placing between 500 and 1500 eggs on trees beneath protective foam. These trees were then challenged with 6mm plugs of either or both Neonectria pathogens in a replicated, randomized block design. Additionally, 80 saplings were challenged with the same strains of Neonectria in order to characterize baseline levels of pathogenicity of the different species and strains. The artificial inoculations are currently incubating and lesion size and necrosis will be characterized in Spring 2020. Additionally, we are in the process of testing the influence of pathogen identity and co-occurrence on disease symptom severity across the range of our collections. This work will help us to better understand whether fungal pathogen species identity and/or patterns of co-occurrence among the two dominant pathogens is an important determinant of disease aggressiveness, with potential consequences for management. TO PERFORM LABORATORY ASSAYS OF QUANTITATIVE OR QUALITATIVE RESISTANCE TO BBD AGENTS (BOTH SCALE INSECTS AND STRAINS OFNEONECTRIASPECIES) UNDER GREENHOUSE CONDITIONS USING HALF-SIB BEECH FAMILIES COLLECTED FROM ADVANCING FRONT, AFTERMATH, AND UNINFECTED FORESTS. This Objective was addressed using field assays as the collectionof beech seed is best performed in a mast yearwhich did not coincide with our field collections. However, there are some advantages to carrying out this work on larger trees in forested conditions. First, the augmentation of scale insect population as described in Objective 2 (above) strongly impacts fungal infection dynamics and so mimic typical conditions more slowly. Our sapling challenges assays described above serve as a useful scale insect-free control for our experimental inoculations. This work will allow us to characterize tree resistance to scale insect and to the two Neonectria pathogens -- alone and in combination - as well as cross-resistance (or lack thereof) to insects and fungi. This knowledge could inform management by helping to define optimal tree selective removal and/or breeding strategies in the face of this ongoing disease. TO ESTABLISH AND MONITOR AT LEAST TWO COMMON GARDENS COMPRISING BEECH FAMILIES (COLLECTED AS IN OBJECTIVE 3) TO EXAMINE HERITABLE GENETIC VARIATION IN SUSCEPTIBILITY TO SCALE INSECT AND FUNGI ASSOCIATED WITH BBD TOGETHER WITH THE ENVIRONMENTAL (E) AND GENE-BY-ENVIRONMENT (GXE) COMPONENT.Objective 4 represents a longer-term vision for which we are currently seeking additional funding. In March and July 2019, I organized conference calls with key collaborators to advance ideas around this funding application which I intend to submit to the National Science Foundation in the first half of 2020. The creation of a common garden network would be an extremely powerful approach toward truly understanding genotypic, environmental and genotype-by-environment effects on disease expression.
Publications
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2018
Citation:
Morrison, E., Heath, J. J., and Garnas, J. R. 2018. Bark microbial communities as drivers or mitigators of beech bark disease in eastern North America. Mass Myco 2018, Harvard University. Poster. https://massmyco.wordpress.com/program/posters/
|
Progress 10/01/17 to 09/30/18
Outputs
Target Audience:The target audience for this work, in addition to the scientific community,is primarily foresters and land managers at the state and federal level, as well as researchers who are in a position to implement novel mitigation strategies for control and suppression of beech bark disease across the range of the disease (Maine to North Carolina and west to Wisconsin). Preliminary findings from this work have been presented in the following fora: MassMyco (Massachusetts Mycology) bi-annual meeting where it reached approximately 100 regional scientists with interests in fungal biology (including tree pathogens) as well as amateur mycologists. As a consequence of this meeting, PI Garnas is now on the society's Steering Committee and will help plan the meeting in 2020. Forest Health (NR782/882), an advanced undergraduate/graduate course (18 students). This work was presented and explored on several occasions during lectures, indoor and outdoor labs, and it informed and inspired one of the final student group projects. Forest Entomology (NR506), 25 undergraduates. Work was presented during two lectures focusing on scale insects and insect-microbe interactions respectively. Silvicultural Institute (pine-hemlock-oak), UNH-run 2-day forester training workshop. Reaches approx. 200 participants working in forestry and land management in New England University of Maine Biology weekly seminar, approximately 50 attendees. PI Garnas presented topics that included AES work. Current results are preliminary, and we have not processed the full suite of samples to identify associated fungal communities. I anticipate that solid results will begin to emerge and be finalized in early-mid 2019. Efforts to share key findings will commence from there. Changes/Problems:Overall, progress in this first year was good. We did have a moderately serious mite infestation and lost some cultures which have since been re-isolated. As a long-term solution we have moved our fungal culturing operations to a new lab space and have implemented new, more stringent protocols around culture maintenance and mite control. What opportunities for training and professional development has the project provided?Two undergraduate student workers have received significant training and exposure fungal culturing and genetic sequencing as part of this project to date. How have the results been disseminated to communities of interest?As discussed in the "Target Audiences" section of this report, our preliminary results to date have been incorportated into various undergraduate, graduate, and professional courses at UNH and via seminars and a poster presented to scientific and "amateur" audiences respectively. Once our results and associated management implications are ready and assembled they will be disseminated via multiple channels (social media, UNH extension, reports and other media shared through forester and land manager networks, etc) in an attempt to reach the target audience as fully as is feasible. What do you plan to do during the next reporting period to accomplish the goals?The principal focus of the upcoming year is to complete the culturing from all bark samples so as to build a comprehensive culture collection of Neonectria fungi. Following this (nearly completed) task, we will process all bark samples using a metabarcoding approach on the Illumina HiSeq using already-developed pipelines and protocols. We will then model patterns of pathogen/endophyte community richness and composition as a function of a suite of landscape predictors (climate, tree species composition, beech basal area, etc.) in service of Goal 2. Additionally, we will submit 1-2 funding proposals to transition this work and the data it produces into a larger-scale project which includes beech common gardens which can be assayed against key pathogen strains to reconstruct geographic patterns and changes in tree resistance as a function of the duration of infection with beech bark disease. We anticipate publishable results from this work by the end of 2019 which will be shared broadly.
Impacts
What was accomplished under these goals?
Ultimately, this goal of this project is to enhance understanding of the role of the fungal endophyte and pathogen community diversity and composition around an important forest disease (beech bark disease) and to apply this knowledge toward improved breeding and management to mitigate beech bark disease impacts on the North American landscape. Effective beech bark disease mitigation would significantly improve forest ecology (e.g., for wildlife and for resiliency) as well as aesthetics and economic value. During this first year of funding the project has advanced considerably with respect to Goal 1 (outlined below). Goal 2 follows directly from Goal 1; Goal 2 be will be initiated once all bark communities are sequenced and processed bioinformatically. In addition, PI Garnas submitted a funding pre-proposal to NSF in support of Goals 3 and 4 above, which fall outside of the current McIntire-Stennis project. This pre-proposal received two "Very Good" and one "Good" review recommendation but was not invited for full proposal submission in 2018. A revised proposal will be submitted to NSF and/or USDA in 2019. With respect to Goal 1, key milestones include the following: Hired a postdoc to take responsibility for extensive field sampling and processing of samples and data as well as development and refinement (together with PI Garnas) of genetic and bioinformatic methods. Collected and processed over 400 bark plugs from eight states, as follows:ME: 95, MI: 31; NC: 62; NH: 5 NY: 131; PA: 62; WI: 42; WV: 67.These samples were collected along transects from trees with differing levels of infection and scale insect cover is a systematic and repeatable way. Site level data were also collected (i.e., beech basal area, species composition, slope, aspect, etc.) in support of Goal 2. Sequenced 12 pilot bark samples an Illumina HiSeq high throughput parallel sequencer using primers to barcode (identify and distinguish) key fungi know to be part of the beech bark disease system as well as many others that may be associated with disease and/or tree decline with varying specificity. We also developed a bioinformatic workflow (computational pipeline) for rapid and efficient analysis of abundant sequence data. This represents an important proof of concept and we were able to recover Neonectria and other fungal pathogens from infected beech tissue in a culture-free approach. Opportunistically collected samples and associated bark plugs from Neonectria-infected bark plugs across the range of the disease. Isolated and purified single-spore cultures from 104 bark plug samples for deeper genomic sequencing and development of a landscape genetic signature of both Neonectria pathogens for related work.
Publications
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2018
Citation:
Morrison EW, Heath J, Garnas, JR. 2018. Population genomics and community ecology of beech bark disease complex. MassMyco Bi-annual Meeting. Harvard University, MA.
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