Progress 03/01/15 to 02/28/18
Outputs
Target Audience:For this project, professional agroecology researchers are the primary audience. Efforts to reach the target audience this year included presentations at the Ecological Society of America Annual Meeting, one published paper, and one submitted manuscript currently under review. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Training activities during the lifetime of this project included involving 3 graduate students (2 Ph.D., 1 masters) and 6 undergraduate students in research. One masters student based her entire thesis on understanding belowground ecosystem services associated with different switchgrass varieties. One Ph.D. student started work evaluating whether AMF directly alter switchgrass cell wall composition (i.e., lignin), and will use data from this project in his dissertation. Another Ph.D. student worked to characterize the soil nematode communities associated with bienergy crops, and had this research published last year. Undergraduate students have aided with evaluating AMF and nematode abundance associated with switchgrass and miscanthus, giving them valuable experience as a research scientists. All students worked closely with the lead investigator to develop and perform research. Professional development activities includedattendance and research presentations at three Ecological Society of America Annual Meetings, the LTER Network All-Scientists Meeting, and a Great Lakes Bioenergy Research Center retreat. How have the results been disseminated to communities of interest?Results from this study have been disseminated to agroecology researchers at academic research conferences, in one paper published inGCB Bioenergy, and another manuscript in review at Biomass and Bioenergy. Two other journal articles are in preparation for submission later this year. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Impact: In response to the 2007 U.S. Energy Independence and Security Act which mandates production of 16 billion gallons of cellulosic ethanol by 2022, many farmers are considering growing warm season perennial grasses such as switchgrass (Panicum virgatum) and miscanthus (Miscanthus × giganteus) for cellulose feedstock, especially on marginal lands. These perennial grasslands can support greater biodiversity and provide more ecosystem services than annual crops. However, management considerations, such as what crop to plant and levels of fertilizer inputs, may alter ecosystem services provided by these grasslands, especially those influenced by belowground organisms, such as beneficial soil fungi. From 2015-2018, our research team (including 10 students) evaluated the effects of crop type, fertilization, and drought on crop yield, quality, and belowground ecosystem servicesin ongoing experiments associated with the Great Lakes Biofuels Research Center (GLBRC) and Long Term Ecological Research (LTER) project at the Kellogg Biological Station (KBS) in Michigan, USA. Overall, our results show that switchgrass increases soil ecosystem services compared to miscanthus, though switchgrass varieties do not differ much in their associations with soil organisms. Fertilization did not strongly influence plant associations with soil organisms or soil ecosystem services, and so low levels of fertilizer should benefit crops while avoiding any negative effects on soil organisms. Our experimental drought altered switchgrass associations with soil organisms and change plant tissue quality, but not quantity.Farmers interested in maximizing soil health associated with biofuel crops may want to choose native perennial grasses such as switchgrass, over non-native miscanthus; while farmers interested in maximizing biofuel quality should consider how biotic associations, especially during droughts, can affect plant growth. In this seed grant, we address three specific objectives in support of our main goal: 1) Do biofuel crops differ in their associations with AMF? From 2015-2018, we collected data on AMF root colonization and extra-radical hyphal growth associated with miscanthus and switchgrass growing as part of two ongoing experiments associated with the Great Lakes Biofuels Research Center (GLBRC) at the Kellogg Biological Station (KBS) in Michigan. Our results show that AMF activity was doubled in switchgrass compared to miscanthus. In comparing 12 different cultivars of switchgrass, we found no differences inAMF root colonization, extraradical hyphal growth, or associated AMF diversity. However, AMF root colonization was 6% higher in lowland compared to upland ecotypes. The key outcome is a change in knowledge of the belowground ecosystem services associated with soil AMF communities across different perennial biofuel crops. 2) Does fertilizer addition alter AMF diversity and composition in biofuel crops? From 2015-2018 we collected data from two long-term experiments examining effects of fertilizer on switchgrass and miscanthus.Our data showed that nitrogen fertilization had minor negative effects on AMF diversity associated with these perennial biofuel crops. The key outcome is a change in knowledge of how fertilizer management can influence belowground ecosystem services associated with soil AMF communitiesacross different perennial biofuel crops. 3) How does AMF diversity relate to ecosystem services in biofuel production systems? A precipitation manipulation experiment in 2015-16 quantified AMF associations with switchgrass under drought conditions. AMF root colonization and switchgrass lignin content decreased under rain shelters, while plant-parasitic nematode abundance increased, suggesting that biotic interactions with soil organisms may contribute to variation in biomass quality, possibly by triggering plant defense mechanisms. The key outcome is a change in knowledge of how AMF can improve ecosystem services associated with different perennial biofuel crops.
Publications
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2017
Citation:
Emery, S.M., M. L. Reid, L. Bell-Dereske, and K.L. Gross. 2017. Soil mycorrhizal and nematode activity and diversity vary in response to bioenergy crop identity and management. Ecological Society of America Annual Meeting, Portland OR. (contributed talk).
- Type:
Journal Articles
Status:
Published
Year Published:
2017
Citation:
Emery, S.M., M. Reid, L. Bell-Dereske, K.L. Gross. 2017. Soil mycorrhizal and nematode diversity vary in response to bioenergy crop identity and management. GCB Bioenergy; doi:10.1111/gcbb.12460
- Type:
Journal Articles
Status:
Under Review
Year Published:
2018
Citation:
Emery, S.M., E.R. Kinnetz, L. Bell-Dereske, K.A. Stahlheber, K.L. Gross, D. Pennington. In review. Low variation in arbuscular mycorrhizal fungal associations and effects on biomass among switchgrass cultivars. Biomass and Bioenergy.
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Progress 03/01/16 to 02/28/17
Outputs
Target Audience:For this project, professional agroecology researchers are the primary audience. Efforts to reach the target audience this year included presentations at the Ecological Society of America Annual Meeting,the Great Lakes Bioenergy Research Center Annual Sustainability Retreat, and the Kentucky Academy of Science. Changes/Problems:In 2016, we resolved issues with AMF DNA extraction and sequencing and will spend 2017 analyzing sequence data. The no-cost extension has also allowed us to add a new short-term field experiment in 2017to more explicitly examine mechanisms by which AMF affect ecosystem services associated with switchgrass grown for biofuel production. No further problems are anticipated. What opportunities for training and professional development has the project provided?Training activities during the secondyear of this project included involving 2 graduate students (1 Ph.D., 1 masters) and 5 undergraduate students in research. One masters studentbased her entire thesis on understanding belowground ecosystem services associated with different switchgrass varieties. One PhD student started work evaluating whether AMF directly alter switchgrass cell wall composition (i.e., lignin), and will use data from this project to inform future research directions. Undergraduate students have aided with evaluating AMF and nematode abundance associated with switchgrass and miscanthus, giving them valuable experience as a research scientists. All students worked closely with the lead investigator to develop and perform research.Professional development activities included Emery's attendance at the Ecological Society of America Annual Meeting. How have the results been disseminated to communities of interest?Results from the first two years of this study have been disseminated to agroecology researchers at academic research conferences, and are also in one manuscript under review at GCB Bioenergy. What do you plan to do during the next reporting period to accomplish the goals?Below we outline plans for our third year of this grant relevant to our three stated objectives. 1) Do biofuel crops differ in their associations with AMF? We were successful in perfecting DNA extractions and genetic sequencing of AMF in soils collected from experiments in 2015-16, after involving a new collaborator at Michigan State University, In 2017, we will finish analyzing sequence data, finish processing soil samples, and write manuscripts. 2) Does fertilizer addition alter AMF diversity and composition in biofuel crops? We will finish analyses of of AMF sequence data in soils collected from fertilization experiments and prepare manuscripts. 3) How does AMF diversity relate to ecosystem services in biofuel production systems? With an approved one-yearno-cost extension, we have initiateda short termexperiment manipulating AMF with the use of fungicidesin switchgrass fields at KBS. We will measure switchgrass growth and tissue quality in response to reduced AMF diversity in the field to better understand the mechanisist association between AMF and ecosystem services in biofuel production systems.The field experiment will run through October, and soil and plant samples will be processed over the winter.
Impacts
What was accomplished under these goals?
Impact: In response to the 2007 U.S. Energy Independence and Security Act which mandates production of 16 billion gallons of cellulosic ethanol by 2022, many farmers are considering growing warm season perennial grasses such as switchgrass (Panicum virgatum) and miscanthus (Miscanthus× giganteus) for cellulose feedstock, especially on marginal lands. These perennial grasslands can support greater biodiversity and provide more ecosystem services than annual crops. However, management considerations, such as what crop to plant and levels of fertilizer inputs, may alter ecosystem services provided by these grasslands, especially those influenced by belowground organisms. In 2016, our research team (including 5 students) evaluated the effects of switchgrass variety, fertilization, and precipitation on crop quantity, quality, and belowground ecosystem services in ongoing experiments associated with the Great Lakes Biofuels Research Center (GLBRC) and Long Term Ecological Research (LTER) project at the Kellogg Biological Station (KBS) in Michigan, USA. Biomass quantity was not consistently affected by switchgrass variety, fertilizer, or precipitation. For example, the Southlow variety of switchgrass, when fertilized, had higher yields compared to other treatments but drier soils canceled this effect. Biomass quality, measured as lignin content, was consistently reduced in low soil moisture conditions. AMF root colonization also decreased in dry soils, suggesting that this biotic interaction may contribute to variation in biomass quality, possibly by triggering plant defense mechanisms. Farmers interested in maximizing biofuel quantity and quality should consider how biotic and abiotic soil conditions can affect plant growth. In this seed grant, we address three specific objectives: 1) Do biofuel crops differ in their associations with AMF? To address this objective in 2016, we finished processing data on AMF root colonization and extra-radical hyphal growth associated with miscanthus and switchgrass growing as part of ongoing experiments associated with the Great Lakes Biofuels Research Center (GLBRC) at the Kellogg Biological Station (KBS) in Michigan. Our results show that AMF activity was doubled in switchgrass compared to miscanthus. Lab analyses continued for soils collected from an experiment comparing AMF associated with 12 varieties of switchgrass. The key outcome is a change in knowledge of the belowground ecosystem services associated with different perennial biofuel crops. 2) Does fertilizer addition alter AMF diversity and composition in biofuel crops? Data from experiments in 2016showed that nitrogen fertilization had minor negative effects on AMF diversity associated with these perennial biofuel crops. The key outcome is a change in knowledge of how fertilizer management can influence belowground ecosystem services associated with different perennial biofuel crops. 3) How does AMF diversity relate to ecosystem services in biofuel production systems? A rain-fall manipulation experiment in 2015-16 quantified AMF associations with switchgrass under drought conditions. AMF root colonization and switchgrass lignin content decreased under rain shelters, while plant-parasitic nematode abundance increased, suggesting that biotic interactions with soil organisms may contribute to variation in biomass quality, possibly by triggering plant defense mechanisms. Genetic analyses of diversity of AMF in roots and soils in this experiment are ongoing. The key outcome is a change in knowledge of how AMF can improve ecosystem services associated with different perennial biofuel crops.
Publications
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2016
Citation:
Emery, S.M., K.A. Stahlheber, K. L. Gross. 2016. Contrasting responses of two switchgrass varieties to fertilizer and reduced precipitation. Ecological Society of America Annual Meeting, Ft. Lauderdale, FL
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2016
Citation:
Kinnetz, E. and S.M. Emery. 2016. Intraspecific Differences in Panicum virgatum Association with Arbuscular Mycorrhizal Fungi. Kentucky Academy of Science Annual Meeting; Louisville KY
- Type:
Journal Articles
Status:
Under Review
Year Published:
2016
Citation:
Emery, S.M., M. Reid*, L. Bell-Dereske, K.L. Gross. Accepted pending revisions. Soil mycorrhizal and nematode diversity vary in response to bioenergy crop identity and management. GCB Bioenergy.
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Progress 03/01/15 to 02/29/16
Outputs
Target Audience:For this project, professional agroecology researchers are the primary audience. Efforts to reach the target audience this year included presentations at theEcological Society of America Annual Meeting, the Long Term Ecological Research Network All ScientistsMeeting (Biannual),and the Great Lakes Bioenergy Research Center Annual Sustainability Retreat. Changes/Problems:We are currently evaluating new techniques for characterizing AMF genetic diversity as previously proposed techniques (i.e., Illumina sequencing)are not currently recommended. We have started DNA extractions from roots and soils and will be working with collaborators to determine best methods for genetic sequencing of fungal communities. This may slow our progress in disseminating results via research manuscriptsa bit. The graduate student working as an RA on this project would benefit from a full year of support during the 2016-17 academic yearand I anticipate requesting a no-cost extension through July 2017 to accomodate academicschedules. What opportunities for training and professional development has the project provided?Training activities during the first year of this project included involving 3 graduate students (1 Ph.D., 2 masters) and 1undergraduate student in research. One masters student is basing her entire thesis on understanding belowground ecosystem services associated with different switchgrass varieties. One undergraduate student conducted independent summer research in 2015 focused on evaluating AMF abundance associated with switchgrass and miscanthus, giving her valuable experience as a research scientist. All students worked closely with the lead investigator to develop and perform research. Professional development activities included Emery's attendance at a retreat sponsored by the Great Leakes Bioenergy Research Center. How have the results been disseminated to communities of interest?Preliminary results from the first year of this study have been disseminated to agroecology researchers at academic research conferences. What do you plan to do during the next reporting period to accomplish the goals?Below we outline plans for our second year of this grant relevant toour three stated objectives. 1) Do biofuel crops differ in their associations with AMF? We will focus efforts in 2016 on perfecting DNA extractions and genetic sequencing of AMF in roots and soils collected from experiments in 2015. This may involve some new collaborations with microbial ecologists at Michigan State University, as techniques have evolved since our original proposal was submitted and are not currently recommended for characterization of fungal diversity. We will also continue ongoing analyses of AMF spore abundance and diversity from 2015 soil samples. 2) Does fertilizer addition alter AMF diversity and composition in biofuel crops? We will focus efforts in 2016 on perfecting DNA extractions and genetic sequencing of AMF in roots and soils collected from fertilization experiments in 2015. We will also continue ongoing lab analyses of AMF activity associated with a fertilization-gradient experiment using soils collected in 2015. 3) How does AMF diversity relate to ecosystem services in biofuel production systems? We will continue our rain-fall manipulation experiment for a second growing season (2016), quantifying the role that AMF play in switchgrass drought tolerance in fertilized and unfertilized systems. We will also conduct more detailed analyses on diversity and composition of plant-parasitic nematode communities associated with different biofuel crops.
Impacts
What was accomplished under these goals?
Impact: In response to the 2007 U.S. Energy Independence and Security Act which mandates production of 16 billion gallons of cellulosic ethanol by 2022, many farmers are considering growing warm season perennial grasses such as switchgrass (Panicum virgatum) and miscanthus (Miscanthus× giganteus) for cellulose feedstock, especially on marginal lands. These perennial grasslands can support greater biodiversity and provide more ecosystem services than annual crops. However, management considerations, such as what crop to plant and levels of fertilizer inputs, may alter ecosystem services provided by these grasslands, especially those influenced by belowground organisms. In 2015, our research team (including 4 students) evaluated the effects of crop identity and fertilization on arbuscular mycorrhizal fungal (AMF) activity in ongoing experiments associated with the Great Lakes Biofuels Research Center (GLBRC) at the Kellogg Biological Station (KBS) in Michigan, USA. Our preliminary results show that AMF activity was doubled in switchgrass compared to miscanthus. Fertilization tripled plant-parasitic nematode abundance in both crops, and tended to increase AMF activity, possibly due to increased root biomass. These first-year results indicate that switchgrass may enhance soil carbon storage compared to miscanthus by increasing AMF activity belowground. Farmers interested in maximizing soil health associated with biofuel crops may want to choose native perennial grasses such as switchgrass, over non-native miscanthus. In this seed grant, we proposed to address three specific objectives: 1) Do biofuel crops differ in their associations with AMF? To address this objective in 2015, we collected data on AMF root colonization and extra-radical hyphal growth associated with miscanthus and switchgrass growing as part of ongoing experiments associated with the Great Lakes Biofuels Research Center (GLBRC) at the Kellogg Biological Station (KBS) in Michigan. Our preliminary results show that AMF activity was doubled in switchgrass compared to miscanthus. Soils were also collected from an experiment comparing AMF associated with 12 varieties of switchgrass, with lab analyses ongoing. The key outcome is a change in knowledge of the belowground ecosystem services associated with different perennial biofuel crops. 2) Does fertilizer addition alter AMF diversity and composition in biofuel crops? Soils collected from experiments in 2015 showed that AMF have inconsistent responses to fertilizer, dependent on crop variety. AMF associated with the Cave-in-Rock variety of switchgrass were more active in fertilized soils, while those associated with the Southlow variety were more active in unfertilized soils. For miscanthus, fertilization tended to increase AMF activity. Genetic analyses of diversity of AMF in roots and soils are ongoing. The key outcome is a change in knowledge of how fertilizer management can influence belowground ecosystem services associated with different perennial biofuel crops. 3) How does AMF diversity relate to ecosystem services in biofuel production systems? We established a rain-fall manipulation experiment in 2015 to quantify AMF associations with switchgrass under drought conditions. In 2015, The Cave-in-Rock variety of switchgrass had higher AMF abundance and greater biomass production in dry compared to ambient conditions, whereas this pattern was reversed for the Southlow variety. Genetic analyses of diversity of AMF in roots and soils in this experiment are ongoing. Preliminary results show no significant relationship between AMF activity and plant-parasitic nematode abundance in either switchgrass or miscanthus in 2015. The key outcome is a change in knowledge of how AMF can improve ecosystem services associated with different perennial biofuel crops.
Publications
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2015
Citation:
Emery, S.M., A.N. Carey, L. Mueller, and C.B. Gottshall. 2015. Perennial biofuel crop identity and management alter abundance and activity of soil organisms. Ecological Society of America Annual Meeting, Baltimore, MD (contributed poster).
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2015
Citation:
Emery, S.M., A.N. Carey, L. Mueller, and C.B. Gottshall. 2015. Perennial biofuel crop identity and management alter abundance and activity of soil organisms. LTER Network All-Scientists Meeting, Estes Park, CO (poster).
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2016
Citation:
Emery, S.M., A.N. Carey, L. Mueller, and C.B. Gottshall. 2016. Perennial biofuel crop identity and management alter abundance and activity of soil organisms. GLBRC Sustainability Retreat; Hickory Corners, MI (poster).
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2016
Citation:
Stahlheber, K.A., S.M. Emery, and K.L. Gross. 2016. Inter- and intraspecific trait variation in perennial native grasses planted at Kellogg Biological Station. GLBRC Sustainability Retreat; Hickory Corners, MI (poster).
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