Progress 04/01/18 to 03/31/20
Outputs
Target Audience: My target audience during this portion of the reporting period has included the broader scientific community. I have presented findings and data from my proposed work to 3 different conference in the past year, two international and one in the USA. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Training Activities: Through the first year of the grant, I have had the pleasure of working with 4 undergraduate research assistants. Through this work, we have gained major traction towards to goals of the grant. In addition, training these individuals in the scientific process has allowed them to grow in their proficiency as well as provide them experience in research and academia. Professional Development: As I proposed in the grant, I organized a symposium of research seminars at a national conference where we discussed the research ideas proposed in this grant and other related scientific discoveries (many of which also funded through USDA NIFA). In addition to this, I was invited to give 5seminars during the award todissiminate findings of this work. How have the results been disseminated to communities of interest? Information and results relating to this work have been primarily disseminated through research talks and seminars given by myself. In the past year, I have given several of these to diverse audiences both nationally and internationally. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
1. The goal of this research is to better understand the ways in which predatory insects can affect prey ecology. When we typically think of predators, we immediately imagine the consumptive effect that they have - that is, direct removal of prey through consumption. However, prey are not defenseless and will initiate anti-predator behavioral and physiological responses upon detection of threat in order to avoid being eaten. These alterations in behavior and physiology can be energetically costly and can have impacts on the overall survival and performance of the insect prey even though they might avoid being eaten. This is considered the non-consumptive effect of predators. The main objective of this work is to identify how predation risk affects behavior and physiology of a major insect pest of agricultural crops and then to use this information to manipulate the distribution and success of this pest in agroecosystems through integrated pest management. 2. During the first year of this grant, I have worked conduct experiments to address the behavioral alterations as well as the physiological changes that occur in response to a common insect predator. When aphid prey are exposed to their ladybeetle predators, we found that they will reduce the number of offspring they produce over a short time period. However, over a longer time period, exposure to predators actually increases overall aphid numbers. In addition, physiological changes were also found: aphids will produce offspring that have wings after being exposed to predators. This suggests that aphids are able to detect the lady beetle predators and response by altering their offspring production and investing in dispersal in the following generation. Importantly, detection of predation risk occurred without physical contact with the predators. In the assays, aphid prey were separated from the predators by mesh which allowed for only chemical and visual cues of the predators to be detected. 3. These results suggest that, by manipulating the presence of predators near crop plants where pest insects reside, we might be able to change the behavior and pshyiology of insect pests in a way that alters their relationship with the host plant. Further, this work suggests that predator cues are enough to elicit behavioral and physiological responses that could affect the interaction between aphid pests and their host plants. Aphids reduce their offspring production at first, which is better for the plants. But, over time, aphids might actually be increasing their populations when in the presence of predator cues which could lead to a negative impact on plants. However, when aphids produce more offspring in the presence of predator cues, we also found that these offspring tend to be winged suggesting they would disperse from the host plant and seek out an alternative host. More work in a field setting will be needed to tease this apart. Objective 1: Assess how predation risk affects aphid behavior and reproduction 1. Experiments were conducted to assess how predation risk affects aphid behavior and reproduction in a series of experiments. First, we used a small arena (modified petri-dish) to examine the short-term impact of predator presence on aphid reproduction. Over 3 days we examined total nymphs produced by individual aphid females. Then, we examined these interactions in a larger arena for a longer period of time (14 days). In this case, we also were able to examine the number of winged dispersal morphs formed in offspring of mothers that received predator exposure. 2. We collected data on offspring produced and wing formation. We examined this in both winged and wingless adult females. 3. The presence of both predator cues from H. axyridis predators in a petri dish arena led to a 23% reduction in the overall number of nymphs produced by adult apterous M. persicae over 3 d compared to reproducing adult aphids in control petri dishes where predator cues were absent (Z = -4.08, p < 0.0001). However, when adult alate M. persicae were left to reproduce in the presence of predator cues there was no discernable effect on nymph production compared to predator-free controls (Z = -0.46, p = 0.65). The number of individuals that produced wings after 3 d in petri dishes differed between the predator cue treatment and the predator-free control, with a five-fold increase in alate production in the predator cue treatment (G = 8.73, p = 0.003). Overall, 3% of aphids in the control treatment were winged after 3 d whereas 15% of aphids formed wings in the treatment dishes that left aphids exposed to predator cues. In larger arenas over a longer time period, nymph production differed significantly among treatments (c2= 32.87, p < 0.0001, Figure 4). Pairwise comparisons of the different treatments show that the risk treatment yielded significantly more nymphsthan the control and lethal treatments (Z = 3.219, p = 0.0013; Z = 4.903, p < 0.0001, respectively) while lethal treatment had the fewest aphids after 14 d. Alate formation (n = 12) was significantly increased in the risk treatment compared to both the control and lethal treatment where no alates were found during the entire experiment (G = 16.636, p < 0.0001). 4. All data collected resulted in changed in knowledge - this work is currently being prepared for publication. Objective 2: Identify the mechanism by which aphids perceive predator risk 1.Two-arm olfactometer experiments were designed to determine the effects of ladybeetle volatile odor cues on the behavior of the prey insect, M. persicae.Here, the aim was to determine if chemical cues of the predator are responsible for behavioral changes in the prey. 2.We collected data on host choice of both winged and wingless adult aphids. 3.When presented with a choice between a predator-free odor source or an odor source that included H. axyridis predators, adult apterous M. persicae preferred the arm with predator-free control plants (c2= 5.12, p = 0.024). However, when the physical predators were removed from the odor source arena prior to bioassays, the adult apterous aphids no longer preferred predator-free control plants (c2= 3, p = 0.083). In contrast, alate M. persicaepreferred to move towards plants with predators present compared to the predator-free odor source (c2=7.53, p = 0.006), but only when the physical predators were in the odor source arena. When predators were removed from the odor source arena prior to bioassays, we observed equal preference between the olfactometer arms was observed (c2= 0.037, p = 0.847). 4. All data collected resulted in changed in knowledge - this work is currently being prepared for publication. Objective 3: (a.) Identify semiochemical blend of H. axyridis and (b.) examine for bioactivity 1. no experiments have been initiated, this is the next step of the work. 2. coming soon 3. coming soon 4. coming soon
Publications
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2019
Citation:
Sara Hermann and Doug Landis, "Risk Management: Consequences of predation risk on behavior, physiology and fitness". 2019. International Society for Chemical Ecology Annual Meeting, Atlanta, Georgia.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2019
Citation:
Sara Hermann, Carissa Blackledge, Nathan Haan, Andrew Myers and Douglas Landis. Predators of monarch butterfly eggs and neonates are more diverse than previously recognised. Scientific Reports.
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2019
Citation:
Sara Hermann and Doug Landis, "Harnessing anti-predator behavioral responses to manage insect pests". 2019. Entomological Society of America - North Central Branch Meeting, Cincinnati, Ohio.
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2019
Citation:
Hermann, Sara, L. 2019. "Impact of Predation Risk on the Behavior and Physiology of Insects in Agricultural Systems" Diss. Michigan State University, 2019.
|
Progress 04/01/18 to 01/08/20
Outputs
Target Audience: My target audience during this portion of the reporting period has included the broader scientific community. I have presented findings and data from my proposed work to 3 different conference in the past year, two international and one in the USA. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Training Activities: Through the first year of the grant, I have had the pleasure of working with 4 undergraduate research assistants. Through this work, we have gained major traction towards to goals of the grant. In addition, training these individuals in the scientific process has allowed them to grow in their proficiency as well as provide them experience in research and academia. Professional Development: As I proposed in the grant, I organized a symposium of research seminars at a national conference where we discussed the research ideas proposed in this grant and other related scientific discoveries (many of which also funded through USDA NIFA). In addition to this, I was invited to give 5seminars during the award todissiminate findings of this work. How have the results been disseminated to communities of interest? Information and results relating to this work have been primarily disseminated through research talks and seminars given by myself. In the past year, I have given several of these to diverse audiences both nationally and internationally. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
1. The goal of this research is to better understand the ways in which predatory insects can affect prey ecology. When we typically think of predators, we immediately imagine the consumptive effect that they have - that is, direct removal of prey through consumption. However, prey are not defenseless and will initiate anti-predator behavioral and physiological responses upon detection of threat in order to avoid being eaten. These alterations in behavior and physiology can be energetically costly and can have impacts on the overall survival and performance of the insect prey even though they might avoid being eaten. This is considered the non-consumptive effect of predators. The main objective of this work is to identify how predation risk affects behavior and physiology of a major insect pest of agricultural crops and then to use this information to manipulate the distribution and success of this pest in agroecosystems through integrated pest management. 2. During the first year of this grant, I have worked conduct experiments to address the behavioral alterations as well as the physiological changes that occur in response to a common insect predator. When aphid prey are exposed to their ladybeetle predators, we found that they will reduce the number of offspring they produce over a short time period. However, over a longer time period, exposure to predators actually increases overall aphid numbers. In addition, physiological changes were also found: aphids will produce offspring that have wings after being exposed to predators. This suggests that aphids are able to detect the lady beetle predators and response by altering their offspring production and investing in dispersal in the following generation. Importantly, detection of predation risk occurred without physical contact with the predators. In the assays, aphid prey were separated from the predators by mesh which allowed for only chemical and visual cues of the predators to be detected. 3. These results suggest that, by manipulating the presence of predators near crop plants where pest insects reside, we might be able to change the behavior and pshyiology of insect pests in a way that alters their relationship with the host plant. Further, this work suggests that predator cues are enough to elicit behavioral and physiological responses that could affect the interaction between aphid pests and their host plants. Aphids reduce their offspring production at first, which is better for the plants. But, over time, aphids might actually be increasing their populations when in the presence of predator cues which could lead to a negative impact on plants. However, when aphids produce more offspring in the presence of predator cues, we also found that these offspring tend to be winged suggesting they would disperse from the host plant and seek out an alternative host. More work in a field setting will be needed to tease this apart. Objective 1: Assess how predation risk affects aphid behavior and reproduction 1. Experiments were conducted to assess how predation risk affects aphid behavior and reproduction in a series of experiments. First, we used a small arena (modified petri-dish) to examine the short-term impact of predator presence on aphid reproduction. Over 3 days we examined total nymphs produced by individual aphid females. Then, we examined these interactions in a larger arena for a longer period of time (14 days). In this case, we also were able to examine the number of winged dispersal morphs formed in offspring of mothers that received predator exposure. 2. We collected data on offspring produced and wing formation. We examined this in both winged and wingless adult females. 3. The presence of both predator cues from H. axyridis predators in a petri dish arena led to a 23% reduction in the overall number of nymphs produced by adult apterous M. persicae over 3 d compared to reproducing adult aphids in control petri dishes where predator cues were absent (Z = -4.08, p < 0.0001). However, when adult alate M. persicae were left to reproduce in the presence of predator cues there was no discernable effect on nymph production compared to predator-free controls (Z = -0.46, p = 0.65). The number of individuals that produced wings after 3 d in petri dishes differed between the predator cue treatment and the predator-free control, with a five-fold increase in alate production in the predator cue treatment (G = 8.73, p = 0.003). Overall, 3% of aphids in the control treatment were winged after 3 d whereas 15% of aphids formed wings in the treatment dishes that left aphids exposed to predator cues. In larger arenas over a longer time period, nymph production differed significantly among treatments (c2= 32.87, p < 0.0001, Figure 4). Pairwise comparisons of the different treatments show that the risk treatment yielded significantly more nymphsthan the control and lethal treatments (Z = 3.219, p = 0.0013; Z = 4.903, p < 0.0001, respectively) while lethal treatment had the fewest aphids after 14 d. Alate formation (n = 12) was significantly increased in the risk treatment compared to both the control and lethal treatment where no alates were found during the entire experiment (G = 16.636, p < 0.0001). 4. All data collected resulted in changed in knowledge - this work is currently being prepared for publication. Objective 2: Identify the mechanism by which aphids perceive predator risk 1.Two-arm olfactometer experiments were designed to determine the effects of ladybeetle volatile odor cues on the behavior of the prey insect, M. persicae.Here, the aim was to determine if chemical cues of the predator are responsible for behavioral changes in the prey. 2.We collected data on host choice of both winged and wingless adult aphids. 3.When presented with a choice between a predator-free odor source or an odor source that included H. axyridis predators, adult apterous M. persicae preferred the arm with predator-free control plants (c2= 5.12, p = 0.024). However, when the physical predators were removed from the odor source arena prior to bioassays, the adult apterous aphids no longer preferred predator-free control plants (c2= 3, p = 0.083). In contrast, alate M. persicaepreferred to move towards plants with predators present compared to the predator-free odor source (c2=7.53, p = 0.006), but only when the physical predators were in the odor source arena. When predators were removed from the odor source arena prior to bioassays, we observed equal preference between the olfactometer arms was observed (c2= 0.037, p = 0.847). 4. All data collected resulted in changed in knowledge - this work is currently being prepared for publication. Objective 3: (a.) Identify semiochemical blend of H. axyridis and (b.) examine for bioactivity 1. no experiments have been initiated, this is the next step of the work. 2. coming soon 3. coming soon 4. coming soon
Publications
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2019
Citation:
Sara Hermann and Doug Landis, "Risk Management: Consequences of predation risk on behavior, physiology and fitness". 2019. International Society for Chemical Ecology Annual Meeting, Atlanta, Georgia.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2019
Citation:
Sara Hermann, Carissa Blackledge, Nathan Haan, Andrew Myers and Douglas Landis. Predators of monarch butterfly eggs and neonates are more diverse than previously recognised. Scientific Reports.
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2019
Citation:
Sara Hermann and Doug Landis, "Harnessing anti-predator behavioral responses to manage insect pests". 2019. Entomological Society of America - North Central Branch Meeting, Cincinnati, Ohio.
- Type:
Theses/Dissertations
Status:
Published
Year Published:
2019
Citation:
Hermann, Sara, L. 2019. "Impact of Predation Risk on the Behavior and Physiology of Insects in Agricultural Systems" Diss. Michigan State University, 2019.
|
Progress 04/01/18 to 03/31/19
Outputs
Target Audience: My target audience during this portion of the reporting period hasincluded the broader scientific community.I have presented findings and data from my proposed work to 3 different conference in the past year, two international and one in the USA. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Training Activities: Through the first year of the grant, I have had the pleasure of working with 4 undergraduate research assistants. Through this work, we have gained major traction towards to goals of the grant. In addition, training these individuals in the scientific process has allowed them to grow in their proficiency as well as provide them experience in research and academia. Professional Development: As I proposed in the grant, I organized a symposium of research seminars at a national conference where we discussed the research ideas proposed in this grant and other related scientific discoveries (many of which also funded through USDA NIFA). In addition to this, I was invited to give 3 seminars at conferences in the past year to dissiminate findings of this work. How have the results been disseminated to communities of interest?Information and results relating to this work have been primarily disseminated through research talks and seminars given by myself. In the past year, I have given several of these to diverse audiences both nationally and internationally. What do you plan to do during the next reporting period to accomplish the goals?During the next reporting period, I plan to complete the work for objective 3. I will also prepare and submit the results from the first two objectives to scientific journals for publication. Lastly, I will continue to give talks relating to my results at conferences over the next year (at least 2 conferences).
Impacts
What was accomplished under these goals?
The goal of this research is to better understand the ways in which predatory insects can affect prey ecology. When we typically think of predators, we immediately imagine the consumptive effect that they have - that is, direct removal of prey through consumption. However, prey are not defenseless and will initiate anti-predator behavioral and physiological responses upon detection of threat in order to avoid being eaten. These alterations in behavior and physiology can be energetically costly and can have impacts on the overall survival and performance of the insect prey even though they might avoid being eaten. This is considered the non-consumptive effect of predators. The main objective of this work is to identify how predation risk affects behavior and physiology of a major insect pest of agricultural crops and then to use this information to manipulate the distribution and success of this pest in agroecosystems through integrated pest management. During the first year of this grant, I have worked conduct experiments to address the behavioral alterations as well as the physiological changes that occur in response to a common insect predator. When aphid prey are exposed to their ladybeetle predators, we found that they will reduce the number of offspring they produce over a short time period. However, over a longer time period, exposure to predators actually increases overall aphid numbers. In addition, physiological changes were also found: aphids will produce offspring that have wings after being exposed to predators. This suggests that aphids are able to detect the lady beetle predators and response by altering their offspring production and investing in dispersal in the following generation. Importantly, detection of predation risk occurred without physical contact with the predators. In the assays, aphid prey were separated from the predators by mesh which allowed for only chemical and visual cues of the predators to be detected. These results suggest that, by manipulating the presence of predators near crop plants where pest insects reside, we might be able to change the behavior and pshyiology of insect pests in a way that alters their relationship with the host plant. Further,this work suggests that predator cues are enough to elicit behavioral and physiological responses that could affect the interaction between aphid pests and their host plants. Aphids reduce their offspring production at first, which is better for the plants. But, over time, aphids might actually be increasing their populations when in the presence of predator cues which could lead to a negative impact on plants. However, when aphids produce more offspring in the presence of predator cues, we also found that these offspring tend to be winged suggesting they would disperse from the host plant and seek out an alternative host. More work in a field setting will be needed to tease this apart. Objective 1: Assess how predation risk affects aphid behavior and reproduction 1. Experiments were conducted to assess how predation risk affects aphid behavior and reproduction in a series of experiments. First, we used a small arena (modified petri-dish) to examine the short-term impact of predator presence on aphid reproduction. Over 3 days we examined total nymphs produced by individual aphid females. Then, we examined these interactions in a larger arena for a longer period of time (14 days). In this case, we also were able to examine the number of winged dispersal morphs formed in offspring of mothers that received predator exposure. 2. We collected data on offspring produced and wing formation. We examined this in both winged and wingless adult females. 3. The presence of both predator cues fromH. axyridispredators in a petri dish arena led to a 23% reduction in the overall number of nymphs produced by adult apterousM. persicaeover 3 d compared to reproducing adult aphids in control petri dishes where predator cues were absent (Z = -4.08, p < 0.0001).However, when adult alateM. persicaewere left to reproduce in the presence of predator cues there was no discernable effect on nymph production compared to predator-free controls (Z = -0.46, p = 0.65). The number of individuals that produced wings after 3 d in petri dishes differed between the predator cue treatment and the predator-free control, with a five-fold increase in alate production in the predator cue treatment (G = 8.73, p = 0.003). Overall, 3% of aphids in the control treatment were winged after 3 d whereas 15% of aphids formed wings in the treatment dishes that left aphids exposed to predator cues. In larger arenas over a longer time period, nymph production differed significantly among treatments (c2= 32.87, p < 0.0001, Figure 4). Pairwise comparisons of the different treatments show that the risk treatment yielded significantly more nymphs than the control and lethal treatments (Z = 3.219, p = 0.0013; Z = 4.903, p < 0.0001, respectively) while lethal treatment had the fewest aphids after 14 d. Alate formation (n = 12) was significantly increased in the risk treatment compared to both the control and lethal treatment where no alates were found during the entire experiment (G = 16.636, p < 0.0001). 4. All data collected resulted in changed in knowledge - this work is currently being prepared for publication. Objective 2: Identify the mechanism by which aphids perceive predator risk 1.Two-arm olfactometer experiments were designed to determine the effects of ladybeetle volatile odor cues on the behavior of the prey insect,M. persicae.Here, the aim was to determine if chemical cues of the predator are responsible for behavioral changes in the prey. 2.We collected data on host choice of both winged and wingless adult aphids. 3.When presented with a choice between a predator-free odor source or an odor source that includedH. axyridispredators, adult apterousM. persicaepreferred the arm with predator-free control plants (c2= 5.12, p = 0.024). However, when the physical predators were removed from the odor source arena prior to bioassays, the adult apterous aphids no longer preferred predator-free control plants (c2= 3, p = 0.083). In contrast, alateM. persicaepreferred to move towards plants with predators present compared to the predator-free odor source (c2=7.53, p = 0.006), but only when the physical predators were in the odor source arena. When predators were removed from the odor source arena prior to bioassays, we observed equal preference between the olfactometer arms was observed (c2= 0.037, p = 0.847). 4. All data collected resulted in changed in knowledge - this work is currently being prepared for publication. Objective 3: (a.) Identify semiochemical blend of H. axyridis and (b.) examine for bioactivity 1. no experiments have been initiated, this is the next step of the work. 2. coming soon 3. coming soon 4. coming soon
Publications
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2018
Citation:
Sara Hermann and Doug Landis, "Flying into the Face of Fear: Predator cues influence aphid development and behavior". 2018. International Society for Chemical Ecology Annual Meeting, Budapest, Hungary.
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2018
Citation:
Sara Hermann and Doug Landis, "Effects of Predation Risk on Insect Behavior and Physiology". 2018. Entomological Society of America Annual Meeting, Vancouver, Canada.
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2019
Citation:
Sara Hermann and Doug Landis, "Harnessing anti-predator behavioral responses to manage insect pests". 2019. Entomological Society of America - North Central Branch Meeting, Cincinnati, Ohio.
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