Annual/Termination Reports:

[09/07/2006] [11/15/2007] [09/24/2008] [09/30/2009] [09/30/2010]

Report Information

Participants

Attached

Brief Summary of Minutes

Attached. Note summary of "action items" provided at end of document.

Accomplishments

The overarching objective of the NC1026 project and its multi-state group of collaborators is to determine the importance of representing demographic realism within weed decision support systems (DSS) and to facilitate incorporating the information that can best help to improve weed management decision-making. Over the course of the last year, the most widely used DSS, WeedSoft, was overhauled in order to determine the importance weed escapes on the decisions recommended by the software. Our examination revealed that some fundamental processes, such as a lack of synchrony in weed emergence, were not and could not be represented within the current framework. We therefore initiated a plan to create a simplified version of WeedSoft and compare its decision-making performance with a set of more demographically realistic alternatives in order to assess the value of changing how it represents weed-crop competition and the response of weed population to various management interventions.<br /> <br /> The group also accomplished a great deal experimentally. Six collaborators conducted the demography protocol (Object 1a) and several modifications were agreed upon moving into the next year. The demography information provided by the regional experiment will provide a means for assessing the importance of modifying the structure of a DSS like WeedSoft so as to incorporate a more realistic representation of the impact of weeds and how they respond to management. Initial reports from those conducting the soil training experiments (Objective 1b) were also very interesting and could strongly influence our assessment of the value of adding additional biological realism into weed decision support tools. If the weed decision support tools are to evolve beyond herbicide selection for different crop-weed scenarios, it will be through efforts like this regional project.<br />

Publications

Davis, A. S. , J. Cardina, F. Forcella, G. A. Johnson, G. Kegode, J. L. Lindquist, E. C. Luschei, K. A. Renner, C. L. Sprague, and M. M. Williams II. 2005. Environmental factors affecting seed persistence of 13 annual weeds. Weed Science 53: 860-868.

Impact Statements

1. Improved realism in weed decision support systems
2. Understanding the cost of weed escapes
3. Maximize value of weed control resources

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Report Information

Participants

Sharon Clay (SD), Don Wyse (MN), James Parochetti (CSREES), John Cardina (OH), Frank Forcella (MN, USDA-ARS), John Lindquist (NE), Christy Sprague (MI), Doug Buhler (Administrative Advisor, MI), Adam Davis (IL, USDA-ARS), Bruce Maxwell (MT), Anita Dille (KS), Analiza Haydee Ramirez (KS), David Archer (MN, USDA-ARS), Joel Felix (OR)

Brief Summary of Minutes

Accomplishments

The overarching goal of the NC1026 project and its multi-state group of collaborators is to determine the importance of representing demographic realism within weed decision support systems (DSS) and to facilitate incorporating the information that can best help to improve weed management decision-making. Over the course of the last two years, the most widely used weed management DSS, WeedSOFT, was overhauled to determine the importance of how weeds that survive management treatment affect decisions recommended by the software. Our examination revealed that some fundamental processes, such as a lack of synchrony in weed emergence, were not and could not be represented within the current framework. Therefore, we initiated a plan to create a simplified version of WeedSOFT and compare its decision-making performance with a set of more demographically realistic alternatives in order to assess the value of changing how it represents weed-crop competition and the response of weed populations to various management interventions. The WeedSOFT program itself is currently under revision for distribution via the worldwide web. <br /> <br /> <br /> The group also accomplished a great deal experimentally. Six collaborators have conducted the demography experiment (Objective 1a) over two growing seasons. The demography information provided by the regional experiment will provide a means for assessing the importance of modifying the structure of a DSS like WeedSOFT so as to incorporate a more realistic representation of the impact of weeds and how they respond to management. Initial reports from those conducting the soil training experiments (Objective 1b) were also very interesting and could strongly influence our assessment of the value of adding additional biological realism into weed decision support tools. If the weed decision support tools are to evolve beyond herbicide selection for different crop-weed scenarios, it will be through efforts like this regional project. <br />

Publications

Terra, B. R. M., A. R. Martin and J. L. Lindquist. 2007. Corn-velvetleaf (Abutilon theophrasti) interference is affected by sublethal doses of postemergence herbicides. Weed Science 55:491-496.<br /> <br /> <br /> Hock, S. M., S. Z. Knezevic, A. R. Martin and J. L. Lindquist. 2006. Performance of WeedSOFT for predicting soybean yield loss. Weed Technology 20:478-484.<br />

Impact Statements

1. Members of NC1026 developed the computer-based decision support system, WeedSOFT, which is distributed to more than 500 users in 9 states over the last two years.
2. NC202 (prior to NC1026) research showed that research conducted at multiple locations throughout the region over multiple years provide better information for decision making than single location experiments.
3. NC1026 research showed that weed germination and emergence is environment specific and understanding the mechanisms controlling these factors are required to effectively predict where and when weeds problems will occur.
4. Members of NC1026 showed that weeds surviving sublethal doses of pre- and post-emergent herbicides often do not effect crop yield and produce substantially fewer seeds than untreated weeds.
5. NC1026 research has improved and strengthened the weed management recommendations of WeedSOFT and other decision-support software.
6. Members of NC1026 are now working to include this research-based information into educational modules for a web-delivered version of WeedSOFT.
7. NC1026 research created greater insight into how management strategies and environmental factors influence the degradation and longevity of weed seed banks.

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Report Information

Participants

Sharon Clay (SD); John Cardina (OH); John Lindquist (NE); Christy Sprague (MI); Doug Buhler (Administrative Advisor, MI); Adam Davis (IL, USDA-ARS); Anita Dille (KS); Analiza Haydee Ramirez (KS); Joel Felix (OR); and Jack Dekker (IA)

Brief Summary of Minutes

The annual meeting was held at the Lied Conference Center, Nebraska City, NE on July 29-30, 2008. The meeting started with a reminder from the research group advisor that the current NC1026 project will expire in September 2010. One option is to rewrite the proposal for renewal; in which case the revised proposal will need to be in the system by December 2009. The other option is to prepare a new proposal to address other issues that will hopefully build onto previous research topics. After a long discussion, it was agreed that the group members will brainstorm and meet again during the 2008 North Central Weeds Science Society (NCWSS) and or the Weed Science Society of America (WSSA) meetings to decide on the next move. Researchers presented reports on the ongoing research objectives. It was suggested that analyzing the demography data (Objective 1a) using Julian weeks (instead of thermal time) may help to tease out weed emergence opportunity spaces at each test site. It was agreed that different data analysis considerations will be looked at by those leading preparation of manuscripts for publication. It was further noted that participation in the NC1026 research project needs to be improved by recruiting new members. There was a consensus that a letter be sent out to particular individuals (and current members who did not attend the meeting) with an invitation to attend the brain storming meeting at the NCWSS and WSSA. The next group meeting will be held at Kellogg Biological Station, Hickory Corners, MI. from July 27-29, 2009.

Accomplishments

The overarching goal of the NC1026 project and its multi-state group of collaborators is to determine the importance of representing demographic realism within weed decision support systems (DSS) and to facilitate incorporating the information that can best help to improve weed management decision-making. Over the course of the last two years, the most widely used weed management DSS, WeedSOFT, was overhauled to determine the importance of how weeds that survive management treatment affect decisions recommended by the software. Our examination revealed that some fundamental processes, such as a lack of synchrony in weed emergence, were not and could not be represented within the current framework. Therefore, we initiated a plan to create a simplified version of WeedSOFT and compare its decision-making performance with a set of more demographically realistic alternatives in order to assess the value of changing how it represents weed-crop competition and the response of weed populations to various management interventions. The WeedSOFT program itself is currently under revision for distribution via the worldwide web. A grant from the NC-IPM was received in 2008 to support efforts to rebuild WeedSOFT as an Internet-based integrated weed management decision tool that will be available free of charge to the users.<br /> <br /> The group also accomplished a great deal experimentally. Five collaborators have conducted the demography experiment (Objective 1a) over two growing seasons. The demography information provided by the regional experiment will provide a means for assessing the importance of modifying the structure of a DSS like WeedSOFT so as to incorporate a more realistic representation of the impact of weeds and how they respond to management. Progress reports from those conducting the soil training experiments (Objective 1b) were also very interesting and could strongly influence our assessment of the value of adding additional biological realism into weed decision support tools. If the weed decision support tools are to evolve beyond herbicide selection for different crop-weed scenarios, it will be through efforts like this regional project. <br />

Publications

Terra, B. R. M., A. R. Martin and J. L. Lindquist. 2007. Corn-velvetleaf (Abutilon theophrasti) interference is affected by sublethal doses of postemergence herbicides. Weed Science 55:491-496.

Impact Statements

1. " Members of NC1026 continued to develop the computer-based decision support system, WeedSOFT, which is used by more than 500 users in 9 states over the last two years. Efforts are under way to develop a web-based version of WeedSOFT to enable a wider use of this valuable tool. Funding from NC-IPM has been extended to WeedSOFT programmers so as to expedite the process.
2. " Previous research showed that multi-location studies throughout the region over multiple years provide better information for decision making than single location experiments.
3. " NC1026 research showed that weed germination and emergence is environment specific and understanding the mechanisms controlling these factors are required to effectively predict where and when weeds problems will occur.
4. " Members of NC1026 showed that weeds surviving sublethal doses of pre- and post-emergent herbicides often do not effect crop yield and produce substantially fewer seeds than untreated weeds.
5. " NC1026 research has improved and strengthened the weed management recommendations of WeedSOFT and other decision-support software.
6. " Members of NC1026 are now working to include this research-based information into educational modules for a web-delivered version of WeedSOFT.
7. " NC1026 research created greater insight into how management strategies and environmental factors influence the degradation and longevity of weed seed banks.
8. " NC1026 researchers showed that weed emergence patterns are similar in different test locations even when seeds from one location are grown in a new environment.

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Report Information

Participants

Buhler, Doug (MI, Administrative Advisor); Cardina, John (OH); Clay, Sharon (SD); Davis, Adam (IL, USDA-ARS); Dekker, Jack (IA); Felix, Joel (OR); Forcella, Frank (MN, USDA-ARS); Horton, Sam (NE); Lindquist, John (NE); Ramirez, Analiza (Haydee) (KS); Renner, Karen (MI); Sprague, Christy (MI); Urbano, Jose (Sevilla, Spain, guest); Wyse, Don (MN)

Brief Summary of Minutes

The annual meeting was held at the Kellogg Biological Station, Hickory Corners, MI on July 28-29, 2009. The Administrator Advisor opened the meeting with a reminder that our current NC1026 project will expire as of September 2010 and that the rewriting process needs to begin to meet immediate deadlines (revised proposal submitted by December 2009). Based on discussion with ideas of a new direction for this project, a request for a 1-year project extension will be submitted. Researchers present at the meeting presented reports on research results from on-going and near completion studies that meet the project objectives. Data for the demographic study (Objective 1A) and the soil feedback study (Objective1B) have been compiled and reviewed. All sites have submitted soil samples for microbial analysis. Several different approaches to data analyses and summarization were discussed to guide manuscript preparation. Many ideas for the future direction of NC1026 project were discussed in preparation for the rewrite along with selection of a writing committee. Communication among the writing committee will continue through e-mail and conference calls. The next annual group meeting will be held in Champaign, IL area from July 26-28, 2010.

Accomplishments

The overarching goal of the NC1026 project and its multi-state group of collaborators is to use a more unified framework to incorporate risk in the development of weed management recommendations and decision support systems. Over the past year, researchers have conducted a fourth year of common field and greenhouse studies as part of understanding the population dynamics of two important weed species: common sunflower and giant ragweed, that differ in their distribution and competitiveness across the region. <br /> <br /> Five collaborators have conducted the demography study of common sunflower and giant ragweed in the field (Objective 1A) over the past three years. All data has been collected and summarized within a common format. The overall growth rates of populations of these two species appears to be very high in our experiments. The rich database of demographic parameters, including seedbank dynamics (germination, viability, and death of seed in the soil over different seasons) and seedling emergence, survival, mature plants, and seed production estimates allow for valuable comparison among site-years. These comparisons will allow for improved understanding of why these species occur with different distributions and competitiveness across the study region.<br /> <br /> Five sites also conducted the soil feedback study in the greenhouse using common accessions of the two weed species. Feedback scores, that is, plants grow well when grown and conditioned in their own soil, rather than soil of the other species, tended to follow local abundance and weediness characteristics. That is, common sunflower from Kansas had positive feedback scores in Kansas soil and conditions compared to giant ragweed grown in Kansas. Soil samples from each greenhouse pot have been collected and microbial analyses are being done to determine what influence they have on the feedback scores observed.<br /> <br /> Results from these two studies are providing valuable information about weed biology, competitiveness, and extent of variability across the region to assist in improvements of weed management decision support systems to provide greater reality and risk measures. This regional project continues to generate useful information to move beyond decision tools for herbicide selection only.<br />

Publications

Bonifas, K. D. and J. L. Lindquist. 2009. Effects of nitrogen supply on the root morphology of corn and velvetleaf. Journal of Plant Nutrition 32:1371-1382.<br /> <br /> Ramirez, A.H.M., A.M. Ndou, and J. A. Dille. 2008. Survey of common sunflower and giant ragweed populations in Kansas. North Central Weed Sci. Soc. Abstract 63:67. (Poster) <br /> <br /> Sieh, H., G. Reicks, and S.A. Clay. 2009. Influence of Corn on Seed Production of Giant Ragweed and Common Sunflower. South Dakota Academy of Science, April, 2009.<br />

Impact Statements

1. NC1026 collaborators organized and invited new individuals currently in the region to attend an open discussion on the future direction of the NC1026 project during the 2009 joint Weed Science Society of America/ Southern Weed Science Society annual meeting in Orlando, FL in February. Several people attended and additional ideas shared.
2. NC1026 collaborators and guests (14 individuals) participated in the annual meeting hosted by Michigan at the Kellogg Biological Station in Hickory Corners, MI. Research observations and data were presented and summarized. At this meeting, individuals were identified to prepare final reports and/or manuscripts based on these research results, a writing committee was formed and a new vice-chair for 2009-2010 project year was selected.
3. Research conducted by members of NC1026 has created greater insight into the dynamics of common sunflower and giant ragweed populations across the region, including seedbank, seedlings, mature plants, and seed production unique to each site but with a common regional trend.
4. Members of NC1026 are working to include these population dynamics insights into a weed management decision support system and into educational modules for users.

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Report Information

Participants

Adam Davis (IL, USDA-ARS); Brian Schutte (IL, USDA-ARS post-doctorate); Frank Forcella (MN, USDA-ARS); John Cardina (OH, USDA-ARS); John Lindquist (NE); Sharon Clay (SD); Anita Dille (KS); Christy Sprague (MI); Tony Yannarell (IL); Yi Lou (IL); Joel Felix (OR); Fabian Menalled (MT); Dave Stoltenberg (WI); Jack Dekker (IA); Doug Buhler (Administrative Advisor, MI)

Brief Summary of Minutes

Accomplishments

The overarching goal of the NC1026 Weed Biology project and its multi-state group of collaborators is to determine the importance of representing demographic realism within weed decision support systems and to facilitate incorporating the information that can best help to improve weed management decision-making. Starting in 2006, the NC1026 project has worked toward quantifying the demography of two model weed species, giant ragweed (Ambrosia trifida L.) and common sunflower (Helianthus annuus L.), across the North Central region. There are two main objectives in which this group has focused. The first objective has been to compare the relative importance of spatial variation in demographic rates at different levels of scale to inter-annual variation within sites (Objective 1a). Six collaborators conducted demography experiments over the course of three years. Over this past reporting session the NC1026 group has finished statistical analysis of the demographic data and has created an outline for a manuscript on Weed demography in the North Central Region. Preparation for publication of this manuscript has begun. The second objective that this group has focused on is the examination soil feedback mechanisms as they relate to variation in species demography (Objective 1b). Six collaborators including a soil microbiologist have been involved in conducting these experiments. During this past reporting session greenhouse experiments and analysis of the microbial communities associated with plant-soil feedback of the different soil conditioning treatments have been completed. The NC1062 group has begun the preparation of a manuscript that outlines the plant-soil feedback for two weeds of the North Central Region. One of the impacts of this NC1026 project has been the development of some of the first ever regional scale demography information on weeds important to agronomic systems. This information will help provide a means for assessing the importance of modifying the structure of decision support systems so as to incorporate a more realistic representation of the impact of weeds and how they respond to management. Additionally, an impact of this committee has been the development of a multi-state Agriculture and Food Research Initiative (AFRI) proposal that was been submitted this year.<br /> <br />

Publications

Darmency, H. and J. Dekker. 2010. Wild allies of foxtail millet (S. italica). In: Wealth of wild species: Role of plant genome elucidation and improvement, Volume 2; C. Kole (Ed.). Springer-Verlag, Berlin. (Invited review: In Press)<br /> <br /> <br /> Dekker, J. 2010. Evolutionary models of weed life history population dynamics. In: Advances in environmental research, Volume 10; J.A. Daniels (Ed.). Nova Science Publishers, Hauppauge, NY. (Invited review: In Press)<br />

Impact Statements

1. See accomplishments section.

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