RESILIENCE, STABILITY, AND PRODUCTIVITY: FROM CULTIVARS TO CROPPING SYSTEMS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: TERMINATED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1012474
• Project No.: WIS01986
• Project Start Date: Apr 1, 2017
• Project End Date: Mar 31, 2020

Project Director
Picasso Risso, VA, DA.

Recipient Organization
UNIV OF WISCONSIN
21 N PARK ST STE 6401
MADISON,WI 53715-1218

Performing Department
Agronomy

Non Technical Summary
In face of global climate change, productive, resilient, and stable agricultural systems are needed to endure increasingly frequent climatic crisis. Resilience is defined as the ability to withstand a crisis, and stability as the minimal long term variability in productivity. The goal of this project is to quantify and understand resilience and stability at three different scales in agricultural systems: a) at the genetic level (cultivars), b) at the plant community level (forage mixtures), and c) at the cropping system level (crop rotations). Mixed models analyses will be performed on long term datasets: a) alfalfa and grasses variety trials, b) forage mixtures experiments, and c) the Wisconsin Integrated Cropping Systems Trial. Quantitative measures for resilience and stability will be calculated. Cultivars, species combinations, and crop rotations which optimize resilience, stability and productivity will be identified. Hypotheses for a positive relationship between resilience and stability with specific level traits will be tested, including cultivar (e.g., disease resistance, cold tolerance), community (e.g., species and functional diversity and composition), and cropping systems (e.g., diversity, perenniality, management) traits. Results will inform farmers, plant breeders, and agronomists to develop systems more resilient to climate change and more profitable over the long term.

Animal Health Component

0%

Research Effort Categories

Basic

0%

Applied

100%

Developmental

0%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
203	1640	1070	50%
203	1610	1070	50%

Knowledge Area
203 - Plant Biological Efficiency and Abiotic Stresses Affecting Plants;

Subject Of Investigation
1640 - Alfalfa; 1610 - Pasture;

Field Of Science
1070 - Ecology;

Keywords

climate change

perennials

variability

yield

adaptation

Goals / Objectives
The main goal of this project is to provide methodological tools to study the stability and resilience of agricultural systems, in order to identify cultivars, species mixtures, and cropping systems that optimize these long term features. From a broad agroecological perspective, this project aims to identify the relationship and potential trade-offs between productivity, stability and resilience across agricultural systems scales, from cultivars to cropping systems.Objective 1. To identify forage cultivars that maximize resilience and stability, to identify cultivar traits associated with resilience and stability, and to study the relationship between productivity, stability and resilience at the cultivar level.Objective 2. To identify forage species mixtures that maximize resilience and stability, to identify forage mixture properties associated with resilience and stability, and to study the relationship between productivity, stability and resilience at the community level. Objective 3. To identify crop rotations that maximize resilience and stability, to study the relationship between crop rotation diversity and perenniality to resilience and stability, and to study the relationship between productivity, stability and resilience at the agroecosystem level.

Project Methods
Objective 1. Materials: The largest database of alfalfa cultivar trials was compiled by Dr. Dan Undersander at the University of Wisconsin-Madison, spanning between 1995 to 2013 across 12 states in the Midwest and Northeast United States and Canada, comprising 1,430 trials, 1,035 cultivars, and 28,070 data points. Cultivars are characterized by forage yield (productivity), multiple diseases and pest resistance, fall dormancy, and winter survival scores. Each cultivar was evaluated an average of 4 years. For this objective, we will use this database as the first step. Additionally, we will compile a database of other forage species trials, mainly forage grasses (e.g., Orchardgrass, tall fescue, meadow fescue, intermediate wheatgrass). This would require contacting individual breeders across the US, obtain datasets, and sometimes digitalizing databases that are not in digital format (e.g., historic farm bulletins).Variable operational definitions: The study of long term features of cultivars, is based on the distinction between "normal" and "crisis" years for each location. A crisis year for one location is the year in the historical series with minimum yield that coincides with a climatic stress (for instance, severe drought, identified from http://www.ncdc.noaa.gov/cag/). Normal years are all the other years in the series. Productivity is defined as the mean yield of each cultivar for each location, across all "normal years"; the higher the mean yield, the more productive is the cultivar. Stability is defined as the productivity divided by its standard error. Therefore, the lower the variability relative to the mean, the higher the stability, and the more stable is the cultivar. Resilience (R, Figure 3) is:R = (A / B) *100where, A is the yield in the crisis year (minimum yield of the series) and B is the productivity (mean of the normal years). Therefore, the higher the yield in the crisis year, expressed as percent of the productivity, the higher the resilience of that cultivar.Statistical Analyses: In order to calculate the values of productivity, stability and resilience, the following mixed model will be fit:Yield = Cultivar + Age + Trial + Location + Year + Location´Year + Location´Cultivar + Location´Cultivar´Yearwhere cultivar is the forage cultivar, age is the age of the stand (from 2 to 4 years), trial is the experiment, location is the site, and year is the calendar year that the harvest was conducted. All effects are fixed, except for trial which is random.In order to test the first hypothesis, the consistent differences will be observed on stability and resilience of different cultivars across similar sites, productivity, stability and resilience values for each cultivar in each location will be analyzed with an ANOVA, with the following mixed model: Y = Cultivar + Trial + Location + Cultivar´Location, where Y is the variable analyzed (productivity, stability, or resilience), cultivar is the forage cultivar (fixed effect), trial is the experiment (random effect), and location is the site (fixed effect). Multiple comparisons test for means of each cultivar and location will be performed to identify the cultivar with better performance in each variable. In order to test the second hypothesis that cultivars with increased tolerance to biotic and abiotic stresses (disease resistance, cold tolerance) will have higher stability and resilience, simple linear regressions will be performed of stability and resilience on disease and winter survival scores (traits that are specific of each cultivar). Finally, in order to test the third hypothesis that cultivar productivity will not be significantly associated with stability or resilience, simple linear regressions between productivity, stability, and resilience will be also fit for each location.Objective 2. Materials: A database of forage mixtures experiments across the US will be compiled, in collaboration with forage researchers from Universities and USDA. This would require an effort of contacting individual researchers across the US, obtaining the datasets, and adjusting formatting and variables in a consistent way. Some of the datasets which have already been confirmed are the ones form Picasso et al (2011), and Sanderson et al (2005, 2012). These datasets provide a basis for the analyses, but more datasets will be included.Statistical Analyses: In order to test the first hypothesis, that consistent differences will be observed on stability and resilience of different mixtures across similar sites, productivity, stability and resilience values for each cultivar in each location will be analyzed with an ANOVA, with the following mixed model: Y = Mixture + Trial + Rep (Trial) + Location + Mixture´Location, where Y is the variable analyzed (productivity, stability, or resilience), mixture is the forage mixture (fixed effect), trial is the experiment (random effect), rep is the replication nested in trial (random effect) and location is the site (fixed effect). Multiple comparisons test for means of each mixtures and location will be performed to identify the mixture with better performance in each variable. In order to test the second hypothesis that grass-legume mixtures will be more resilient and stable than monocultures contrasts will be estimated. Finally, in order to test the third hypothesis that mixture productivity will not be significantly associated with stability or resilience, simple linear regressions between productivity, stability, and resilience will be also calculated for each location.Objecitve 3. Materials: The Wisconsin Integrated Cropping Systems Trial (WICST) at the University of Wisconsin - Madison, was established in 1989 in response to farmers and others concerns for long-term research on low-input farming. WICST goal is to research on the productivity, profitability and environmental impacts of crop rotations with contrasting management. Over the past 26 years, WICST generated a large database on 60 acres of land at the UW-Madison Arlington Agricultural Research Station comparing conventional and organic cash grain and dairy forage systems, with various levels of diversity and perenniality (Sanford et al, 2012). The WICST 26 years of yield data will be used as primary database for this third objective. As part of the project, other long term crop rotation experiments in the region will be considered and other datasets added to the analyses.Statistical Analyses: In order to test the first hypothesis, that consistent differences will be observed on stability and resilience of different crop rotations, productivity, stability and resilience values for each crop in each rotation will be analyzed with an ANOVA, with the following mixed model: Y = Rotation + Rep, where Y is the variable analyzed (productivity, stability, or resilience), rotation is the crop rotation (fixed effect), rep is the replication (random effect). Multiple comparisons test for means of each mixtures and location will be performed to identify the rotation with better performance in each variable. In order to test the second hypothesis that rotations with higher diversity and perenniality will be more resilient and stable than annual monocultures contrasts will be estimated. Finally, in order to test the third hypothesis that crop productivity will not be significantly associated with stability or resilience, simple linear regressions between productivity, stability, and resilience will be also calculated.

Progress 04/01/17 to 03/31/20

Outputs
Target Audience:Audiences are: undergraduate and graduate students, researchers, extension agents, farmers, agriculture agencies, and ag industry. Changes/Problems:The initial objective 2 intended to study resilience and stability in forage crop mixtures. However, data availability for accomplishing this goal was lower than anticipated, so we decided to analyze resilience and stability of an annual cereal crop instead, where data was abundant. This change did not affect the overall outcomes of the project. What opportunities for training and professional development has the project provided?The project supported the training of one MSc student in Plant Breeding and Plant Genetics at University of Wisconsin - Madison. How have the results been disseminated to communities of interest?Results were presented in the ASA-CSSA-SSSA annual meetings for 3 years, including an invited presentation at the ASA-CSSA-SSSA on-line meeting in 2020. Results were presented in lab meetings, seminars, and courses at UW - Madison, and at field days at University of Wisconsin- Madison Agricultural Research Stations. Results were also presented at North Central Coordinating Committee on Ecophysiology of forages (NCCC-31) annual meetings for three years. 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 challenges that agriculture faces are growing, and so is the interest from scientists and decision makers for developing sustainable, productive, stable, and resilient systems. This project provided new methodological and conceptual tools to understand the biological foundations of cropping system resilience to climate change. Resilience is the capacity of a system to withstand and recover from a climate crisis. Stability is the minimal variability of crop yield across years. Understanding the biological basis of resilience and stability is key for climate change adaptation. We have led the development of novel methods to quantitatively measure resilience and stability (Picasso et al., 2019), and to identify the biological mechanisms driving resilience and stability from cultivars to agroecosystems. At the crop level, analyzing longitudinal data of alfalfa cultivar yields in North America, we found that resilience was associated with fall dormancy but stability with disease resistance, establishing that there are different biological mechanisms driving stability and resilience (Picasso et al., 2019). At the agroecosystem level, using longitudinal data from the Wisconsin Integrated Cropping Systems Trial we found that systems with greater perenniality were more stable and crop diversity increased drought resilience (Sanford et al., 2021). Objective 1 was accomplished. A paper on Resilience and Stability of alfalfa cultivars in North America was published in Crop Science (Picasso et al., 2019). This paper was awarded Crop Science Outstanding Paper Award for the Forage and Grazinglands division (C6- CSSA). We found that alfalfa cultivars differ in stability and resilience and that these variables represent two very different dimensions of the long-term performance of cultivars. Productivity, stability, and resilience were different among cultivars across locations, showing that some cultivars were consistently superior for each variable. For instance, cultivars 'Abundance', '5454', and '631' were highly resilient cultivars, and 'OneidaVR', '5312', and 'Vernal' were highly stable, and this was consistent across locations. Cultivar stability was not associated with productivity, and it was negatively associated with disease resistance. Cultivar resilience was negatively associated with productivity, and not associated with other traits. Cultivar productivity has increased with year of release of cultivar, stability has not changed, and resilience has decreased. Coordinated testing approach across many locations is proposed to improve alfalfa resilience in the future. The methodology proposed in this paper can be applied in the future to other crops and cropping systems, to advance the understanding of the long-term performance of agricultural systems in the face of an increasingly changing climate. Objective 2 was accomplished (modified): This objective was modified to identify oat cultivars that maximize stability and resilience, using the methodology developed in Objective 1. A MSc student on Plant Breeding and Plant Genetics at UW-Madison graduated on this project. A paper was submitted evaluating phenotypic variation for resilience and stability of grain yield in oat (Avena sativa L.) genotypes and assessing the association between resilience, stability, and yield. Grain yield data of 2,904 oat genotypes evaluated in variety trials across 21 years and seven locations (137 location-year, environments) in Wisconsin (USA) were used. Climatic crises were identified for specific years and locations. All crisis incidents were related to drought, and some also included heat stress. Significant genetic variation for resilience and stability was found, and these two traits were positively correlated in most locations and across locations. However, some genotypes with relatively high resilience and low stability were identified, and also some genotypes with relatively low stability and high resilience. Genotypic mean grain yield was not associated with resilience or stability. These results show that resilience and stability are complementary traits to select for adaptation to climate change in cereals. Objective 3 was accomplished: Analyses of the Wisconsin Integrated Cropping Systems Trial database were completed, and resilience and stability from the energy output of the crop rotations was estimated. A paper was published in Field Crops Research (Sanford et al., 2021). We found that drought resilience differed significantly among cropping systems with the least resilient system (continuous maize) producing just 79% of expected output, followed by maize-3 years of alfalfa producing 94% of output during the drought year. Resilience among the remaining four systems under drought was not significantly different from 100%. Resilience to excess moisture differed significantly among cropping systems and it was consistently lower in the forage systems with maize-3 years of alfalfa, flowed by pasture, and finally maize-oats- 2 years of alfalfa. Cropping system stability was not associated with resilience to drought or to excess moisture. Resilience to drought was not associated with resilience to excess moisture. This provides further empirical evidence that stability and resilience are different and complementary dimensions of the performance of cropping systems in face of climate change, and they are explained by different traits. Furthermore, resilience to drought and resilience to excess moisture were not associated, which suggests that it is necessary to evaluate more than one resilience indicator when comparing cropping systems. Stability was positively and linearly associated with the relative perenniality (i.e. the combination of increased continuous living cover and reduced tillage) of cropping systems. Stability was also negatively linearly associated with relative tillage, and positively associated with relative cover. Drought resilience was positively associated with relative diversity and the best model to fit the relationship was a logistic function achieving the maximum resilience with 3 species in the crop rotation. Resilience to excess moisture was not associated with perenniality or diversity and negatively associated with soil cover. These results suggest that cropping systems with increased levels of diversity and perenniality are needed for optimizing stability and resilience of cropping systems outputs.

Publications

• Type: Journal Articles Status: Published Year Published: 2021 Citation: Sanford, G.R., R. Jackson, E. Booth, J.L. Hedtcke, and V. Picasso. 2021. Perenniality and diversity drive output stability and resilience in a 26-year cropping systems experiment. Field Crops Research 263: 108071. doi: 10.1016/j.fcr.2021.108071

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:Audiences are: undergraduate and graduate students, researchers, extension agents, farmers, agriculture agencies, and ag industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project supported one graduate student during her MSc. How have the results been disseminated to communities of interest?Results were presented in the ASA-CSSA-SSSA annual meetings in San Antonio, TX. Results were presented in lab meetings and seminars at UW - Madison, and at field days in West Madison ARS. What do you plan to do during the next reporting period to accomplish the goals?In the next reporting period, which is the final year, we will submit the two papers that are in preparation.

Impacts
What was accomplished under these goals? Objective 1 was accomplished: The paper on Resilience and Stability of alfalfa cultivars was published in Crop Science. The challenges that agriculture faces are growing, and so is the interest from scientists and decision makers for developing sustainable, productive, stable, and resilient systems. We found that alfalfa cultivars differ in stability and resilience and that these variables represent two very different dimensions of the long-term performance of cultivars. Productivity, stability, and resilience were different among cultivars across locations, showing that some cultivars were consistently superior for each variable. For instance, cultivars 'Abundance', '5454', and '631' were highly resilient cultivars, and 'OneidaVR', '5312', and 'Vernal' were highly stable, and this was consistent across locations. Cultivar stability was not associated with productivity, and it was negatively associated with disease resistance. Cultivar resilience was negatively associated with productivity, and not associated with other traits. Cultivar productivity has increased with year of release of cultivar, stability has not changed, and resilience has decreased. coordinated testing approach across many locations is proposed to improve alfalfa resilience in the future. The methodology proposed in this paper can be applied in the future to other crops and cropping systems, to advance the understanding of the long-term performance of agricultural systems in the face of an increasingly changing climate. Objective 2 was accomplished (modified): As was described in previous report, this objective was modified to identify oat cultivars that maximize stability and resilience. The graduate student working on this project advanced with the analyses and gave a presentation at the ASA-CSSA-SSSA annual meetings in San Antonio. She is finishing her thesis and expected to defend it in February this year. A paper will be submitted after her defense. Objective 3 was accomplished: Analyses of the WICST database were completed, and resilience and stability from the energy output of the cros rotations was estimated. A paper is in draft form and will be submitted for publication this month. We found: Drought resilience differed significantly among cropping systems with the least resilient system (continuous maize) producing just 79% of expected output, followed by maize-3 years of alfalfa producing 94% of output during the drought year. Resilience among the remaining four systems under drought was not significantly different from 100%. Resilience to excess moisture differed significantly among cropping systems and it was consistently lower in the forage systems with maize-3 years of alfalfa, flowed by pasture, and finally maize-oats- 2 years of alfalfa. Cropping system stability was not associated with resilience to drought or to excess moisture. Resilience to drought was not associated with resilience to excess moisture. This provides further empirical evidence that stability and resilience are different and complementary dimensions of the performance of cropping systems in face of climate change, and they are explained by different traits. Furthermore, resilience to drought and resilience to excess moisture were not associated, which suggests that it is necessary to evaluate more than one resilience indicator when comparing cropping systems. Stability was positively and linearly associated with the relative perenniality (i.e. the combination of increased continuous living cover and reduced tillage) of cropping systems. Stability was also negatively linearly associated with relative tillage, and positively associated with relative cover. Drought resilience was positively associated with relative diversity and the best model to fit the relationship was a logistic function achieving the maximum resilience with 3 species in the crop rotation. Resilience to excess moisture was not associated with perenniality or diversity and negatively associated with soil cover. These results suggest that cropping systems with increased levels of diversity and perenniality are needed for optimizing stability and resilience of cropping systems outputs.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Bullock, S.; L. Gutierrez, V. Picasso. 2019. Resilience and Stability of Oats to Climate Variability. ASA-CSSA annual meetings, San Antonio, TX, USA.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Picasso, V., M. Casler, D. Undersander. 2019. Resilience, Stability, and Productivity of Alfalfa (Medicago sativa L.) Cultivars in Rainfed Regions of North America. Crop Science. 59:111. DOI: 10.2135/cropsci2018.06.0372

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:The target audience included: graduate students, postdocs, professors and scientists in Agronomy, Crop Science, Forage Science, Plant Breeding, and Agroecology. We also reached plant breeders and extension agents from alfalfa and forage industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One graduate student is being trained on this project. How have the results been disseminated to communities of interest?Results have been disseminated by: 1) At national and international conferences, two oral presentations were presented to graduate students, postdocs, plant breeders, and researchers in plant sciences, forage science, and agroecology. 2) Meetings with forage breeders from private companies were conducted to explain the results and develop collaborations for future research. What do you plan to do during the next reporting period to accomplish the goals?I plan to publish a paper from Objective 2 and Objective 3 and finalize analyses.

Impacts
What was accomplished under these goals? Objective 1 was fully accomplished: The paper on Resilience and stability of alfalfa cultivars in North America is published in Crop Science. Historic data from alfalfa cultivar trials from 12 states, over the last 20 years, was analyzed using a mixed models approach. Major climatic events (e.g., droughts) were identified for each location. Quantitative measures for resilience and stability for each cultivar were calculated for each location. Differences in resilience and stability were quantified allowing to identify cultivars with different long-term features. This provided information to breed and choose cultivars that can be profitable over the long term. The impact of this results was very high for both the alfalfa industry and the research community. First, the major seed companies from the alfalfa industry got interested in our results on resilience, and provided letters of support and seeds for continuing and expanding this line of research. Second, based on the results of this project, we proposed to update and expand the alfalfa cultivars database, collaborating with a larger team of forage breeders, start field experiments to test resilience results empirically, and use crop modeling as a new tool. This project has now been supported by NIFA-AFRP. Objective 2 is ongoing: We are collaborating with various forage researchers interested in evaluating resilience in other forages like cool season (Fescue and Oats) and warm season (Switchgrass) grasses. Given the interest from breeders, and availability of data on different grass species, we may focus on expanding the resilience work on grass species, rather than focusing on the initially proposed community level studies of forage mixtures. Objective 3 is ongoing: Final analyses of the WICST database were completed and presented in a Conference in Rothamsted, UK. Corn yields of various rotations from the WICST were preliminary used to calculate resilience and stability, and compared across organic and conventional rotations. The paper is in draft form and we expect to have it published this coming year.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Picasso, V., M. Casler, D. Undersander. 2019. Resilience, Stability, and Productivity of Alfalfa (Medicago sativa L.) Cultivars in Rainfed Regions of North America. Crop Science. doi:10.2135/cropsci2018.06.0372
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Picasso, V., M.C. Casler and D. Undersander. 2018. Resilience, stability and productivity of alfalfa in North America. North American Alfalfa Improvement Conference, Logan, UT, USA.
• Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Sanford, G., E. Booth, V. Picasso, and R. Jackson. 2018. Agroecosystems for an uncertain future. The Future of Long-Term Agricultural Experiments. Rothamsted, UK.

Progress 04/01/17 to 09/30/17

Outputs
Target Audience:Graduate students and scientists in Agronomy, Crop Science, and Agroecology. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One graduate student was trained on this project. How have the results been disseminated to communities of interest?At local and international conferences, two oral presentations were presented to graduate students and scientists in plant sciences and agroecology. What do you plan to do during the next reporting period to accomplish the goals?I plan to publish the results from Objective 1 and Objective 3, and start the data analyses for Objective 2. One graduate student will be devoted full time to this project starting next year.

Impacts
What was accomplished under these goals? Objective 1 was accomplished: Data analyses of the alfalfa database was finished and the paper on Resilience and Stability of alfalfa cultivars is in a draft form. Historic data from alfalfa cultivar trials from 12 states, over the last 20 years, was analyzed using a mixed models approach. Major climatic events (e.g., droughts) were identified for each location. Quantitative measures for resilience and stability for each cultivar were calculated for each location. Differences in resilience and stability were quantified allowing to identify cultivars with different long-term features. This provided information to breed and choose cultivars that can be profitable over the long term. This paper will be submitted to Crop Science in the next month. Objective 2 was started: Contacts were made to compile the forages database with forages researchers across the USA, from USDA and Universities. Several researchers responded positively to the invitation to collaborate on this project. The data compilation and analysis will start next year. Objective 3 was started: Preliminary analyses of the WICST database were completed and presented in the ASA-CSSA-SSSA annual meetings in Tampa. Corn yields of various rotations from the WICST were preliminary used to calculate resilience and stability, and compared across organic and conventional rotations. Ongoing analyses are incorporating better methods for estimating yields and will be ready for publication within the coming year.

Publications

• Type: Conference Papers and Presentations Status: Accepted Year Published: 2017 Citation: Picasso, V. and G. Sanford. 2017. Resilience, Stability and Productivity in Crop & Livestock Systems. ASA-CSSA-SSSA annual meetings, Tampa, FL, USA.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2017 Citation: Picasso. V. 2017. The last supper talk: sustainability and resiliency from perennial forage systems. Center for Integrated Agricultural Systems, UW Madison, Citizen Advisory Council, Madison, WI, USA.