Source: PENNSYLVANIA STATE UNIVERSITY submitted to NRP
ANTS AS KEY BUT OVERLOOKED PROVIDERS OF ECOSYSTEM SERVICES IN NO-TILL AGRICULTURE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
ACTIVE
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1032171
Grant No.
2024-67013-42317
Cumulative Award Amt.
$733,800.00
Proposal No.
2023-10089
Multistate No.
(N/A)
Project Start Date
Sep 15, 2024
Project End Date
Sep 14, 2027
Grant Year
2024
Program Code
[A1112]- Pests and Beneficial Species in Agricultural Production Systems
Recipient Organization
PENNSYLVANIA STATE UNIVERSITY
408 Old Main
UNIVERSITY PARK,PA 16802-1505
Performing Department
(N/A)
Non Technical Summary
The goal of this collaborative proposal is to characterize the overlooked role of ants in no-till agriculture. Ants are ecosystem engineers that define plant and animal communities near their nests. They act aboveground as predators, and belowground by manipulating soil properties. In tropical and subtropical agriculture, their roles have been well defined: they reduce populations of herbivorous insects and weeds and increase soil-nutrient availability. In contrast, the importance of ants is virtually unknown in temperate agricultural systems, like the U.S. Corn Belt. Ants have been largely ignored in this region because historic and ongoing use of tillage limits their abundance and persistence in crop fields. Adoption of no-till farming in some parts of the Corn Belt is providing ants an opportunity to colonize corn and soybean fields and exert their influence on above and belowground function.Our proposal is relevant for the "Pests and Beneficial Species" program because it advances for a key agricultural system knowledge of ants as beneficial species that could improve control of invertebrate pests and weeds while improving soil quality. The ultimate goal of this research is to encourage ant abundance, activity, and function in no-till agriculture to help improve sustainability of crop production.
Animal Health Component
60%
Research Effort Categories
Basic
40%
Applied
60%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2111510113030%
2161599107040%
2151820113030%
Knowledge Area
211 - Insects, Mites, and Other Arthropods Affecting Plants; 215 - Biological Control of Pests Affecting Plants; 216 - Integrated Pest Management Systems;

Subject Of Investigation
1510 - Corn; 1599 - Grain crops, general/other; 1820 - Soybean;

Field Of Science
1130 - Entomology and acarology; 1070 - Ecology;
Goals / Objectives
Objective 1: Define epigeal communities, including ants, present in no-till crop fields and the phenology of key community members.Objective 2: Determine the functional roles of ants in no-till systems.Objective 3: Determine responses of ants to a key agricultural management practice.
Project Methods
To achieve our three objectives, we will conduct a three-year factorial field experiment in PA and IN, which will be led by PI Tooker and co-PI Krupke, respectively, who have substantial experience running field experiments. Co-PIs Suarez and Yannarell will provide key methodological contributions, analyses, and interpretations of the samples we generate in our field experiments. Suarez, an ant ecologist, will assist with ant sampling, identification, gut content analyses, and experimental manipulations. Yannarell, a microbial ecologist, will facilitate soil analyses to understand how microbial communities change with ant activity and function.We will conduct one experiment across four different research farms: two in PA, two in IN, each in different growing regions. In PA, experiments will be in two distinct growing areas, separated by ~200 km: 1) RELARC (~800 ha; Centre Co.) in the Ridge and Valley Province of PA, and 2) Penn State's Southeast Agricultural Research and Extension Center (~120 ha SEAREC, Lancaster County) in the Piedmont Province. The fields in PA will not have been tilled for >20 yr and are typically cover cropped. In IN, we will establish experiments at two Purdue agricultural centers, Northeast Purdue Ag Center (NEPAC; in northeastern IN) and Throckmorton Purdue Ag Center (TPAC; in west-central IN), separated by 190 km and the fields will not have been tilled for >20 yr. Using four locations across the eastern and midwestern portions of the Corn Belt will provide a robust experimental design (8 replicates/state) and provide us with the opportunity analyze our results as one experiment, with state- or site-specific analyses as backup. Moreover, having locations in four growing areas will allow us to capture more of the available variability in ant populations and function, allowing our results to be more generalizable to more of the Corn Belt. To increase the potential to combine data across sites, the fields will have similar soil types. If possible, we will use fields that were recently in alfalfa for ?3 yr to minimize legacy effects. All the farms commonly use seeds coated with NSC, so we will measure neonic residues in each plot at the beginning and end of our 3-yr experiment (pyrethroids are not as persistent). At each location in a 1-ha section of a field, we will establish a 2×2 factorial experiment (4 treatments) in a Latin-square design (4 reps per treatment; 16 plots per site). The two factors will be presence/absence of 1) ants and 2) a winter cover crop. Plots will be 25×25-m to decrease the opportunity for species to move among plots, and we will have 5-m buffers between plots as additional buffers against movement. We will use the core 20×20-m for data collection. While much of our sampling (soil, arthropod communities) will be destructive, the large plot sizes will minimize the influence of sampling, as evidenced by previous work with similar-sized plots that detected treatment influences on epigeal communities and their functioning [21, 34, 92, 93]. Each year plots will occupy the same geo-referenced locations and "footprints" to capture cumulative effects of our treatments over the three-year project

Progress 09/15/24 to 09/14/25

Outputs
Target Audience:Farmers, extension and conservation district personnel, IPM practioners, other members of the agricultural community, research scientisits, including entomologists, soil scientists, and agronomists. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?In each state graduate students are using this project as the topic for their theses. In Pennsylvania, we are supporting a PhD student (Adegboyega Fajemisin), whereas at Purdue, we are supporting a MS student (Sophia Yager-Motl). The project is giving both students experience managing a field project with all the logistical and weather complications that field work involves. At Purdue, an undergraduate, summer hourly worker assisted with the project during the spring/summer season. All students are gaining expertise in logistics of crop production, experimentation, and team work. They are also gaining expertise in collecting and organizing experimental data, assessing ecological function of ants, as well as identification of insect samples from pitfall traps using taxonomic keys. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?In the next reporting period, we will conduct the second year of the experiment across all four sites; at each site, the plots will maintain the same footprints as we expect the strength of the effects from ants to build with each season. We will plant cover crops in half the plots in October/November of 2025. In 2026, the cash crop will be corn in Pennsylvania and soybeans in Indiana.

Impacts
What was accomplished under these goals? Objective 1: Define epigeal communities, including ants, present in no-till crop fields and the phenology of key community members. To complete our objectives, we established a two-by-two factorial experiment (four treatments, four replicates) at each of four research farms across Pennsylvania and Indiana (two farms per state). The two factors are 1) presence or absence of a cereal-rye cover crop before cash-crop planting and 2) normal or lower abundance of ants. To lower ant abundance in half of our plots, we poured boiling water on ant nests; to control for application of boiling water, in plots with normal abundance of ants we poured boiling water on the soil in locations without ant nests. We will repeat this manipulation of ants annually. The footprints of plots at each research farm will stay the same for each of the three years of our experiment. In 2025, the cash crop planted in Pennsylvania was soybeans, while in Indiana we planted corn. In Pennsylvania, the first year of the experiment occurred in 2024 when we planted corn, so 2025 is the first year that the project was funded by USDA, but it is the second year that we collected data. To define the epigeal communities in our plots in 2025, at the four field sites across Pennsylvania and Indiana, monthly (June, July, August, September) we characterized ants and the larger epigeal communities by baiting (pecan sandies and sugar water) for ants and deploying pitfall traps, which we collected after 72 h. Pitfall traps collected ants and other arthropods. We identified all ant specimens to species. We have identified most other arthropods to family, but we will identify ground beetles to genus. Objective 2: Determine the functional roles of ants in no-till systems. To determine how ants are interacting with their agroecosystem, at all four field sites, we characterized herbivore damage to the cash crop at growth stages V2 and V5 to understand the influence of ants and cover crops on crop damage. To assess predatory activity of ants and other members of the epigeal community, each month we measured predation of sentinel prey (waxworm caterpillars) and common weed seeds (yellow foxtail, common ragweed, and redroot pigweed). We are in process of sampling ant larvae for gut-content analysis so we can understand the food sources that ants are feeding to their larvae. This information will help us infer diet preferences of ant species. We are also in the process of collecting soil from ant nests to determine differences in nutrient quantity between baseline soil and soil with ant nests. Objective 3: Determine responses of ants to a key agricultural management practice. To determine ant responses to differences in agricultural management, we will analyze our data in the context of our factorial design, which includes presence or absence of cover crops. We expect cover crops to promote ant abundance and diversity, but we have yet to analyze our data because the field season and data collection is ongoing. Also, we took soil samples to quantify neonicotinoid concentrations across field conditions; neonicotinoid residues may linger from corn or soybean plantings in previous seasons.

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