About

Mary Rogers is a faculty member in the Department of Entomology at the University of Minnesota. Her research focuses on the biology and ecology of insects, with specific interest in parasitoid wasps and their applications in biological control. She is involved in studying pollinator biodiversity in remnant and restored prairies, including the conservation and management of native bees such as bumble bees, and the impacts of environmental changes on forest biodiversity, exemplified by her work on the Emerald Ash Borer. Her work also encompasses the genetics of insect-host relationships, insect resistance mechanisms, and integrated pest management strategies. As an advisor, she mentors graduate students in various projects related to insect biology, ecology, and control methods, contributing to the advancement of sustainable entomological practices and pollinator conservation.

Research topics

• Horticulture
• Ecology
• Biology
• Agronomy
• Agroforestry
• Demography
• Engineering
• Aeronautics
• Simulation
• Environmental science
• Biotechnology
• Zoology
• Aerospace engineering

Selected publications

• Where Are We Today? State of Organic Agriculture Education and Technical Programs: Proceedings from the ASHS Organic Interest Group 2025 Workshop

  HortTechnology · 2026-03-10

  articleOpen access

  Universities vary greatly in their organic agriculture education programs, with differences in student interest in studying organic production and food systems, classes offered, and infrastructure and facilities. The organic agriculture curriculum options are also evolving as a result of departmental or college-level curriculum revisions. Similarly, the technical assistance provided for growers varies from state to state. Recent US Department of Agriculture–Agricultural Marketing Service Transition to Organic Partnership Program programming has created more interest in providing and growing this assistance. The workshop “Where are we today? State of Organic Education and Technical Programs” was conducted at the 2025 American Society for Horticultural Science Conference in New Orleans, LA, USA, and featured a panel of teaching and extension scholars who provided insights into the existing programs and challenges that are currently affecting organic production across the United States. This workshop focused on discussing the challenges to organic agriculture education both at the undergraduate and farmer levels, and opportunities for growth.

  PublisherDOI

• Evaluating Real-Time PCR to Quantify Drosophila suzukii Infestation of Fruit Crops

  Insects · 2026-01-16

  articleOpen access

  Common methods for detecting Drosophila suzukii (spotted-wing drosophila, SWD) in fruit, such as microscopy, physical extraction, and incubation, are time-consuming and may underrepresent egg and first instar larvae counts, the smallest life stages of SWD. To address these limitations, we evaluated a quantitative real-time PCR (qPCR) protocol to detect and quantify SWD eggs using a linear model of the log-transformed ratio of eggs to sample volume (µL) in Tris buffer and fruit tissue. Compared to traditional approaches, this method reduces identification time from several weeks to approximately five hours. We observed a negative linear correlation between qPCR cycle threshold and egg concentration in both standard and fruit tissue samples, with similar model fits (R2 = 0.7215 for field fruit tissue; R2 = 0.874 for standard samples). This DNA-based protocol improves infestation detection speed and accuracy by enabling rapid, species-specific identification of D. suzukii in fruit tissue, addressing limitations of morphological identification of eggs and larvae. Further refinement for fruit tissue could enhance real-world applicability. Rapid detection may enable timely assessment of varietal resistance to SWD and support safer control strategies targeting early life stages, helping to prevent pest development and fruit degradation.

  PublisherOA PDFDOI

• Economic Analysis of Biodegradable Paper versus Plastic Mulch for Organic Day-neutral Strawberry Production in the Upper Midwest

  HortTechnology · 2025-06-10 · 3 citations

  articleOpen accessSenior author

  Field trials were conducted in Minnesota and Wisconsin during 2022–2023 to evaluate production costs and net returns associated with a soil biodegradable paper mulch compared to three polyethylene (PE) plastic mulches in an organic day-neutral (DN) strawberry system. Assessing the economic viability of soil biodegradable mulch is critical for organic growers who may need to transition away from PE plastic mulches to comply with USDA-AMS National Organic Program (NOP) standards. To date, no published research has directly compared the economic performance of NOP-compliant biodegradable paper mulch in organic strawberry production. Our results indicate that while the paper mulch incurred higher initial costs and required more labor for weather-related maintenance, it yielded positive net returns when DN strawberries were marketed through direct-to-consumer channels at premium prices. Despite being the least profitable option overall, the biodegradable paper mulch represents an economically viable alternative to PE mulches under certain market conditions and offers promise for future NOP-compliant organic production systems.

  PublisherDOI

• Impact of Mulches on Floral Visitors in Day‐Neutral Strawberries and Contribution of Syrphid Flies to Strawberry Pollination

  Journal of Applied Entomology · 2025-05-06

  articleOpen access

  ABSTRACT Animal‐mediated pollination is essential for the production of many specialty crops, with insects, primarily bees, serving as the predominant pollinators in many agroecosystems. However, increasing management problems with honey bees and declines in native bee populations due to various environmental stressors have highlighted the importance of promoting wild bees and other insect pollinators to ensure sustainable pollination services. This study explores the impact of various mulches on the abundance and richness of floral visitations by insects and the role of syrphid flies in a day‐neutral strawberry system. Four different types of mulches were evaluated at the University of Wisconsin West Madison Agricultural Research Station in Wisconsin, USA , during the 2022 and 2023 growing seasons, and included three polyethylene mulches of different colour (black, white on black, and reflective metallic) and one brown soil‐biodegradable paper mulch. Observations of pollinator floral visitations were conducted, and insects were grouped into broad morphotypes. In addition, syrphid flies were sampled to assess their pollen loads. Mulch type did not significantly affect the overall abundance or richness of pollinators visiting flowers. Syrphid flies were the most abundant floral visitors, followed by small dark bees, green bees, Orius spp., and honey bees, while Bombus spp. were found in low numbers. Toxomerus marginatus , the margined calligrapher, was the most abundant syrphid species collected, representing 72% of all syrphid flies collected. Overall, 31% of syrphid flies captured carried strawberry pollen. A few syrphid species carried significant amounts (> 200 grains) of strawberry pollen on their body. The findings suggest that while mulch type did not impact pollinator visitation, syrphid flies may be important for strawberry pollination, as they were abundant, at least in 2022, and carry strawberry pollen. Our results underscore the need for further research to understand the complex role of non‐bee pollinators in strawberry pollination and to further investigate the role of syrphid flies as pollinators in different agroecosystems.

  PublisherOA PDFDOI

• Swede Midge (Contarinia nasturtii Keiffer) Phenology and Management in Minnesota Community Gardens

  HortScience · 2025-01-31 · 1 citations

  articleOpen access

  Swede midge is a major insect pest of brassicas, including broccoli ( Brassica oleracea L. var. italica) , cauliflower ( B. oleracea L. var. botrytis ), collards ( B. oleracea L. var. viridis ), and kale ( B. oleracea var. sabellica ). The insect infests and feeds on the growing tips of plants, resulting in distorted leaves or lack of heading of broccoli and cauliflower. Since 2014, when continuous trapping began in Minnesota, USA, it has primarily been found in community gardens in the Twin Cities metropolitan area. Trapping data obtained at Saint Paul community gardens over 3 years indicated that swede midge phenology in any particular garden varied from year to year. Gardeners surveyed in 2023 indicated some knowledge of swede midge, were unsure of how to recognize infestation symptoms, and were interested in collaborating to test management methods. A simple mitigation system using bamboo poles, polypropylene fabric, and weed barrier was tested for its ability to reduce infestations by blocking access to plants by adults and to soil by larvae and prevent emergence by previously pupating generations. It was 50% to 80% effective compared with unprotected controls.

  PublisherDOI

• Ecological effects of interplanted sweet alyssum and alfalfa in an organic day-neutral strawberry production system

  Frontiers in Ecology and Evolution · 2025-11-12

  articleOpen accessSenior author

  Production of day-neutral strawberries ( Fragaria x ananassa ) is increasing in the Upper Midwest region of the USA, resulting in an extended strawberry harvest season compared to traditional June-bearing production systems. However, the longer harvest season comes with additional insect pest pressure and the need for novel integrated pest management strategies. Spotted-wing drosophila ( Drosophila suzukii ; SWD) and tarnished plant bug ( Lygus lineolaris ; TPB) can decrease strawberry yield and fruit quality. Insecticides are the dominant management strategy for both insect pests; however, fewer effective insecticides are available in organic production systems. Interplanting is an integrated pest management strategy which can provide conservation biological control and may repel or attract species of interest through volatile organic compound (VOCs) emissions. We investigated the effect of interplanting alfalfa and sweet alyssum with day-neutral strawberry plants on fruit yield and quality, SWD infestation and TPB damage, arthropod abundance and diversity. Additionally, we measured the relative abundance of sweet alyssum VOCs, acetophenone and benzaldehyde, in the field because they may be aversive to SWD adults. The interplanting treatment inconsistently affected fruit production; in year one of the study, the control treatment had larger fruit than the other two treatments and, in year two, berries interplanted with sweet alyssum had more marketable yield than the other two treatments. Treatments did not affect SWD infestation or TPB damage. Acetophenone and benzaldehyde VOC production varied in the sweet alyssum plots by time of day and date. The control treatment had less arthropod abundance and diversity compared to the intercrop treatments. Intercropping may provide resources for arthropod communities but may not reduce key pest species such as SWD and TPB in day-neutral strawberries.

  PublisherOA PDFDOI

• Efficacy and Economic Viability of Organic Control Methods for Spotted-wing Drosophila in Day-neutral Strawberry Production in the Upper Midwest

  HortTechnology · 2024-09-13 · 4 citations

  articleOpen accessSenior author

  Day-neutral strawberry (DNS) production is increasing in the Upper Midwest because of its extended harvest season and greater yield over June-bearing cultivars. However, the longer season increases fruit exposure to the invasive spotted-wing drosophila ( Drosophila suzukii ; SWD), which threatens the production of small fruits and berries, particularly in organic systems. Numerous pest management tactics have been developed for SWD in recent years; however, relatively few studies have investigated the impact of SWD on DNS. Organic DNS growers need information regarding which management strategy is most effective when compared directly. To address this knowledge gap, we established a 2-year controlled field experiment with organic DNS. We applied treatments that correspond with techniques that local growers reported using or that have shown promise for organic raspberries, including increased harvest frequency, botanical-based repellents, and weekly rotations of organic insecticides, which we compared with an untreated control. We hypothesized that noninsecticidal SWD management strategies would result in fewer SWD eggs per berry and a lower proportion of infested berries compared with those associated with an untreated control. We also hypothesized that noninsecticidal management strategies would be as effective and cost less than organic insecticide applications. We collected data regarding labor hours, direct costs, strawberry yield, and SWD infestation in experimental plots on certified organic land in Minnesota in 2022 and 2023. An average of 33% of strawberries contained SWD eggs. The experimental treatments showed inconsistent effectiveness for reducing infestation compared with that of the untreated control plots and had no effect on marketable plant yield over the 2-year period. Thus, the added labor expense of these pest control treatments yielded net returns that were 17% to 21% below the control. Labor-saving alternatives like exclusion netting or postharvest cold treatments, which reduce fruit pest exposure and egg viability without harming nontarget insects, may offer more cost-effective solutions for managing SWD in organic DNS.

  PublisherDOI

• Predicting the growth trajectory and yield of greenhouse strawberries based on knowledge-guided computer vision

  Computers and Electronics in Agriculture · 2024-04-10 · 10 citations

  article
  PublisherDOI

• Detection of Spotted-winged Drosophila (Diptera: Drosophilidae) Infestations in Blueberry Fruits1

  Journal of Entomological Science · 2023-06-26 · 1 citations

  articleOpen access

  Spotted-winged drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), has become a significant pest of small and stone fruit. Unlike most Drosophila species, it tends to infest healthy, intact ripe fruit, as opposed to rotting or overripe fruit (Mitsui et al. 2006, Popul. Ecol. 48:233–237; Asplen et al. 2015, J. Pest Sci. 88:469–494). Spotted-winged drosophila adults are typically detected in the field using baited traps. This is useful in helping growers decide when to apply insecticides (Ebbenga et al. 2022, J. Entomol. Sci. 57: 516–529), but methods are also needed to estimate actual fruit infestation levels. Spectral imaging of fruit may provide a nondestructive alternative to extraction of larvae and could provide information on the infestation status of a single fruit. Such imaging has been tested for insect pests other than D. suzukii. For example, Peshlov et al. (2009, J. Near Infrared Spectrosc. 17:203–212) used near-infrared spectroscopy (NIRS) to detect infestation of wild blueberries (Vaccinium) by blueberry maggot, Rhagoletis mendax Curran (Diptera: Tephritidae). By measuring spectra of a live larva and subtracting it from an infested blueberry, they demonstrated that the NIR signal they recorded was from a larva and “associated chemical changes in the blueberries.” Detectable differences between infested blueberry and larvae occurred between approximately 750 and 1300 nm, with a small differential signal at 600 nm. Tsuta et al. (2006, Food Sci. Technol. Res. 12:96–100) also used spectroscopy to discriminate between blueberry fruit and “foreign substances.” They measured the spectra of various foreign substances, including worms, separately from the fruit. They detected a difference in the second derivative of absorbance between worms and berries between approximately 625 and 675 nm.The F-750 Produce Quality Meter (Felix Instruments, Camas, WA) is a handheld visible and near-infrared spectrometer that has been used to predict ripeness of various fruit correlated with fruit constituents, such as dry matter content of cherry, Prunus avium L. (Toivonen et al. 2017, Can. J. Plant Sci. 97:1030–1035). Light transmitted from the device's xenon tungsten lamp interacts with the scanned object and then is transmitted near the zone of illumination where the signal is recorded. The portability of this device allows its use in agricultural fields and may be useful beyond postharvest fruit quality determination. Infestation levels of D. suzukii eggs and first instars are undetectable by the human eye. If the F-750 meter is capable of distinguishing infested from uninfested fruit, the device would allow sorting or culling by small-acreage farmers who may not have storage facilities cold enough to arrest D. suzukii development (Aly et al. 2017, J. Econ. Entom. 110:87–93). This work was conducted to determine to what extent infestation can be detected using the F-750 spectrometer in blueberries and raspberries (Rubus).To test the possibility that the F-750 spectrometer could be used to detect D. suzukii, in-field infestation assays and artificial infestation assays with store-bought blueberry fruit in the laboratory were initiated. For field infestation samples, ‘Northblue’ and ‘Chippewa’ blueberries (V. corymbosumL.ｘV. angustifoliumAit.) were harvested from the Sand Plain Research Farm of the University of Minnesota in Becker, MN (45°23′36.42′’N, 93°52′36.3′’W). Berries were collected weekly between 5 and 26 July 2017 (100 in week 1 and then 50 each in weeks 2, 3, and 4), scanned with the F-750 spectrometer in the laboratory, and then placed in 30-mL containers (Dart Container Corp., Mason, MI), with one fruit per container. The containers were incubated at room temperature (21–23°C), and fly emergence was recorded 1 wk later.Artificial infestation assays were initiated with store-bought blueberry fruit in the laboratory. Blueberries were purchased from a grocery store, and berries with disease, previous insect infestation, or turgor loss were discarded prior to artificial infestation. Scans of fruit that were infested were compared with that of uninfested fruit and fruit that were uninfested but poked using an insect pin (BioQuip Insect Pins, Black, #0, Bioquip Products, Rancho Dominguez, CA) to simulate ovipositor injury without the presence of eggs or larvae. To infest fruit, individual berries were incubated with two mated D. suzukii females for 24 h in 30-mL clear plastic containers with a square of filter paper to absorb excess liquid. Adult flies were removed after 24 h, after which all containers were placed in a growth chamber at 23–25°C, with a 16-h light:8-h dark photoperiod. Individual fruits were scanned 4 or 7 d after infestation. Control treatments included (1) fruit not poked and not infested and (2) poked but not infested.One-way blind tests were conducted in 2021. Intact fruit were rinsed three times with deionized water, air dried, dipped in 2% (v/v) propionic acid (Fisher Scientific, Hampton, NH) for 5 s to inhibit mold growth, air dried, and then poked with an insect pin to provide ovipositor entry sites. Individual fruits were placed in 30-mL containers and randomly assigned to an infested or uninfested category using R statistical software. Five female and five male (to insure mating) flies, approximately 3 d old, were added to each “infested” treatment container. No flies were added to containers serving as untreated controls. All containers were placed in a growth chamber kept at 23–25°C, with a 16-h light: 8-h dark photoperiod. After 36 h, flies were removed, and berries were viewed under a stereo microscope to check for the presence of egg breathing filaments. Containers of berries were then delivered to the scanner who did not know which containers contained infested fruit. Fruits were scanned 48, 72, and 120 h after initial infestation and scored for larval emergence 7 d after introduction to D. suzukii adults.Each berry was scanned once with the F-750 Produce Quality Meter. Blueberries were scanned with pedicel-ends down on the light-emitting surface. A ring was fabricated from Delrin acetal homopolymer (DuPont, Wilmington, DE, USA) to fit on top of the 11-mm reflector cone to improve the support of berries over the central ring of the small fruit adapter provided by the manufacturer. Only the machine-computed second derivatives of absorbance data were collected. The routine used by the F-750 meter can be explained as a nine-point second order Savitzky-Golay filter (Savitzky and Golay 1964, Anal. Chem. 36:1627–1639).The accuracy rates of one-way blind predictive tests were conducted according to Hodgson et al. (2004, J. Econ. Entomol. 97:2127–2136). The probability of making a correct determination of infestation across all data sets = Rpi (true positivesi+true negativesi), where pi is the proportion of n data sets represented by set i; true positivesi is the probability of correctly identifying infestation; and true negativesi is the probability of correctly identifying no infestation. Because there were seven data sets of similar size (50–99 berries), pi = 0.143.Field-harvested ‘Chippewa’ and ‘Northblue’ (Fig. 1A) berries showed similar patterns of spectral changes with harvest week. Mean second derivatives of absorbance in the 660- to 690-nm range increased, but decreased in the 692- to 715-nm range over time. None of the berries from harvests 1 and 2 were infested with D. suzukii. Twenty percent of harvest 3 and 96% of harvest 4 ‘Chippewa’ berries and 42% of harvest 3 and 100% of the harvest 4 ‘Northblue’ fruit were infested. Thus, mean second derivatives of absorbance of infested fruit were greater than that of uninfested fruit in the 660- to 690-nm range and less in the 692- to 715-nm range. Similarly, mean second derivatives of absorbance in the 660- to 690-nm range of artificially infested berries were greater, whereas those in the 692- to 712-nm range were less than those of berries that were uninfested or poked (Fig. 1B). Although scans of the field-grown and laboratory-infested berries suggested that spectral patterns could be used to discriminate between uninfested and infested fruit, accuracy of one-way blind assays varied from 53% to 71%, whereas error rates varied from 29% to 47% (data not shown), and the proportion of correct true positives was 0.13, whereas that of true negatives was 0.48 (Table 1). The method was better able to predict negatives (specificity) than positives (precision or recall).The inability of the device used in this study to accurately predict positive infestations may be due to its decrease in signal-to noise ratio at about 980 nm. However, data obtained at wavelengths greater than 1000 nm may improve discrimination of infested and uninfested blueberries. Also, improved statistical analysis using partial least squares modeling and the use of machine learning algorithms could improve the predictive ability of spectrometers to detect D. suzuki infestation in berries.We thank Naxo Riera Vila and Lucy DeBoer for technical assistance, James Luby for blueberries, and Geoffrey Harms for designing and fabricating a small fruit adapter for the F-750 spectrometer. Funding was provided by a University of Minnesota College of Food, Agriculture, and Natural Resources Faculty Development Grant and the Minnesota Experiment Station for Project MN21-043.

  PublisherOA PDFDOI

• Spotted-wing Drosophila Host Preference and Quality Vary among Half-high Blueberry Cultivars

  HortScience · 2023-05-12 · 1 citations

  articleOpen accessSenior author

  Spotted-wing drosophila ( Drosophila suzukii ; SWD) is an invasive pest in the United States that is responsible for significant economic damage to soft-skinned fruit and berries worldwide. SWD uses a wide variety of cultivated and wild fruit for reproduction. Host suitability may depend on physical and chemical factors of the fruit, with a positive correlation of SWD oviposition and larval development generally associated with soluble sugar content, softer fruit, and higher pH, and a negative correlation of oviposition with fruit firmness. Variety selection is an important tool for integrated pest management, but few studies have reported host suitability across varieties within a single cultivated crop species for SWD. In this study, we investigated SWD oviposition and larval development in five half-high blueberry cultivars, Chippewa, Northblue, Northland, Patriot, and Polaris, using no-choice and two-choice laboratory bioassays. Using a host potential index, our results showed that Chippewa was the most preferred cultivar for oviposition as measured in the number of eggs laid per fruit, and Polaris was the least preferred. The inverse was true for larval development, with a higher survival rate and adult emergence in ‘Polaris’ than in ‘Chippewa’. There was a negative relationship between fruit firmness and oviposition and a positive correlation between pH and larval development. The results of this study indicate that cultivar selection for half-high blueberries may be a promising integrated pest management (IPM) tool, although further research under field conditions is needed for validation.

  PublisherOA PDFDOI

Frequent coauthors

• Julie Grossman

  University of Minnesota

  8 shared

• S. D. Miller

  Stanford University

  8 shared

• W. D. Hutchison

  7 shared

• Matthew Gullickson

  University of Minnesota

  6 shared

• William T. Stanley

  6 shared

• Rufus Isaacs

  Michigan State University

  5 shared

• Carl J. Rosen

  5 shared

• Ashfaq A. Sial

  5 shared

Education

• M.S./Entomology, Entomology

  University of Minnesota System

  2008

• B.S./Environmental Horticulture, Horticultural Science

  University of Minnesota System

  2003

Awards & honors

• The Annual Distinguished Alumni Award, University of Tenness…
• IPM Team Award, Corteva Agriscience (November 2023)
• Presented to the Sustainable SWD Management Team, presented…
• Distinguished Teaching Award: Undergraduate, UMN CFANS (Apri…
• University of Minnesota Outstanding Community Service Award,…