Research Horticulturist
Jennifer Boldt, Ph.D.
Mailing address: 2801 W. Bancroft St. Mail Stop 604, Toledo, OH 43606
Physical address: 4277A Wolfe Hall, University of Toledo
(330) 439-8776
The Application Technology Research Unit focuses on sustainable production and pest management practices for horticulture crops grown in controlled environments, under the guidance of ARS National Program 305 – Crop Production. Specifically, my research looks at how cultural and environmental factors can be adjusted to improve crop yield, crop quality, and/or resource use efficiency. Current areas of interest include 1) modeling plant growth responses to light, temperature, and carbon dioxide; 2) co-leading Virtual Grower, a decision-support software program that lets users build a virtual greenhouse, estimate heating and lighting costs, and predict crop flowering responses to light and temperature; and 3) evaluating silicon as a beneficial element to reduce crop abiotic and biotic stress in soilless substrates. My team works with ornamental and edible crops produced in greenhouses and indoor warehouses/vertical farms, including bedding plants, herbs, leafy greens, and strawberries.
We currently collaborate with other university researchers on three federally-funded USDA-NIFA-Specialty Crop Research Initiative (SCRI) projects:
- Lighting Approaches to Maximize Profits (LAMP) (Optimizing the cost-effectiveness of lighting in controlled environments, #2018-51181-28365, 2018-2024)
- Optimizing Indoor Agriculture (OptimIA) (Improving the profitability and sustainability of indoor leafy-greens production, #2019-51181-30017, 2019-2024)
- Strawberry Precise Indoor Propagation (Strawberry PIP-CAP SCRI) (Development and integration of next-generation propagation strategies to increase the resilience of the US strawberry supply chain, #2021-51181-35857, 2021-2025)
- Controlled Environment Agriculture Herb Extension and Research Base (CEA HERB) (#2022-51181-38331; 2022-2026)
Research Experience
2013 – 2017 GS-12, Research Horticulturist, USDA-ARS, Toledo, OH
2017 – 2021 GS-13, Research Horticulturist, USDA-ARS, Toledo, OH
2021 – present GS-14, Research Horticulturist, USDA-ARS, Toledo, OH
Educational Background
2013 PhD, Applied Plant Sciences, University of Minnesota
2008 MS, Horticultural Sciences, University of Florida
2005 BS, Environmental Horticulture, University of Florida
2005 BA, Business Administration, University of Florida
- (Clicking on the reprint icon will take you to the publication reprint.)
- Pentas: A data-driven approach for generating leaf tissue nutrient interpretation ranges -(Peer Reviewed Journal)
Veazie, P., Chen, H., Hicks, K., Boldt, J.K., Whipker, B. 2024. Pentas: A data-driven approach for generating leaf tissue nutrient interpretation ranges. Journal of Plant Nutrition. https://doi.org/10.1080/01904167.2024.2405637.
- A sufficiently high blue photon flux density can promote accumulation of phenolic compounds in hydroponic lettuce-(Peer Reviewed Journal)
- Paclobutrazol residues in recirculated water in commercial greenhouses -(Peer Reviewed Journal)
Raudales, R.E., Toro-Herrera, M.A., Fisher, P., Boldt, J.K., Altland, J.E. 2024. Paclobutrazol residues in recirculated water in commercial greenhouses. HortTechnology. 34(2):198-203. https://doi.org/10.21273/HORTTECH05367-23.
- Species survey of leaf hyponasty responses to warming plus elevated CO2 -(Peer Reviewed Journal)
Thomas, M., Roberts, R., Heckathorn, S.A., Boldt, J.K. 2024. Species survey of leaf hyponasty responses to warming plus elevated CO2. Plants. 13(2). Article 204. https://doi.org/10.3390/plants13020204.
- Development of a hydroponic growing protocol for vegetative strawberry production -(Peer Reviewed Journal)
Yafuso, E.J., Boldt, J.K. 2024. Development of a hydroponic growing protocol for vegetative strawberry production. HortScience. 59(3):384–393. https://doi.org/10.21273/HORTSCI17523-23.
- A data-driven approach for generating leaf tissue nutrient interpretation ranges for greenhouse lettuce -(Peer Reviewed Journal)
Veazie, P., Chen, H., Hicks, K., Holley, J., Eylands, N., Mattson, N., Boldt, J.K., Brewer, D., Lopez, R., Whipker, B. 2024. A data-driven approach for generating leaf tissue nutrient interpretation ranges for greenhouse lettuce. HortScience. 59(3):267-277. https://doi.org/10.21273/hortsci17582-23.
- Elevated CO2 increases severity of thermal hyponasty in leaves of tomato -(Peer Reviewed Journal)
Thomas, M.D., Heckathorn, S.A., Boldt, J.K. 2023. Elevated CO2 increases severity of thermal hyponasty in leaves of tomato. Horticulturae. 9:907. https://doi.org/10.3390/ horticulturae9080907.
- Dissolution of silicon from soilless substrates and additives -(Peer Reviewed Journal)
Dey, M.G., Boldt, J.K., Bugbee, B. 2023. Dissolution of silicon from soilless substrates and additives. HortScience. 58(11):1282-1290. https://doi.org/10.21273/HORTSCI17189-23.
- Silicon accumulation by sunflowers at low substrate pH -(Peer Reviewed Journal)
Boldt, J.K., Banks, M.L., Altland, J.E. 2023. Silicon accumulation by sunflowers at low substrate pH. Acta Horticulturae. 1377:739-746. https://doi.org/10.17660/ActaHortic.2023.1377.90.
- The relative sensitivity of marigold vs. tomato to iron (Fe) toxicity is associated with root traits: root-to shoot mass ratio, failure to sequester Fe in roots, and levels of the major Fe-uptake protein, IRT -(Peer Reviewed Journal)
Kostic, E., Heckathorn, S., Bagrowski, T., Franklin, T., Boldt, J.K. 2022. The relative sensitivity of marigold vs. tomato to iron (Fe) toxicity is associated with root traits: root-to shoot mass ratio, failure to sequester Fe in roots, and levels of the major Fe-uptake protein, IRT. Horticulturae. 8(9). Article #803. https://doi.org/10.3390/horticulturae8090803.
- Silicon supplementation induces expression of a histidine-rich defensin gene family in Nicotiana tabacum -(Peer Reviewed Journal)
Muhindi, S., Zellner, W., Flora, C., Boldt, J.K., Leisner, S. 2022. Silicon supplementation induces expression of a histidine-rich defensin gene family in Nicotiana tabacum. Journal of Plant Nutrition. https://doi.org/10.1080/01904167.2022.2108446.
- Photosynthetic responses of greenhouse ornamentals to interaction of irradiance, carbon dioxide concentration, and temperature -(Peer Reviewed Journal)
Atkins, I.K., Boldt, J.K. 2022. Photosynthetic responses of greenhouse ornamentals to interaction of irradiance, carbon dioxide concentration, and temperature. Journal of the American Society for Horticultural Science. 147(2):82-94. https://doi.org/10.21273/JASHS05115-21.
- Using Virtual Grower to model greenhouse energy use-(Trade Journal)
Boldt, J.K., Harbick, K.J., Hegazy, Y.M. 2021. Using Virtual Grower to model greenhouse energy use. Trade Journal Publication. November 2021. p.9-12.
- Comparison of supplemental lighting from high-pressure sodium lamps or light-emitting diodes on morphology and nutrient uptake of greenhouse crops -(Peer Reviewed Journal)
Boldt, J.K., Altland, J.E. 2022. Comparison of supplemental lighting from high-pressure sodium lamps or light-emitting diodes on morphology and nutrient uptake of greenhouse crops. Acta Horticulturae. 1337:313-322. https://doi.org/10.17660/actahortic.2022.1337.42.
- A meta-analysis of the combined effects of elevated carbon dioxide and chronic warming on plant %N, protein content and N-uptake rate -(Peer Reviewed Journal)
Jayawardena, D.M., Heckathorn, S.A., Boldt, J.K. 2021. A meta-analysis of the combined effects of elevated carbon dioxide and chronic warming on plant %N, protein content and N-uptake rate. AoBP (Annals of Botany PLANTS). 13(4). Article plab031. https://doi.org/10.1093/aobpla/plab031.
- Elevated carbon dioxide and chronic warming together decrease nitrogen uptake rate, net translocation, and assimilation in tomato -(Peer Reviewed Journal)
Jayawardena, D.M., Heckathorn, S.A., Rajanayake, K., Boldt, J.K., Isailovic, D. 2021. Elevated carbon dioxide and chronic warming together decrease nitrogen uptake rate, net translocation, and assimilation in tomato. Plants. 10(4):Article 722. https://doi.org/10.3390/plants10040722.
- Lower temperature influences Cauliflower mosaic virus systemic infection -(Peer Reviewed Journal)
Alers-Velazquez, R., Khandekar, S., Muller, C., Boldt, J.K., Leisner, S. 2021. Lower temperature influences Cauliflower mosaic virus systemic infection. Journal of General Plant Pathology. 87:242-248. https://doi.org/10.1007/s10327-021-01003-y.
- Petunia (Petunia ×hybrida) cultivars vary in silicon accumulation and distribution -(Peer Reviewed Journal)
Boldt, J.K., Altland, J.E. 2021. Petunia (Petunia ×hybrida) cultivars vary in silicon accumulation and distribution. HortScience. 56(3):305-312. https://doi.org/10.21273/HORTSCI15486-20.
- Effects of elevated carbon dioxide and chronic warming on nitrogen(N)-uptake rate, -assimilation, and -concentration of wheat -(Peer Reviewed Journal)
Jayawardena, D.M., Heckathorn, S.A., Boldt, J.K. 2020. Effects of elevated carbon dioxide and chronic warming on nitrogen(N)-uptake rate, -assimilation, and -concentration of wheat. Plants. 9(12). Article 1689. https://doi.org/10.3390/plants9121689.
- Cauliflower mosaic virus P6 inclusion body formation: a dynamic and intricate process -(Peer Reviewed Journal)
Velazquez, R.A., Jacques, S., Muller, C., Boldt, J.K., Schoelz, J., Leisner, S. 2020. Cauliflower mosaic virus P6 inclusion body formation: a dynamic and intricate process. Virology. 553:9-22. https://doi.org/10.1016/j.virol.2020.10.003.
- Silicon modulates expression of pathogen defense-related genes during alleviation of copper toxicity in Nicotiana tabacum -(Peer Reviewed Journal)
Flora, C., Khandekar, S., Boldt, J.K., Leisner, S. 2020. Silicon modulates expression of pathogen defense-related genes during alleviation of copper toxicity in Nicotiana tabacum. Journal of Plant Nutrition. 44(5):723-733. https://doi.org/10.1080/01904167.2020.1849296.
- Effect of drought and carbon dioxide on nutrient uptake and levels of nutrient-uptake proteins in roots of barley -(Peer Reviewed Journal)
Bista, D.R., Heckathorn, S.A., Jayawardena, D.M., Boldt, J.K. 2020. Effect of drought and carbon dioxide on nutrient uptake and levels of nutrient-uptake proteins in roots of barley. American Journal of Botany. 107(10):1401-1409. https://doi.org/10.1002/ajb2.1542.
- Blue radiation interacts with green radiation to influence growth and predominantly controls quality attributes of lettuce -(Peer Reviewed Journal)
Meng, Q., Boldt, J.K., Runkle, E.S. 2020. Blue radiation interacts with green radiation to influence growth and predominantly controls quality attributes of lettuce. Journal of the American Society for Horticultural Science. 145(2):75-87. https://doi.org/10.21273/JASHS04759-19.
- Research priorities of the environmental horticultural industry founded through consensus-(Peer Reviewed Journal)
Owen Jr., J.S., Lebude, A.V., Calabro, J., Boldt, J.K., Gray, J., Altland, J.E. 2019. Research priorities of the environmental horticultural industry founded through consensus. Journal of Environmental Horticulture. 37(4):120-126.
- Timing of a short-term reduction in temperature and irradiance affects growth and development of four annual bedding plants -(Peer Reviewed Journal)
Boldt, J.K., Altland, J.E. 2019. Timing of a short-term reduction in temperature and irradiance affects growth and development of four annual bedding plants. Horticulturae. 5(1):15. https://doi.org/10.3390/horticulturae5010015.
- Elevated carbon dioxide plus chronic warming causes dramatic increases in leaf angle in tomato, which correlates with reduced plant growth -(Peer Reviewed Journal)
Jayawardena, D.M., Heckathorn, S.A., Bista, D.R., Boldt, J.K. 2018. Elevated carbon dioxide plus chronic warming causes dramatic increases in leaf angle in tomato, which correlates with reduced plant growth. Plant Cell and Environment. 42(4):1247-1256. https://doi.org/10.1111/pce.13489.
- Comparison of supplemental lighting provided by high-pressure sodium lamps or light-emitting diodes for the propagation and finishing of bedding plants in a commercial greenhouse -(Peer Reviewed Journal)
Craver, J.K., Boldt, J.K., Lopez, R.G. 2019. Comparison of supplemental lighting provided by high-pressure sodium lamps or light-emitting diodes for the propagation and finishing of bedding plants in a commercial greenhouse. HortScience. 54:52-59. https://doi.org/10.21273/HORTSCI13471-18.
- Radiation intensity and quality from sole-source light-emitting diodes affect seedling quality and subsequent flowering of long-day bedding plant species -(Peer Reviewed Journal)
Craver, J.K., Boldt, J.K., Lopez, R.G. 2018. Radiation intensity and quality from sole-source light-emitting diodes affect seedling quality and subsequent flowering of long-day bedding plant species. HortScience. 53:1407-1415. https://doi.org/10.21273/HORTSCI13228-18.
- Silicon alleviates long-term copper toxicity and influences gene expression in Nicotiana tabacum -(Peer Reviewed Journal)
Flora, C.S., Khandekar, S., Boldt, J.K., Leisner, S. 2019. Silicon alleviates long-term copper toxicity and influences gene expression in Nicotiana tabacum. Journal of Plant Nutrition. 42(8):864-878. https://doi.org/10.1080/01904167.2019.1589508.
- Effect of drought on nutrient uptake and the levels of nutrient-uptake proteins in roots of drought-sensitive and –tolerant grasses -(Peer Reviewed Journal)
Bista, D.R., Heckathorn, S.A., Jayawardena, D.M., Mishra, S., Boldt, J.K. 2018. Effect of drought on nutrient uptake and the levels of nutrient-uptake proteins in roots of drought-sensitive and –tolerant grasses. Plants. 7(2):28-44. http://doi:10.3390/plants7020028.
- Influence of substrate physical properties on container weed germination-(Peer Reviewed Journal)
Altland, J.E., Boldt, J.K. 2018. Influence of substrate physical properties on container weed germination. Journal of Environmental Horticulture. 36(1):1-6.
- Silicon accumulation and distribution in petunia and sunflower grown in a rice hull-amended substrate -(Peer Reviewed Journal)
Boldt, J.K., Locke, J.C., Altland, J.E. 2018. Silicon accumulation and distribution in petunia and sunflower grown in a rice hull-amended substrate. HortScience. 53:698-703. https://doi.org/10.21273/HORTSCI12325-17.
- Cultivar variation in silicon accumulation and distribution in Petunia ×hybrida-(Abstract Only)
Boldt, J.K., Altland, J.E. 2017. Cultivar variation in silicon accumulation and distribution in Petunia ×hybrida. HortScience. 52(9):S198.
- Pyrolysis temperature and heating time affect rice hull biochar properties-(Peer Reviewed Journal)
Altland, J.E., Locke, J.C., Boldt, J.K. 2018. Pyrolysis temperature and heating time affect rice hull biochar properties. Acta Horticulturae. 1191:145-152.
- Elevated CO2 plus chronic warming reduces nitrogen uptake and levels or activities of nitrogen -uptake and -assimilatory proteins in tomato roots -(Peer Reviewed Journal)
Jayawardena, D.M., Heckathorn, S.A., Bista, D.R., Mishra, S., Boldt, J.K., Krause, C.R. 2017. Elevated CO2 plus chronic warming reduces nitrogen uptake and levels or activities of nitrogen -uptake and -assimilatory proteins in tomato roots. Physiologia Plantarum. 159:354-365.
- Rice hull mulch affects germination of bittercress and creeping woodsorrel in container plant culture -(Peer Reviewed Journal)
Altland, J.E., Boldt, J.K., Krause, C.R. 2016. Rice hull mulch affects germination of bittercress and creeping woodsorrel in container plant culture. American Journal of Plant Sciences. 7:2359-2375.
- Silicon accumulation and distribution in petunia and sunflower-(Abstract Only)
Boldt, J.K., Locke, J.C., Altland, J.E. 2016. Silicon accumulation and distribution in petunia and sunflower [abstract]. HortScience. 51(9):S368.
- Effect of rice hull mulch on nutrient concentration of fertilized irrigation water-(Abstract Only)
Altland, J.E., Locke, J.C., Boldt, J.K. 2016. Effect of rice hull mulch on nutrient concentration of fertilized irrigation water [abstract]. HortScience. 51(9):S323.
- Granular activated carbon to remove agrichemicals from water-(Trade Journal)
Fisher, P., Grant, G., Zayas, V., Raudales, R., Altland, J.E., Boldt, J.K. 2016. Granular activated carbon to remove agrichemicals from water. Greenhouse Grower Magazine. May/June: 20-22.
- Light intensity and quality from sole-source light-emitting diodes impact growth, morphology, and nutrient content of Brassica microgreens -(Peer Reviewed Journal)
Gerovac, J.R., Craver, J.K., Lopez, R.G., Boldt, J.K. 2016. Light intensity and quality from sole-source light-emitting diodes impact growth, morphology, and nutrient content of Brassica microgreens. HortScience. 51(5):497-503.
- Short-term reductions in irradiance and temperature minimally affect growth and development of five floriculture species-(Peer Reviewed Journal)
Boldt, J.K. 2018. Short-term reductions in irradiance and temperature minimally affect growth and development of five floriculture species. HortScience. 53:1-5.
- Silicon improves flowering characteristics of sunflower and petunia at low phosphorus rates-(Abstract Only)
Boldt, J.K., Altland, J.E., Zellner, W.L., Locke, J.C. 2015. Silicon improves flowering characteristics of sunflower and petunia at low phosphorus rates. HortScience. 50(9):S142.
- Sample container and storage for paclobutrazol monitoring in irrigation water -(Peer Reviewed Journal)
Altland, J.E., Morris, L.A., Boldt, J.K., Fisher, P., Raudales, R. 2016. Sample container and storage for paclobutrazol monitoring in irrigation water. HortTechnology. 25(6):769-773.
- Steel slag raises pH of greenhouse substrates-(Peer Reviewed Journal)
Altland, J.E., Locke, J.C., Zellner, W.L., Boldt, J.K. 2015. Steel slag raises pH of greenhouse substrates. HortScience. 50(4):603-608.
- Has your greenhouse gone virtual?-(Trade Journal)
Boldt, J.K. 2014. Has your greenhouse gone virtual?. Greenhouse Product News. 24(11):36-41.
- A novel approach to reduce greenhouse energy costs-(Trade Journal)
Boldt, J.K. 2014. A novel approach to reduce greenhouse energy costs. Greenhouse Product News. 24(10):14-22.
- Research is our middle name-(Trade Journal)
Boldt, J.K., Altland, J.E., Locke, J.C., Krause, C.R. 2014. Research is our middle name. Greenhouse Product News. 24(7):26-31.
- Current projects of the Application Technology Research Unit (ATRU) USDA-ARS, Wooster/Toledo, Ohio-(Popular Publication)
Krause, C.R., Altland, J.E., Boldt, J.K., Derksen, R.C., Locke, J.C., Ranger, C.M., Reding, M.E., Zhu, H., Zellner, W.L. 2014. Current projects of the Application Technology Research Unit (ATRU) USDA-ARS, Wooster/Toledo, Ohio. The Buckeye. 25(4):18-20.
- Development of photosynthetic response curves and their integration into a decision-support tool for floriculture growers-(Abstract Only)
Boldt, J.K., Erwin, J.E., Fisher, P.R. 2014. Development of photosynthetic response curves and their integration into a decision-support tool for floriculture growers. HortScience. 49(9):S389(Abstract).