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ARS Home » Midwest Area » Wooster, Ohio » Application Technology Research » Research » Research Project #438340
Research Project: Sustainable Production and Pest Management Practices for Nursery, Greenhouse, and Protected Culture Crops

Location: Application Technology Research

2023 Annual Report


Objectives
1: Develop growth models integrating light, temperature, carbon dioxide, and other environmental factors into decision-support software tools to reduce energy costs or increase yield and quality of ornamental and edible crops grown under controlled environment. 2: Develop nutritional and substrate amendment guidelines that improve crop quality and yield or reduce environmental impacts of food and ornamental plants grown in protected horticulture. 3: Develop new hydroponic and container-culture technologies that improve substrate chemical, physical, or biological properties and reduce nutritional, water, and agrichemical inputs. 4: Identify alternative control agents and develop and/or improve methods and strategies for managing pests (insects, other arthropods, and weeds) in horticultural (food and ornamental) crops through improved knowledge of pest biology, ecology, & behavior in order to reduce pesticide usage.


Approach
Ornamental, nursery, and protected culture crops represent about one-fourth of the farm gate value of all specialty crops, and about 15% of the total value of U.S. crop production (USDA NASS Horticultural Crop Census 2014). Production value of nursery and greenhouse crops was estimated at $19 billion in 2013 (USDA NASS Horticultural Crop Census 2014). This project brings together the expertise of USDA-ARS research scientists with cooperators at other universities to focus on ornamental, nursery, and protected culture research. The project is a science-based, outcome-driven, economically motivated program that is already assisting growers in improving the quality of their food and ornamental crops. This project will continue to further our knowledge base in protected culture crops by: 1) integrating light, temperature, carbon dioxide, and other environmental parameters into growth models that enhance decision support in greenhouses and controlled environments, 2) continue developing silicon and other substrate amendments to enhance crop quality and mitigate biotic and abiotic stress, 3) engineering substrates to improve nutrient and water use efficiency, and 4) developing novel management strategies for insects and weeds that integrate knowledge of pest biology with cultural practices and management tools. This project integrates the mission and expertise of the Application Technology Research Unit with other researchers in disciplines critical to the overall success of the project.


Progress Report
In support of Objective 1, Sub-Objective 1A: Research investigating plant responses to environmental conditions continued. We investigated the underlying mechanisms by which the combination of elevated carbon dioxide (CO2) concentration and elevated temperature causes tomato plants to bend their leaves upward. It appears to be partially regulated by auxin signaling and the photoreceptor phytochrome. Sub Objective 1E: Photosynthetic response curves for culinary herbs and leafy greens were added to the software tool PhotoSim. In support of Objective 2, Sub-Objective 2A: Research developing silicon fertilization guidelines for protected horticulture crops continued. Increasing the percentage of rice hulls incorporated into a soilless substrate during propagation (from 0% to 30%) increased foliar accumulation of silicon in strawberry plants. A follow-up study is evaluating the effectiveness of silicon supplementation to control powdery mildew in strawberries. Sub-Objective 2B: The impact of the ammonium: nitrate ratio was evaluated for strawberry stock plant management and daughter plant (asexually produced plants that form on stolons) production. Stolon number and daughter plant quantity increased as the percent nitrogen supplied as nitrate increased from 0% to 80%. Sub-Objective 2C: Data from studies on the carbon source blends and sulfur supplementation impacts on anaerobic soil disinfestation are being analyzed, and manuscripts are in preparation. Experiments on the ability of soilborne plant pathogens to recolonize soils treated with anaerobic soil disinfestation are underway. In support of Objective 3, Sub-Objective 3A: A coarse bark was used to evaluate nitrogen aqueous and gaseous emissions, and ornamental crop growth, when fertilized routinely with water-soluble or controlled-release fertilizer. Coarse bark, and its hydraulic evolution due to roots, continues to be extensively investigated in stratified (i.e., layered) substrate system to increase gas diffusivity in the lower portion of the vertical profile. Iron sulfate amended and unamended coarse bark, within stratified systems, is currently being investigated to determine effect on growth and nutrition of multiple ornamental taxa and subsequent nitrogen and phosphorous runoff and leaching at a micro-nursery scale. Sub-Objective 3B: Extensive on-farm, field trials and controlled studies were conducted to validate the effect of fertilizer placement on crop health and nutrient leaching in a commercial nursery setting. Additional research on practitioner methodology for extracting pore-water when altering fertilizer placement is completed. Sub-Objective 3E: Conventional water quantity and quality data were collected at two Ohio nurseries. Nitrogen, phosphorus, and pesticide concentration and subsequent treatment efficacy was completed in 2022. Refined water treatment coupled with nutrient and pesticide water quality analysis is underway in 2023. Operation water is being collected and data analysis is underway at Ohio, North Carolina, South Carolina, and Michigan industry collaborators to characterize occurrence of non-traditional agrichemicals: per- and polyfluoroalkyl substances (PFAS), microplastics, cyanotoxins, and pesticides. Sub-Objective 3F: Biostimulant experiments for tomato with Fusarium oxysporum f.sp. lycopersici were completed after a delay due to pathogen availability the previous year. Tomato trials with supplemental biological control agents and chitin or chitosan biostimulants are ongoing to determine if addition of beneficial bacteria can enhance disease control. In support of Objective 4, Sub-Objective 4B, Sub-Objective 4B.1: Research was conducted to assess the influence of fireblight (Erwinia amylovora) infection of apple trees on their attractiveness and susceptibility to ambrosia beetles. Fuji and honey crisp apple trees were inoculated with fireblight or non-inoculated and subjected to wild populations of ambrosia beetles. Studies are on-going to determine if the necrotic cankers attract ambrosia beetles as well as induce the production of stress-induced ethanol. A second season of field research was initiated to characterize the seasonal dispersal of ambrosia beetles within ornamental nurseries. An extensive grid of traps was deployed within cooperating ornamental nurseries to understand dispersal patterns and beetle pressure on vulnerable trees within nurseries. These results will also aid in implementing a “push-pull” management tactic, whereby repellents are used to “push” beetles away from valuable crops and attractants are used to “pull” beetles into annihilative traps. Sub-Objective 4B.2: Field research was conducted in spring 2023 to compare the influence of water stress (i.e., flood vs. drought) on the vulnerability of trees to ambrosia beetles. Flood stress, but not drought stress, induced mass attacks by ambrosia beetles on ornamental tree crops. Field experiments were conducted at cooperating commercial nurseries to develop a “push-pull” management strategy to integrate repellents and attractants. Sub-Objective 4B.3: research was conducted to evaluate portable devices for detecting the emission of ethanol from stressed trees. A 3-D printed sensor mounting device was designed and tested for housing a commercially available sensor. Sub-Objective 4B.4: Field research continued to test a proprietary compound as a rescue treatment for disrupting the colonization of vulnerable trees by ambrosia beetles. Following multiple years of field experiments, root drenches with the proprietary compound decreased ambrosia beetle attacks and colonization of the treated trees. Sub-Objective 4B.5: Electroantennography (EAG) and gas chromatography-electroantennographic detection (GC- EAD) were used to characterize the dose response sensitivity of the exotic ambrosia beetle Xylosandrus germanus to acetic acid and ethanol. RNA was extracted from the organ (i.e., mycangium) that ambrosia beetles use to transport spores of their nutritional fungal symbiont. Research indicates that compounds secreted into the mycangium create a selective environment that promotes the division of symbiont spores but inhibits other microorganisms. Sub-objective 4C, Goal 4C.1: We completed 2 years of testing monitoring techniques for red-headed flea beetles but found no suitable monitoring devices and thus were unable to develop a reliable seasonal activity profile. Sub-Objective 4D.1: Research continued to address fungus gnats that negatively affect the production of gourmet oyster mushrooms. Cooperating farmers across the U.S. received and returned sticky traps on a monthly basis to aid in the identification of fungus gnats that infest mushroom farms for comparison with other controlled environment systems. Genetic analyses are being used to identify the fungus gnats collected at cooperating farms across the U.S. Portable techniques were evaluated to reveal the presence of insect infestations of food crops grown within controlled environments. Specifically, herbivore-induced volatiles emitted from tomato plants were detected using a portable gas chromatograph (i.e., z-nose). Environmental DNA deposited on tomato leaves was also collected and evaluated to detect the presence of insect pests. Sub-Objective 4D.2: Research continued to be conducted to evaluate the repellent activity of plant-based essential oils and reduced risk insecticides against fungus gnats that infest oyster mushrooms. Sub-Objective 4E: Quantitative polymerase chain reaction (qPCR) assays were developed for two pathogens, Pseudopyrenochaeta lycopersici and Pseudopyrenochaeta terrestris, that cause tomato corky root rot, a key root- rotting disease in tomato high tunnels. These assays can be used to quantify the pathogen in tomato roots and soil samples, allowing for better diagnosis and tracking of this disease. Sub-Objective 4E2-5: We found that soybeans grown in soil mixed with SlaGemV-1-infected S. sclerotiorum display a resistant phenotype to virus-free pathogenic S. sclerotiorum infection, known as the “biopriming” effect. This phenotype is also coupled with a significant change in differential expression in photochemical genes and disease resistant genes. We transformed the Arabidopsis thaliana plants to express SlaGemV-1. The seeds are at the second generation post transformation (T2) and we will proceed to collect T3 seeds for pathogenicity assay. We also recently published the RNA-Seq analysis determining the differentially expressed genes and ontological pathways of S. sclerotiorum infected with SlaGemV-1. An exceptional amount of differential expression was found. In all, 1,854 genes have been down regulated by virus infection while 1,812 genes have been up regulated by virus infection. In 2022, we divided the proposed target gene for spray induced gene silencing target, fungal Ago2 gene, into 10 segments, and produced in vitro transcripts and performed corresponding pathogenicity assays. Application of dsRNA segments from FF#5~6 significantly suppressed white mold infection. The same regions were cloned and expressed the dsRNA via in vivo from E. coli mutant HT115, using the L4440 plasmid, with two convergent T7 promoter without the T7 terminator. We obtained promising results both from in vitro transcripts and in vivo transcripts extracted by crude preparation.


Accomplishments
1. Virtual Grower energy modeling software physics update and beta launch. Virtual Grower software developed by ARS was updated to version 4 and converted to an online version for more accessibility. The beta test website was launched in May 2023. There are no other software tools available that are specifically targeted at modeling of greenhouse crop harvests and energy consumption, so Virtual Grower addresses those needs. Target users include both growers and researchers. The beta is being tested by cohorts of growers in greenhouse management classes and by selected research colleagues. There are ongoing efforts to improve accuracy of energy and plant growth models which is a direct focus of our research.

2. Silicon induces plant defensins to protect against plant stresses. Plant stress due to pests, diseases, or adverse environmental conditions can negatively impact plant growth and yield. Silicon can help plants tolerate these stresses but the molecular mechanisms underlying this beneficial response are not well understood. ARS researchers in Wooster, Ohio, in collaboration with the University of Toledo, identified histidine-rich defensins that can be upregulated by silicon. These defensins also are involved in reducing disease severity, which shows one potential pathway by which silicon can confer disease suppression in plants. This novel discovery has helped researchers further understand how silicon functions in plants and identified key targets for plant breeders to focus on to increase crop resilience to pathogens.

3. Scent from a parasitic fungus attracts aphid herbivores. The behavioral response of the green peach aphid was characterized in response to the scent emitted from a parasitic fungus (Beauveria bassiana) that infects and kills its insect host. ARS researchers in Wooster, Ohio, demonstrated that volatiles emitted from the parasitic fungus Beauveria bassiana attract rather than repel aphids. Attraction to the parasitic fungus will result in increased infection since direct contact is required. These results will aid researchers in developing an attract-and-kill strategy using parasitic, entomopathogenic fungi as microbial control agents to reduce the reliance on conventional insecticides.

4. Developed an effective biopesticide for Sclerotinia sclerotiorum. Sclerotinia sclerotiorum is a serious issue in high tunnel tomato production and causes important disease of multiple crops in the north central USA. Control methods based on natural host resistance or fungicides have not provided sufficient control to date. Fungal viruses that infect S. sclerotiorum and weaken the ability of the fungus to grow or to infect plants could contribute to control of the disease. ARS researchers in Wooster, Ohio, have developed an effective biopesticide from crude viral particle preparation as fungicide spray. Growers can also adapt the technology to simultaneously control Botrytis cinerea in the greenhouse due to the mycovirus also reduces the pathogenicity of other Sclerotiniaceae fungi.

5. New tool to track a hidden tomato disease that can reduce yield by 50 percent if not detected. Tomato corky root rot is a root disease that can half tomato yield and is found in 50% of tomato high tunnels. This disease often hides from growers and researchers until it is too late because it attacks roots, is slow growing and is difficult to isolate from plants, so improved methods to detect this disease are needed. ARS researchers in Wooster, Ohio, developed a quantitative polymerase assay (qPCR) to rapidly detect corky root rot pathogens in roots and soils. This assay provides a tool for researchers to rapidly detect and track the pathogens in order to provide farmers with strategies to better manage this disease.


Review Publications
Ammons, A., LeBude, A.V., Owen Jr, J.S., McGinnis, M. 2022. Effect of irrigation, fertilizer rate and placement, and two substrates on growth of rose and hydrangea. Journal of Environmental Horticulture. 40(3):123-128. https://doi.org/10.24266/2573-5586-40.3.123.
 Testen, A.L., Shaw, R.S., Rotondo, F., Moodispaw, M., Miller, S.A. 2023. A quantitative PCR method to detect the tomato corky root rot pathogens, Pseudopyrenochaeta lycopersici and Pseudopyrenochaeta terrestris. Plant Disease. https://doi.org/10.1094/PDIS-08-22-2009-RE.
 Rotondo, F., Khatri, N., Testen, A.L., Miller, S.A. 2023. Evaluation of a proprietary plant extract to suppress bacterial canker and improve yield in hydroponic tomatoes. Plant Health Progress. https://doi.org/10.1094/PHP-10-22-0112-RS.
 Pedersen, C.J., Marzano, S.L. 2022. Characterization of transcriptional responses to genomovirus infection of the white mold fungus, Sclerotinia sclerotiorum. Viruses. 14(9). Article #1892. https://doi.org/10.3390/v14091892.
 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.
 Criscione, K.S., Fields, J.S., Owen Jr, J.S. 2022. Root exploration, initial moisture conditions, and irrigation scheduling influence hydration of stratified and non-stratified substrates. Horticulturae. 8(9). Article #826. https://doi.org/10.3390/horticulturae8090826.
 Cavaletto, G., Ranger, C.M., Reding, M.E., Montecchio, L., Rassati, D. 2022. Species-specific effects of ethanol concentration on host colonization by four common species of ambrosia beetles. Journal of Pest Science. 96:833-843. https://doi.org/10.1007/s10340-022-01537-w.
 Dzurenko, M., Kulfan, J., Galko, J., Holec, J., Saniga, M., Zubrik, M., Ranger, C.M., Zach, P. 2021. Can the non-native ambrosia beetle Xylosandrus germanus withstand an unusually cold winter in the West Carpathian forest in Central Europe? Folia Oecologica. 49(1):1-8. https://doi.org/10.2478/foecol-2022-0001.
 Gugliuzzo, A., Kreuzwieser, J., Ranger, C.M., Tropea Garzia, G., Biondi, A., Biedermann, P.H. 2023. Volatiles of fungal cultivars act as cues for host-selection in the fungus-farming ambrosia beetle Xylosandrus germanus. Frontiers in Microbiology. 14. Article #1151078. https://doi.org/10.3389/fmicb.2023.1151078.
 Sutherland, R., Meurisse, N., Pugh, A., Ranger, C.M., Reding, M.E., Kerr, J., Russell, J., Withers, T. 2023. Phenological observations and trapping tactics for the granulate ambrosia beetle Xylosandrus crassiusculus (Coleoptera: Curculionidae, Scolytinae) in New Zealand. Agricultural and Forest Entomology. 25(3): 355-364. https://doi.org/10.1111/afe.12558.
 Geedi, R., Canas, L., Reding, M.E., Ranger, C.M. 2022. Attraction of Myzus persicae (Hemiptera: Aphididae) to volatiles emitted from the entomopathogenic fungus Beauveria bassiana. Environmental Entomology. 52(1):31-38. https://doi.org/10.1093/ee/nvac100.
 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.