Final report for GNE24-336
Project Information
This project evaluated the efficacy of the biological control agent LifeGard (Bacillus mycoides isolate J, BmJ) for managing downy mildew (Plasmopara viticola) in 'Chardonnay' grapevines. Through a field experiment conducted at Cornell University's AgriTech research station in Geneva, New York, during the 2024 growing season, the effects of BmJ alone and in combination with fungicides on disease incidence, vine physiology, and fruit quality were evaluated. Four treatments were compared: conventional fungicides, BmJ rotated with fungicides, BmJ rotated with another biocontrol (NatBio), and an untreated control. Results demonstrated that BmJ, when alternated with synthetic fungicides, achieved disease control equivalent to conventional fungicide-only treatment, reducing disease severity by approximately 89% compared to untreated controls. Rotation with biocontrol alone (BmJ + NatBio) provided intermediate disease control (73% reduction). All treatments maintained leaf chlorophyll content and increased cluster weight by 144-179% compared to controls. Metabolomic profiling revealed that treated plants showed lower abundance of stress-related metabolites while maintaining defense-related compounds. An unexpected finding was that biocontrol-only approaches were insufficient under high disease pressure conditions experienced in 2024. While these findings are based on a single-year, single-site study, they provide preliminary evidence supporting the integration of BmJ into vineyard IPM programs as a sustainable approach to reducing dependence on synthetic fungicides while maintaining productivity. Multi-year and multi-site trials are recommended to validate these results.
Objective 1: To evaluate the efficacy of the biocontrol agent LifeGard (BmJ), used in an integrated approach with conventional and reduced fungicide applications, for managing downy mildew in vineyards and the resulting physiological response in the plants.
Specific objectives:
- To assess the disease pressure of downy mildew by evaluating incidence and severity on grapevines throughout the growing season.
- To determine the physiological response by measuring chlorophyll and nitrogen content in leaves (via SPAD) and Brix, pH, and titratable acidity in berries at harvest.
- To evaluate yield parameters, including cluster weight, berry weight, and overall cluster disease at harvest.
Objective 2: To investigate the impact of applying the biocontrol agent LifeGard on the metabolic profile of susceptible grapevine cultivars grown in field conditions and explore the relation of these metabolic alterations to improved resistance against downy mildew infections.
Specific objectives:
- To determine the presence and changes in abundance of resistance-related metabolites, including defense-related compounds such as phytoalexins (stilbenes), flavonoids, and phenolic compounds, through untargeted metabolomic profiling.
- To determine the metabolites related to plant stress by evaluating the influence of biocontrol application on the production of stress-associated metabolites, including organic acids and amino acid derivatives, compared to untreated controls.
Downy mildew, caused by the obligate biotrophic oomycete Plasmopara viticola, represents one of the most economically significant diseases affecting grapevines in the Northeastern United States (Hed, 2018; Koledenkova et al., 2022). The environmental conditions characteristic of this region—cool temperatures, high humidity, and variable weather patterns—create ideal conditions for disease development throughout the growing season. In susceptible cultivars, downy mildew can cause 75-100% leaf loss, leading to substantial yield reductions or complete crop failure (Koledenkova et al., 2022; Sharma et al., 2023). The pathogen infects all green tissues, including leaves, young stems, and berries, causing leaf necrosis, premature defoliation, shoot distortion, and reduced fruit quality. Beyond direct yield losses, infection impairs photosynthetic rates and alters berry composition, directly influencing the flavor and quality of wine produced from affected grapes (Besrukow et al., 2024; Moriondo et al., 2005).
Growers in the Northeast have consistently identified mildew diseases as the most significant threat to their vineyards. Economically important susceptible cultivars in the region include 'Chardonnay,' 'Chancellor,' and various Vitis vinifera hybrids. The management of downy mildew has traditionally depended on intensive synthetic fungicide spray programs, with applications occurring every 7-14 days throughout the growing season (Campbell et al., 2021; Gold, 2023). This heavy reliance on fungicides has raised significant sustainability concerns. The overuse of synthetic chemicals has contributed to the development of fungicide resistance, particularly to quinone outside inhibitors (QoI) and carboxylic acid amide (CAA) fungicide groups, with resistance prevalence increasing across the region (Baudoin et al., 2008; Sharma et al., 2025). Additionally, environmental concerns regarding fungicide runoff, leaching into water bodies, and spray drift have intensified (Damalas & Eleftherohorinos, 2011; Geiger et al., 2010). Rising production costs associated with frequent applications, combined with changing consumer preferences for sustainably produced agricultural products and evolving government regulations, have created an urgent need for alternative disease management strategies.
Biological control agents (BCAs) have emerged as a promising component of integrated pest management (IPM) programs, offering the potential to reduce synthetic fungicide inputs while maintaining effective disease control (Pertot et al., 2017; Raymaekers et al., 2020). Among the diverse BCAs studied, bacteria from the genus Bacillus are particularly valued for their capacity to enhance plant defense responses through induced systemic resistance (ISR) (Kloepper et al., 2004; Li et al., 2019). Bacillus mycoides isolate J (BmJ), the active ingredient in the commercial product LifeGard, has demonstrated efficacy in suppressing diseases across multiple cropping systems, including cercospora leaf spot in sugar beets, botrytis in tomatoes and ornamentals, halo blight in hops, and anthracnose in cucumbers (Bargabus et al., 2002; Jacobsen et al., 2004; Neher et al., 2009; Hatlen et al., 2022). Research has shown that BmJ increases pathogenesis-related proteins, including chitinase, β-1,3-glucanase, and peroxidase activity, priming plant defenses against subsequent pathogen attack (Bargabus et al., 2002; Neher et al., 2009).
However, despite promising results in other crops, there was limited research evaluating BmJ performance specifically in vineyards, particularly in the Northeastern United States and on highly downy mildew susceptible cultivars such as 'Chardonnay.' Previous studies suggested that BmJ performs best when applied as part of a rotation spray program rather than as a standalone treatment (Mairs, 2018; Shrestha & Hausbeck, 2021), but the optimal integration strategies within existing vineyard disease management programs remained understudied. Additionally, there was a lack of data on the physiological effects of BmJ on photosynthetic function, yield parameters, and biochemical defense responses in grapevines under field conditions.
This project addressed these knowledge gaps by conducting a comprehensive field evaluation of BmJ in 'Chardonnay' grapevines under natural disease pressure conditions. The research assessed BmJ efficacy in two integrated application programs (rotation with fungicides and biocontrol-only rotation), measured effects on disease control, vine physiology, yield, and fruit quality, and employed untargeted metabolomics to investigate the biochemical mechanisms underlying treatment responses. The findings from this research provide evidence-based recommendations for grape growers in the Northeast seeking to integrate biocontrol agents into their disease management programs, contributing to more sustainable viticulture practices while maintaining the productivity and profitability essential for the region's wine industry.
Cooperators
- (Educator and Researcher)
- (Researcher)
- (Educator and Researcher)
Research
Experimental Design
This field experiment was conducted during the 2024 growing season at Cornell University's AgriTech research station in Geneva, New York, using 38-year-old Vitis vinifera 'Chardonnay' grapevines. The vines were trained to a mid-wire cordon system with vertical shoot positioning. Spacing was 1.8 m between vines within the row and 2.7 m between rows. Vines were maintained without irrigation and received standard canopy management, fertilization, weed control, and insecticide applications consistent with commercial vineyard practices in the region.
The experimental design followed a randomized complete block design (RCBD) consisting of four fungicide treatment programs and four blocks. Treatments were arranged within six consecutive vineyard rows, where each plot (experimental unit) consisted of four adjacent grapevines. Within each panel, the two central vines were used for data collection to minimize edge effects and potential spray drift interference.
Treatments
The four treatment programs were:
- Conventional fungicide program (P1-F): Standard fungicide rotation modeled after protocols from the Gold Lab pesticide trials, including products such as Manzate Max, Aliette, Zampro, Ranman + Phostrol, and Theia.
- BmJ + Fungicides (LG+P2-F): Rotation of LifeGard WG (BmJ) alternated with synthetic fungicides including Kocide 2000 (copper hydroxide), Zampro, and Ranman. BmJ was applied 2 times during the season.
- Biocontrol only (LG+NB): Rotation of LifeGard WG (BmJ) alternated with Nat Bio Liquid (an unregistered biopesticide containing a microbial active ingredient). BmJ was applied 3 times during the season.
- Untreated control (UTC): No fungicide or biocontrol applications for downy mildew.
Fungicide treatments were generally applied every 12-14 days using a hooded boom sprayer operating at 100 psi, delivering 50 gallons per acre (GPA) pre-bloom and 100 GPA post-bloom. This was applied by the farm technician in the Gold Lab (Cornell Agritech). In addition to the experimental treatments, standard sprays targeting powdery mildew (Erysiphe necator), Phomopsis (Diaporthe ampelina), and insect pests including grape berry moth (Paralobesia viteana), grape phylloxera (Daktulosphaira vitifoliae), and Japanese beetle (Popillia japonica) were applied uniformly across all plots during the season.
Downy Mildew Disease Assessment
Downy mildew (Plasmopara viticola) severity and incidence were visually assessed every 7-10 days between July 2nd and October 3rd, covering the main period of disease development during the growing season. For each experimental unit, 30 leaves were assessed from the two center vines. Disease severity was estimated as the percentage of the leaf surface affected on each side independently, using a visual reference scale from Scapin Buffara et al. (2014) to standardize severity estimates across observations. Disease incidence was calculated as the proportion of symptomatic leaves (those showing visible symptoms or sporulation) among the 30 leaves assessed per replicate. Both the adaxial (top) and abaxial (bottom) surfaces of each leaf were examined separately. The abaxial surface was inspected for active sporulation and necrotic tissue, while the adaxial surface was evaluated for oil spots and necrosis.
Relative Leaf Chlorophyll and Nitrogen Assessment
Relative chlorophyll and nitrogen content in grapevine leaves were assessed throughout the growing season using a portable chlorophyll meter (GOYOJO GYJ-C Chlorophyll Meter, China). Measurements were conducted every 7-10 days from July 2nd to October 3rd, 2024. For each experimental unit, 24 leaves were randomly selected—12 from each side of the canopy—using the two central vines within each four-vine panel to minimize edge effects. Selected leaves were fully expanded, exposed to sunlight, and chosen from lateral shoots to ensure consistency in developmental stage and light exposure across samples. Only visually healthy, non-infected tissue was used for measurements. In cases where localized symptoms of disease were present on a selected leaf, measurements were taken exclusively from unaffected, healthy tissue to maintain data accuracy and reliability.
Yield Components and Fruit Chemistry Analysis
Grapes were harvested on September 19th; the date of harvest was determined based on fruit ripening parameters (Brix, pH, titratable acidity). At harvest, 20 grape clusters were randomly selected from the two central vines of each experimental unit, collected, and weighed using a hanging scale. The average cluster weight was calculated by dividing the total weight by the number of clusters (Harner et al., 2024).
To prepare a representative subsample for fruit chemical analysis, portions were cut from multiple clusters and placed into clean, 1-gallon Ziplock bags. Each bag was labeled and immediately placed in a cooler with ice, then transferred to a -20°C freezer for long-term storage until processing.
For berry weight assessment, 200 berries were randomly selected and weighed from each sample. Berries were thawed overnight (~12 hours), blended until homogeneous, and heated in a water bath at 60°C for one hour to dissolve tartrate crystals. Juice was filtered using vacuum filtration with cheesecloth-lined flasks and allowed to cool to room temperature (20–22°C) prior to analysis.
Brix readings were obtained by placing 1 mL of juice onto a handheld refractometer and recording the value at the blue demarcation line. pH was measured using a calibrated pH meter. Titratable acidity (TA) was determined via titration with freshly prepared 0.1 M NaOH using a Mettler Toledo G20 Compact Titrator system. TA values were expressed as grams of tartaric acid per liter of juice (g/L).
Overall Cluster Disease Rating
At harvest, overall disease severity on grape clusters was assessed visually on 10 random clusters per replicate on the same vines used for other data collection (Hed & Centinari, 2018). Each cluster was examined for disease symptoms, including visible lesions, rots, and other signs of pathogen infection. Severity was rated as the estimated percentage of the cluster surface exhibiting symptoms.
Metabolomic Sampling and Analysis
Leaf samples for metabolomic analysis were collected at four time points relative to the second BmJ application (July 23rd): 24 hours before treatment (July 22), 24 hours after treatment (July 24), 72 hours after (July 26), and 144 hours after (July 29). Sampling was conducted across all treatments using the two central vines of each experimental unit. For each experimental unit, six fully expanded, tender, and green leaves were randomly selected, with three leaves collected from each side of the canopy (Avesani et al., 2023). From each leaf, five discs were punched using a sterile puncher, resulting in a total of 30 leaf discs per sample (approximately 80-100 mg fresh weight). Samples were immediately flash-frozen in liquid nitrogen, stored on dry ice during collection, and transferred to a -80°C freezer for long-term storage. Punchers were disinfected with 70% ethanol and thoroughly dried between samples to prevent cross-contamination.
Metabolite Extraction: Plant tissue samples were homogenized using a mortar and pestle in liquid nitrogen and transferred into 2.0 mL microcentrifuge tubes. A cooled extraction solution consisting of methanol:water:formic acid (80:20:0.05, v/v/v) supplemented with 1 µM chlorpropamide (internal standard) was added (1.0 mL per sample). Samples were sonicated for 5 min and centrifuged at >15,000 × g for 5 min at 4°C. A second extraction was performed on the pellet. Supernatants from both extractions were pooled, evaporated to dryness using a nitrogen dryer, and stored at −80°C until analysis.
LC-MS Analysis: Ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-TOF-MS) analysis was performed at the Penn State Metabolomics Core Facility using a Nexera 40 HPLC system (Shimadzu) coupled to a ZenoTOF 7600 mass spectrometer (Sciex). Electrospray ionization (ESI) was employed in both positive (ESI+) and negative (ESI−) ion modes. Chromatographic separation was achieved using a Merck SeQuant ZIC-cHILIC column (2.1 × 150 mm, 3.0 µm particle size) maintained at 30°C.
Data Processing: Raw LC-MS data were processed using MS-DIAL software (version 5.5.250627) with ESI(+) and ESI(−) MS/MS spectral libraries. Putative metabolite identification was performed using MS-DIAL's spectral library matching against public databases, considering both accurate mass (m/z) and MS² fragmentation patterns. Annotated metabolites were classified into chemical classes using the ClassyFire web-based application.
Statistical Analysis
All statistical analyses were performed using R version 4.3.3, with the exception of the metabolomics data, which were analyzed using MetaboAnalyst 6.0. Disease severity and incidence data were used to calculate the area under the disease progress curve (AUDPC) for each treatment using the trapezoidal method (Madden et al., 2017). Data were tested for normality using the Shapiro–Wilk test (α = 0.05), and appropriate transformations were applied when necessary. Treatment effects were assessed using one-way ANOVA, with post hoc comparisons conducted using Fisher's LSD or Tukey's HSD test. All statistical tests were conducted at a significance level of α = 0.05.
For metabolomic data, preprocessing consisted of normalization by reference feature (chlorpropamide), relative standard deviation (RSD) filtering, log₁₀ transformation, and Pareto scaling. Partial least squares discriminant analysis (PLS-DA) was performed to identify metabolic features that differentiate treatment groups. Model quality was assessed using R² and Q² parameters, and permutation testing (n=1000 permutations) was performed to validate model significance. Variable importance in projection (VIP) scores were calculated to identify metabolites contributing most to group discrimination (VIP > 1.0).
Downy Mildew Disease Control
All treatments exhibited significantly lower downy mildew severity compared to the untreated control (P < 0.05). BmJ + Fungicides (LG+P2-F) and Fungicides only (P1-F) achieved the highest disease severity reduction at 89.95% and 88.78%, respectively. The biocontrol-only treatment (LG+NB) was less effective, achieving 72.92% reduction. Similarly, LG+P2-F and P1-F reduced disease incidence by approximately 59%, while LG+NB showed only 23.69% reduction and did not differ significantly from UTC for incidence.
By late August, mean severity on UTC vines exceeded 85%, reaching 100% incidence by late July. In contrast, P1-F and LG+P2-F maintained severity below 16% and incidence below 50% until early September. These results demonstrate that BmJ rotation with synthetic fungicides can achieve disease control equivalent to conventional programs, consistent with previous findings in grapevines (Mairs, 2018; Gold, 2023). The intermediate performance of LG+NB suggests that biocontrol-only approaches may be insufficient under high disease pressure, aligning with observations by Shrestha & Hausbeck (2021) in geranium.
Leaf Chlorophyll and Nitrogen Content
All treated vines maintained similar SPAD values for chlorophyll and nitrogen content throughout the season, with no significant differences among P1-F, LG+P2-F, and LG+NB. UTC vines showed a sharp mid-season decline starting in early August, reflecting severe disease pressure that left minimal uninfected tissue available for sampling. These findings indicate that maintaining disease severity below approximately 27% (the highest level in LG+NB) preserves leaf physiological function in 'Chardonnay' grapevines, supporting vine health and photosynthetic capacity regardless of treatment type.
Cluster Weight and Overall Cluster Disease
Cluster weight was significantly higher in all treated vines compared to UTC, with no significant differences among treatments. UTC produced the lowest average cluster weight (38.5 g), while LG+P2-F (107.5 g), P1-F (99 g), and LG+NB (94 g) showed increases of 179%, 157%, and 144%, respectively. Overall cluster disease severity at harvest was highest in UTC (70.9%), with all treatments achieving 68-79% reduction and no significant differences among them. These results suggest that BmJ, when combined with either synthetic fungicides or biocontrol partners, maintains yield parameters comparable to conventional programs, consistent with Mairs (2018).
Fruit Chemistry
Total soluble solids (Brix) did not differ significantly among treatments (19.83-21.18°Brix), suggesting sugar accumulation is less sensitive to disease-induced stress than other parameters. However, pH and titratable acidity (TA) showed significant differences. UTC had higher pH (3.68) and TA (11.57 g/L) compared to P1-F and LG+P2-F (pH: 3.57-3.62; TA: 9.5-9.98 g/L). LG+NB showed intermediate TA values. Berry weight increased by 11.7% in P1-F and LG+P2-F compared to UTC. For 'Chardonnay' wine production, these pH and TA differences are meaningful, as UTC fruit would produce lower quality wine due to chemical imbalances and disease-related damage.
Metabolomic Profiling
PLS-DA analysis revealed temporal patterns in metabolic separation between treatments. At 24 hours before application (-24h), metabolite profiles overlapped across all treatments, confirming no pre-existing differences. Maximum separation occurred at 24h post-application in ESI+ mode, with treated groups clustering distinctly from UTC. This separation persisted through 72h before partial convergence by 144h. Notably, LG+P2-F samples clustered metabolically with P1-F at most timepoints, while LG+NB exhibited an intermediate position closer to UTC.
Among endogenous plant metabolites, stress-associated compounds (beta-hydroxy acids, organic acids, amino acid derivatives including tryptophan) showed 1.8-3.0-fold higher abundance in UTC compared to treated plants at 24h and 72h post-application, indicating metabolic perturbation from disease pressure. Defense-associated metabolites, including stilbenes, flavonoids, and phenolic compounds, showed moderately higher abundance in treated plants. Flavonoid detection peaked at 24h post-application, coinciding with maximum treatment discrimination, while stilbenes were consistently detected across all timepoints but showed higher abundance in UTC, suggesting sustained stress response in untreated vines.
These metabolomic findings support the hypothesis that treated plants show decreased abundance of stress-related metabolites while maintaining defense-related compounds. The clustering of LG+P2-F with P1-F suggests similar effects on host defense activation despite different active ingredients, potentially reflecting complementary modes of action where fungicides provide direct pathogen suppression while BmJ induces plant resistance mechanisms (Bargabus et al., 2002). The intermediate metabolic position of LG+NB is consistent with its reduced disease control efficacy.
Unexpected Findings and Limitations
An unexpected finding was that the biocontrol-only approach (LG+NB), while significantly better than no treatment, was insufficient under the high disease pressure experienced in 2024. This suggests BmJ is most effective when combined with direct-acting fungicides rather than used as a standalone strategy, particularly in susceptible cultivars under conducive environmental conditions.
These findings must be interpreted within the context of experimental limitations. This was a one-year, single-site study using one cultivar ('Chardonnay'). The study did not include a BmJ-only treatment, preventing direct assessment of BmJ standalone efficacy. Additionally, P1-F and LG+P2-F used different fungicide rotations, precluding perfectly controlled comparisons. Multi-year and multi-site trials are recommended to validate these results across varying disease pressure and climatic conditions.
This project sought to evaluate the efficacy of the biocontrol agent LifeGard (Bacillus mycoides isolate J, BmJ) for managing downy mildew in 'Chardonnay' grapevines and to investigate the metabolic mechanisms underlying treatment effects. Specifically, we aimed to: (1) assess BmJ efficacy in integrated spray programs for disease control, vine physiology, and fruit quality; and (2) characterize metabolic changes in grapevine leaves following BmJ application through untargeted metabolomics.
Objective 1 was successfully met. BmJ rotated with fungicides achieved disease control equivalent to the conventional fungicide program, with both treatments reducing severity by approximately 89% compared to untreated controls. The biocontrol-only rotation provided intermediate but significant control (73% reduction). All treatments maintained leaf chlorophyll and nitrogen content, while UTC showed sharp physiological decline. Cluster weight increased by 144-179% in treated vines compared to controls, with no significant differences among treatments. Fruit chemistry parameters (pH, titratable acidity) were significantly improved in fungicide-integrated treatments compared to UTC.
Objective 2 was partially met. Metabolomic analysis revealed that treated plants showed lower abundance of stress-related metabolites (organic acids, amino acids) and maintained defense-associated compounds (stilbenes, flavonoids) compared to UTC. LG+P2-F metabolite profiles clustered with P1-F, suggesting similar defense activation mechanisms despite different active ingredients. However, due to limited sample size (n=4 per treatment) and the exploratory nature of untargeted metabolomics, these findings should be considered preliminary and require further validation.
These results demonstrate that BmJ can be successfully integrated into vineyard IPM programs for highly susceptible cultivars under high disease pressure conditions. For cooperating growers, this translates to potential practical benefits: replacing 2-3 synthetic fungicide applications per season with BmJ applications while maintaining equivalent disease control and yield. This could reduce input costs associated with synthetic fungicides and address resistance management concerns, as BmJ provides a different mode of action (induced resistance) that does not contribute to selection pressure for fungicide-resistant pathogen populations.
An important limitation is that this was a one-year, single-site study. The biocontrol-only approach was insufficient under 2024's high disease pressure, indicating that BmJ should be used in rotation with fungicides rather than as a standalone treatment in susceptible cultivars. Environmental conditions vary annually, and BmJ efficacy may differ under lower disease pressure years.
In conclusion, this research provides evidence-based support for integrating BmJ into vineyard disease management programs in the Northeastern United States. The findings contribute to sustainable viticulture practices by offering growers a viable strategy to reduce synthetic fungicide reliance while maintaining productivity and fruit quality essential for the region's wine industry.
Education & outreach activities and participation summary
Participation summary:
This project focused on the New York and Pennsylvania grape-growing community, a cornerstone of the agricultural landscape within the Northeast USA. These growers cultivate a variety of grape cultivars for wine, juice, and table consumption (Fontaine et al., 2021; Gardner et al., 2018). One of their primary needs, identified through industry reports, grower surveys, and extension workshops, is to reduce reliance on fungicides (Campbell et al., 2021). Concerns encompass the emergence of fungicide resistance, potential environmental consequences of overuse, and rising production costs (Damalas & Eleftherohorinos, 2011). Additionally, there is a growing market demand for sustainable practices in agriculture, driven by consumer preferences and environmental considerations.
Research findings were shared with the scientific community and grape growers through multiple channels. I presented a poster at the American Phytopathological Society (APS) Plant Health 2025 conference, where I shared key results from this research with plant pathologists, extension specialists, and industry representatives. This presentation facilitated discussions on biocontrol integration strategies and gathered valuable feedback from researchers working on similar disease management challenges.
Additionally, I delivered a public seminar talk about my thesis research, of which this SARE project is a core component. This seminar was open to the public and provided an opportunity to communicate findings directly to students, faculty, extension educators, and interested community members in an accessible format.
This research forms a central chapter of my thesis, which will become publicly available through the Penn State graduate school repository upon acceptance. This ensures long-term accessibility of the complete methodology, results, and discussion for future researchers and practitioners seeking detailed information on biocontrol integration in vineyards.
Furthermore, a peer-reviewed manuscript is currently in preparation based on this work. Publication in a scientific journal will contribute to the broader knowledge base on biocontrol efficacy and metabolic defense mechanisms in grapevines, providing validated evidence that extension educators and growers can reference when making disease management decisions.
Collaboration with Cornell University's Gold Lab in Geneva, New York, was essential to this project's success. The Gold Lab works with a large network of growers, and through this collaboration, research findings can reach a wide audience of Northeastern grape producers. Future outreach efforts will include publishing extension articles through Penn State Extension (Hed, 2018), which is widely read by farmers in the Northeast, providing clear and practical guidance on incorporating biocontrol agents into vineyard management practices.
Overall, this project recognizes the importance of not only conducting rigorous scientific research but also effectively communicating findings to grape growers. By actively engaging with the industry through conferences, seminars, publications, and extension partnerships, this research contributes to the advancement of sustainable viticulture practices while addressing grower needs and promoting environmentally responsible grape production.
Project Outcomes
This project contributes to agricultural sustainability by providing evidence that biocontrol agents can be integrated into vineyard disease management programs without sacrificing efficacy. The research demonstrated that rotating BmJ with synthetic fungicides achieved equivalent disease control to conventional programs, offering growers a pathway to reduce synthetic chemical inputs while maintaining productivity.
Economic benefits: Growers adopting this integrated approach could potentially replace 2-3 synthetic fungicide applications per season with BmJ, reducing input costs. Additionally, maintaining fruit quality parameters (pH, titratable acidity) supports wine quality and market value.
Environmental benefits: Reduced synthetic fungicide applications decrease chemical runoff, leaching into water bodies, and spray drift. Integrating biocontrols also addresses fungicide resistance management by introducing a different mode of action (induced resistance) that does not contribute to selection pressure on pathogen populations.
Social benefits: This research supports grower adoption of sustainable practices aligned with growing consumer demand for environmentally conscious products, potentially improving market access and public perception of the wine industry.
Basis for numbers: Approximately 100 people were reached through my APS Plant Health 2025 poster presentation and public thesis seminar. New collaborations were established with Cornell University's Gold Lab and Michigan State University's Miles Lab. No practice changes have been documented yet, as dissemination is ongoing and the thesis/manuscript are still in preparation.
This project significantly enhanced my knowledge and skills in sustainable agriculture, particularly in integrated pest management strategies for perennial crops. I gained hands-on experience in field trial design, disease assessment methodologies, plant physiological measurements, and fruit chemistry analysis. Most notably, I developed expertise in untargeted metabolomics, including sample collection, LC-MS analysis, and multivariate statistical approaches, which provided insights into the biochemical mechanisms underlying biocontrol efficacy.
My understanding of biocontrol agents deepened considerably. I learned that BmJ works best as part of an integrated program rather than a standalone treatment, and that its efficacy depends on disease pressure and environmental conditions. This nuanced understanding of biocontrol limitations and optimal application strategies will inform my future recommendations to growers.
I plan to continue research in sustainable plant disease management, focusing on integrating biological control agents into IPM programs for specialty crops. I aim to pursue a career combining research and extension, translating scientific findings into practical recommendations for growers. Potential future research includes multi-year validation trials, evaluation across different cultivars and regions, and deeper investigation of defense-related metabolic pathways.
Finally, this project produced one thesis chapter (publicly available upon graduation), one poster presentation at APS Plant Health 2025, one public seminar, and one peer-reviewed manuscript currently in preparation. These outputs contribute to the scientific knowledge base on biocontrol integration in vineyards and provide evidence-based guidance for sustainable viticulture practices.
The randomized complete block design with four replicates provided robust statistical power for disease and yield assessments. Collaboration with Cornell University's Gold Lab was essential to the project's success, providing access to established vineyard infrastructure, spray equipment, and expertise in grapevine pathology. Combining traditional disease assessments with untargeted metabolomics offered mechanistic insights beyond efficacy data alone, allowing us to explore the biochemical basis of treatment effects.
However, several challenges limited the scope of conclusions. The single-year, single-site design restricts generalizability across different environmental conditions and disease pressure levels. The high disease pressure experienced in 2024 may have masked potential benefits of biocontrol-only approaches that could perform adequately under moderate conditions. Additionally, the lack of a BmJ-only treatment prevented direct assessment of standalone efficacy independent of rotation partners.
Key lessons learned include that BmJ should be evaluated within integrated programs rather than as a complete replacement for fungicides, particularly in highly susceptible cultivars like 'Chardonnay.' Metabolomics, while informative, requires larger sample sizes for definitive conclusions about specific defense pathways.
Future research should include multi-year, multi-site trials across varying disease pressure conditions, comparison of BmJ efficacy in susceptible versus tolerant cultivars, optimization of application timing and frequency, and economic analysis comparing input cost savings with yield returns to guide grower adoption decisions.