Source: UNIV OF MARYLAND submitted to NRP
ASSESSING EFFECTS OF PREHARVEST ETHYLENE REGULATORS ON PHYSIOLOGICAL DISORDERS, QUALITY, PHENOLIC AND CARBOHYDRATE CONTENTS ON HONEYCRISP APPLES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
ACTIVE
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1030282
Grant No.
2023-68008-39851
Cumulative Award Amt.
$300,000.00
Proposal No.
2022-10033
Multistate No.
(N/A)
Project Start Date
May 1, 2023
Project End Date
Apr 30, 2026
Grant Year
2023
Program Code
[A1701]- Critical Agricultural Research and Extension: CARE
Recipient Organization
UNIV OF MARYLAND
(N/A)
COLLEGE PARK,MD 20742
Performing Department
(N/A)
Non Technical Summary
Incidence of physiological disorders and reduced fruit quality throughout cold storage are major stakeholder-identified factors limiting production and marketability of the profitable apple 'Honeycrisp' in the Mid-Atlantic. To avoid chilling injury, fruits are submitted to a conditioning treatment prior to storage. However, conditioning exacerbates bitter pit expression. Furthermore, growers delay 'Honeycrisp' harvest to meet color requirements, but overripe fruit has an increased risk of developing chilling injury. Hence, resulting in dramatic yield and economic losses. Preharvest ethylene regulators are a promising technology for reducing chilling injury, while eliminating fruit conditioning, and allowing harvesting fruit at optimum maturity. Our goal is to develop and establish a preharvest ethylene regulator treatment for decreasing 'Honeycrisp' disorders, improving phenolic and carbohydrate content, while maintaining quality. Specific objectives are to: 1) determine the effect of preharvest ethylene treatments on reducing physiological disorders and ripening patterns, by conducting a large screening study; 2) evaluate the impact of two most effective treatments on fruit drop, quality, ethylene metabolism, phenolic content and antioxidant activity; 3) assess the impact of the optimum treatment on carbohydrate metabolism; 4) educate stakeholders, through diverse extension venues, on (a) applicability/ effects of the technology, (b) tools for determining optimum harvest, (c) strategies for improving quality and reducing disorders. We anticipate this project will increase apple production efficiency by decreasing losses, improving marketability. It addresses the Critical Agriculture Research and Extension (CARE) program area priority, developing solutions to problems associated with AFRI priorities: (A) Plant health, Production, Plant Products, (C) Food Safety, Nutrition, Health.
Animal Health Component
50%
Research Effort Categories
Basic
50%
Applied
50%
Developmental
0%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
5031110102035%
5031110100035%
5031110104030%
Knowledge Area
503 - Quality Maintenance in Storing and Marketing Food Products;

Subject Of Investigation
1110 - Apple;

Field Of Science
1040 - Molecular biology; 1000 - Biochemistry and biophysics; 1020 - Physiology;
Goals / Objectives
Objective 1: Determine the effect of preharvest ethylene regulator treatments on reducing the incidence of physiological disorders, and fruit ripening patterns in 'Honeycrisp' apples.This first objective will function as a large screening study where we will assess the effect of three preharvest ethylene regulator treatments with different modes of action, and a control, on the incidence of physiological disorders and effects on ripening patterns of 'Honeycrisp' apples. The fruits will be harvested at two different maturity stages and then submitted to long-term storage (3ºC for 24 weeks + 20ºC for 1 week) with or without a conditioning treatment (10ºC for 1 week).Objective 2: Evaluate the effect of selected preharvest ethylene regulator treatments on fruit drop, quality, ethylene metabolism, accumulation of phenolic compounds and antioxidant activity in 'Honeycrisp' apples.Two select optimized treatments from objective 1(one from each maturity stage at harvest), along with a control (in each case), will be evaluated for their impact on preharvest fruit drop, quality, ethylene metabolism, phenolic metabolic-related pathways, and antioxidant activity in 'Honeycrisp' during preharvest, harvest, and cold storage (3ºC for 24 weeks + 20ºC for 1 week).Objective 3: Assess the impact of the selected preharvest ethylene regulator treatment on starch and sugar metabolism in 'Honeycrisp' apples.The most effective treatment selected from Objective 2, along with a control, will be used to assess its impact on starch and sugar metabolism-related pathways, at the gene, enzyme, and metabolites levels at harvest and throughout long-term cold storage (3ºC for 24 weeks + 20ºC for 1 week).Objective 4: Develop educational resources for growers and packers and extension-led outreach efforts to facilitate information dissemination and implementation.Effective extension and outreach efforts will be critical to deliver the knowledge and tools developed from this study to stakeholders that include apple growers, packers, Extension educators and regional specialists. We will demonstrate and train growers on the use of preharvest plant growth regulators and their effects on fruit preharvest through postharvest, on assessments of widely-used fruit harvest indices for apple optimum harvest maturity, as well as on pre- and postharvest management strategies to maintain optimal quality and prevent physiological disorders. Our extension efforts will also be targeted towards "underserved" Latino communities.
Project Methods
Objective 1This first objective will function as a large screening study where we will assess the effect of three preharvest ethylene regulator treatments with different modes of action, and a control, on the incidence of physiological disorders and effects on ripening patterns of 'Honeycrisp' apples. The fruits will be harvested at two different maturity stages and then submitted to long-term storage (3ºC for 24 weeks + 20ºC for 1 week) with or without a conditioning treatment (10ºC for 1 week).Fruits from all treatments will be evaluated at time of spray, at harvest, after conditioning (if applicable), and after 4, 8, 12, 16, 20, 24 weeks of storage at 3ºC followed by shelf-life (7 days at 20ºC).Measurements that we will perform, include: Assessment of fruit ripening patterns, Determination of the incidence of fruit physiological disorders (chilling injury (soft scald and soggy breakdown) and bitter pit)).Objective 2Two select optimized treatments from objective 1(one from each maturity stage at harvest), along with a control (in each case), will be evaluated for their impact on preharvest fruit drop, quality, ethylene metabolism, phenolic metabolic-related pathways, and antioxidant activity in 'Honeycrisp' during preharvest, harvest, and cold storage (3ºC for 24 weeks + 20ºC for 1 week).Measurements that we will perform, include: Preharvest fruit drop, Assessment of fruit ripening patterns, Evaluation of fruit physicochemical properties, Determination of the incidence of fruit physiological disorders, Assessment of fruit ethylene metabolism (gene expression), Evaluation of fruit phenolic metabolism (key phenolic metabolism-related gene expression and metabolite accumulation), and Antioxidant activityObjective 3The most effective treatment selected from Objective 2, along with a control, will be used to assess its impact on starch and sugar metabolism-related pathways, at the gene, enzyme, and metabolites levels at harvest and throughout long-term cold storage (3ºC for 24 weeks + 20ºC for 1 week).Objective 4We will take a four-part approach to transfer information to apple growers, packers, Extension educators and regional specialists and keep them involved in our findings.Field days/ twilight meetings: We will hold annual field days every summer, in partnership with 78Acres, with support from our key personnel and Extension collaborators. The main goals of the field days will be to: 1) provide information on use of plant growth regulators and their impact in fruit maturity and quality, 2) provide training/demonstrations on fruit harvest indices and their interpretation for defining optimum harvest maturity, 3) provide information on the harvest maturity stage of their own fruit in their nearby orchards, 4) increase stakeholders' awareness of the increased preharvest drop and incidence of physiological disorders when harvest is delayed, 5) increase audience knowledge of pre- and postharvest management strategies to maintain fruit quality while minimizing physiological disorders, 6) publicize findings of the proposed research and address questions, and 7) receive feedback and input from participants.Annual meetings and conferences: Results and recommendations will be presented at local and regional meetings. Regionally, results will be presented, in English and Spanish sessions, at the Mid-Atlantic Fruit and Vegetable Convention in Hershey, PA.Extension publications: We will distribute information via newsletters, such as 'Vegetable and Fruit Headline News' (VFHN) from UMD extension (read by ~2,500 stakeholders) and through MSHS. We will also distribute information in Spanish through our newly created (2020) UMD Extension blog in Spanish edited and administered by the PD (Farcuh). Another key extension document corresponds to Fruit Times from Penn State Extension (read by ~ 4,000 stakeholders) and their Facebook page in Spanish.Workshops: We plan to develop a half day workshop for apple growers and packers in the Mid-Atlantic, at the WMREC (Keedysville) in years 2, 3 and beyond the grant funding period. The workshop will focus on 'Pre- and postharvest management practices for decreasing apple physiological disorder incidence while maintaining fruit quality'.

Progress 05/01/24 to 04/30/25

Outputs
Target Audience:The target audiences for this reporting period, includes: • Graduate and undergraduate Students • Grower organizations (Maryland State Horticultural Society, State Hoticultural Association of Pennsylvania) • Apple growers and packers • Extension educators • Applied researchers • Stakeholders • Researchers • Latino communities (Spanish speakers) Changes/Problems:The most critical problem/changes we have is that onApril 23, 2025 I was informed that USDA-NIFA had put "on hold" this award and paused issuance of grant funding. Without funding we cannot move forward with the project as planned. This is very unexpected and we would appreciate guidance on how long will the pause of issuance of grant funding for this award last, for planning purposes. Another important problem is that during the previous reporting period (first year of the project) we reported that we had problems identifying a graduate student that could start working on the project dueto Visa related problems and timings. This has delayed the project 1 year and thuswe are planning on requesting a no-cost extension of the project before the end of the project next year. What opportunities for training and professional development has the project provided?Main opportunities for training include: • Training of graduate students in the field of apple fruit harvest, postharvest biology, and Extension • Training of undergraduate students in the field of apple fruit harvest, postharvest biology, and Extension • Training of stakeholders in the topics of use of optimum management practices related to preharvest plant growth regulators as well as on the development of physiological disorders in apple cultivars, and how important defining optimum apple harvest timings are to avoid quality issues How have the results been disseminated to communities of interest?In addition to all the four-part approach to transfer information to apple growers, packers, Extension educators and regional specialists and keep them involved in our findings (particularly as described for Objective 4) we are also contributing to make this information accessible for underserved communities such as the Latino communities. For this, we have contributed to the first with blog posts linked to the topics of the grant through our Extension Blog in Spanish at the University of Maryland. This blog was developed purely for outreach with the purpose of enhancing public understanding in the field of plant sciences (Link: https://extensionesp.umd.edu/). What do you plan to do during the next reporting period to accomplish the goals?We have several plans for thenext reporting period, that I will list below, but all this plans might not be able to be fulfilled as on April 23, 2025 I was informed that USDA-NIFA had put "on hold" this award and paused issuance of grant funding. As we areuncertain on how long this funding pause will last it is difficult to be able to commit to what wil be achieved during the next reporting period. In the scenario thatthe funding continues to be paused, there are no plans to achieve for the next reporting period as there is no grant money. In the scenario that the pause of funding is removed promptly, the plans for the next reporting period would include: • Workon accomplishing Objective 2: it is expected to complete the first year of evaluation for this objective • Continue working on Objective 4: Develop educational resources for growers and packers and Extension-led outreach efforts to facilitate information dissemination and implementation. In addition to educating growers throughout the venues of field days, conferences/meetings, and extension newsletters, we are also planning to start developing and organizing a half-day workshop with a focus on 'Pre- and postharvest management practices for decreasing apple physiological disorder incidence while maintaining fruit quality'. • Analyzing data and writing up our results for Objective 1 to start putting together a scholarly publication in a peer-reviewed journal. • Training more students (graduate and undergraduates, and maybe a postdoc) • Meet with our Advisory Panel • Start planning for Objective 3 We would appreciate guidance on how long will the pause of issuance of grant funding for this award will last for planning purposes.

Impacts
What was accomplished under these goals? Objective 1: Determine the effect of preharvest ethylene regulator treatments on reducing the incidence of physiologicaldisorders, and fruit ripening patterns in 'Honeycrisp' apples. In this reporting period we were able to complete Objective 1 as we finally were able to have a graduate student working in the project. Weidentified an orchard, applied the treatments and were able to succesfully conduct the measurements. Objective 4: Develop educational resources for growers and packers and Extension-led outreach efforts to facilitateinformation dissemination and implementation.During this reporting period we were invited to participate and deliver talks in multipleregional and local conferences/meetings where we contributed to the fulfillment of this objective by discussing with the attendeesa general overview of our efforts to decrease physiological disorders, besides describing what they are and how can they be reduced. Our PA Extension educator collaborators also helped us distribute this information through local talks at field days thattheydeliveredthroughoutPA. The advisory panel meeting was held during the reporting period where we were able to discuss the plans for the future year and what we had accomplished on the previous one, as well as receivevaluable feedback. Additionally, we also distributed information vianewsletters or Extension publications mainly through 'Vegetable and Fruit Headline News' (VFHN) from UMD.

Publications


    Progress 05/01/23 to 04/30/24

    Outputs
    Target Audience:The target audiences for this reporting period, includes: • Graduate and undergraduate Students • Grower organizations (Maryland State Horticultural Society, State Hoticultural Association of Pennsylvania) • Apple growers and packers • Extension educators • Applied researchers • Stakeholders • Researchers • "Underserved" communities (particularly Latino communities) Changes/Problems:We had problems identifying a graduate student that could start working on the project during this reporting period (due mainly to Visa related problems and timings as well as the fact that I was on maternity leave for the first semester of 2023) which delayed our project. Although we did work with other students that are part of the lab, we still need this coming reporting period to fulfill Objective 1. Thus, we will be requesting a no-cost extension of theproject. We do have a new PhD student identified that will start working for the next reporting period and continuing the work started. What opportunities for training and professional development has the project provided?Main opportunities for training include: • Training of graduatestudents in the field of apple fruit harvest, postharvest biology, and Extension • Training of graduate and undergraduate students in the field of apple fruit harvest, postharvest biology, andExtension • Training of stakeholders in the topics of use of optimum management practices related to preharvest plant growth regulators as well as on the development of physiological disorders in apple cultivars, and how important defining optimum apple harvest timings are to avoid quality issues How have the results been disseminated to communities of interest?In addition to all the four-part approach to transfer information to apple growers, packers, Extension educators and regional specialists and keep them involved in our findings (particularly as described for Objective 4) we are also contributing to make this information accessible for underserved communities such as the Latino communities. For this, we have contributed to the first with blog posts linked to the topics of the grant through our Extension Blog in Spanish at the University of Maryland. This blog was developed purely for outreach with the purpose of enhancing public understanding in the field of plant sciences (Link: https://extensionesp.umd.edu/). For our next reporting period we will also develop a workshop as proposed in the grant. What do you plan to do during the next reporting period to accomplish the goals?During the next reporting period we plan to: • Continue working on accomplishing Objective 1: We have already found a graduate student that will be working on this project and the student is committed to helping us fulfill this objective this coming Fall 2024. • Continue working on Objective 4: Develop educational resources for growers and packers and extension led outreach efforts to facilitate information dissemination and implementation. In addition to educating growers throughout the venues of field days, conferences/meetings, and extension newsletters, we are also planning to start developing and organizing ahalf-day workshop with a focus on 'Pre- and postharvest management practices for decreasing apple physiological disorder incidence while maintaining fruit quality'. • Analyzing data and writing up our results for Objective 1 to start putting together a publicationin a peer-reviewed journal. • Training more students (graduate and undergraduates) • Meet with our Advisory Panel • Start planning for Objective 2

    Impacts
    What was accomplished under these goals? Objective 1: Determine the effect of preharvest ethylene regulator treatments on reducing the incidence of physiological disorders, and fruit ripening patterns in 'Honeycrisp' apples. In this reporting period we started to work on this objective by defining the orchard block we would use and trying out the different treatments. Nevertheless, the objective could not be accomplished due to problems with getting the graduate student onboard timely (I was on maternity leave and the student had issues with the VISA, so we will need to apply for a one year extension for this project). For the next reporting period we are ready to start accomplishing Objective 1 fully. Objective 4: Develop educational resources for growers and packers and extension-led outreach efforts to facilitate information dissemination and implementation.During this reporting period we participated in the Twilight Tour at Western MD Research Station (WMREC)where we shared with the attendees (apple growers) a general overview of our efforts to increase apple fruit quality and how plant growth regulators affect quality andphysiological disorders.We also participated in several regional and local conferences/meetings where we contributed to the fulfillment ofthis objective in English and Spanish (i.e. presented in local Maryland and Pennsylvania grower meetings (English), participated in the Mid-Atlantic Fruit and Vegetable Convention in Hershey, PA delivering 2 presentations (one in English and one in Spanish, touching on the topic of this project). Our PA Extension educator collaborators also helped us distribute this information through local talks they are delivering in PA. The advisory panel meeting was held during the reporting period where we were able to present the detailed project, our plans for the future and get valuable feedback.Additionally, we also distributed information via newsletters or Extension publications mainly through 'Vegetable and Fruit Headline News' (VFHN) from UMD.

    Publications

    • Type: Other Status: Submitted Year Published: 2023 Citation: Plant growth regulators and their effects on fruit quality. Harvest and Farcuh, M. Postharvest Practices for Improving Apple Fruit Marketability: Fruit Quality and Safety Workshop. Western Maryland Research and Education Center, Keedysville, MD, USA, Nov 7, 2023.
    • Type: Other Status: Published Year Published: 2023 Citation: Farcuh, M. Apple fruit physiological disorders and their effects on fruit quality. Harvest and Postharvest Practices for Improving Apple Fruit Marketability: Fruit Quality and Safety Workshop. Western Maryland Research and Education Center, Keedysville, MD, USA, Nov 7, 2023.