Source: COLORADO STATE UNIVERSITY submitted to NRP
MANAGEMENT STRATEGIES TO MAXIMIZE ORCHARD PRODUCTIVITY AND QUALITY POTENTIAL
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
1009721
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Jul 1, 2016
Project End Date
Jun 30, 2021
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
COLORADO STATE UNIVERSITY
(N/A)
FORT COLLINS,CO 80523
Performing Department
Horticulture and Landscape Architecture
Non Technical Summary
Tree fruit such as stone (peach, sweet cherry) and pome fruit (apple and pear) production in the west is threatened by environmental stresses such as diminishing water supplies, spring frosts, low winter temperatures, alkaline soils, soil health and pest problems. The Colorado tree fruit industry is also challenged by un-balanced production and marketing limitations. Well adopted genetic material (rootstocks and cultivars) and optimal cultural management practices are critical to mitigating environmental stresses, such us mid-winder or spring frosts,and improving orchard productivity and tree fruit quality. Additionally, precocity and entrance in fruit production early are important for orchard profitability.In spite of the limited literature available on the role of pre-harvest factors in consumer quality, there is strong evidence that fruit flavor quality, market life and physiological disorders are related to pre-harvest factors. Colorado tree fruit are known for their superior quality associated with the state's unique climatic conditions. However, consistent quality at harvest and proper postharvest handling are necessary to maintain quality and increase consumer acceptance. Judging fruit maturity by shape and color alone results in varying success. Traditional methodology to measurequality of tree fruit isdestructive, time consuming, and require separate measurement protocols for each single quality index, making it hard to adopt them for field measurements.The lack of effective alternatives to control orchard replant disease (RD)in conventional and organic stone fruit production systems, creates an urgent need to find environmentally sound and sustainable solutions to RD management. Herein we propose a research-extension-producer team approach to identify peach RD etiology, evaluate sustainable alternative strategies to manage this disease andimpact farmer decision-making by sharing results through multiple methods.Understanding environmental bases fortree-fruit coldhardiness and damage is of critical importance for resilient Colorado tree-fruit production. This project seek todevelop reliable toolsto determinelethal temperatures of stone fruitfloralbudsunder CO climaticconditions andprovidegrowers accurate dataon currentcultivars cold hardiness tomake informed frost control decisions. In addition,horticulturalpractices andgeneticmaterial (cultivars and rootstocks) will be evaluated to mitigate or avoid cold damage.The general aim of this project is to provide Colorado growers with knowledge and technology to produce more value added fruit with less inputs and consumers fruit of superior quality.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2051119102040%
2041119100030%
5031119100030%
Knowledge Area
204 - Plant Product Quality and Utility (Preharvest); 205 - Plant Management Systems; 503 - Quality Maintenance in Storing and Marketing Food Products;

Subject Of Investigation
1119 - Deciduous tree fruits, general/other;

Field Of Science
1000 - Biochemistry and biophysics; 1020 - Physiology;
Goals / Objectives
General goal: Provide Colorado growers with knowledge and technology to produce more value added fruit with less inputs and consumers fruit of superior quality.Goal 1: Advanced understanding of the fundamental principles affecting tree fruit productivity,harvest and postharvest quality with emphasis on environmental and orchard factors. Development of sustainable orchard and postharvest management strategies that improve the economic and environmental aspects of tree fruit production in Western Colorado.Objective 1.Develop improved orchard management practices towards optimizing productivity, tree precocity, fruit quality and orchard viability both from a biological and economic perspective.Objective 2. Develop and adopt innovative non-destructive maturity/quality indices to accurately estimate tree-fruit quality.Objective 3. Increase understanding of the effect of environmental and pre-harvest factors on fruit harvest and postharvest quality.Objective 4.Developsustainable peach orchard soil microbiome management practices to control replant disease syndromeObjective 5.Mitigatecold damage in Colorado tree-fruitGoal 2: Information needed to improve pre-harvest and soil management practices and harvest/postharvest handling as well ascold hardinesswill be provided to the Colorado tree fruit growers through Extension-organized fruit crop management workshops and field days; through AES and Extension publications; and through a CSU-Pomologywebsite.
Project Methods
Goal 1Objective 1: Develop improved orchard management practices towards optimizing productivity, tree precocity, fruit quality and orchard viability both from a biological and economic perspectiveA field study to compare peach and sweet cherry training/canopy management systems, different rootstocks, and tree densities will be established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. These two experimental plots will be used as showcase sites for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices (summer pruning, fertigation, foliar nutrition etc.). Data collected will include date of bloom, date of ripening, tree-growth, fruit yield, and fruit quality. Objective 2: Develop and adopt innovative non-destructive maturity/quality indices to accurately estimate tree-fruit quality A laboratory study will provide the data needed to create new quality models for two different hand-held non-destructive sensors. One uses short-wave near infrared spectrometry and the other Vis/NIR spectroscopy to estimate tree fruit quality through different developmental stages, at commercial harvest, and during postharvest storage. This analysis will be performed on peach, apple and sweet cherry.Fruit selected across a range of maturity and size will be scanned using the different non-destructive sensors at room temperature (20oC). Subsequently, the same fruit regions scanned with the sensors will be destructively measured for dry matter (DM), soluble solids concentration (SSC), titratable acidity, (TA), firmness and flesh color. The resulting regression data will be analyzed for linearity, root mean square error, and leave-one-out cross validation error to determine the applicability and accuracy of the created model. A second population of fruit will be measured immediately after harvest and during postharvest storage with the non-destructive sensors, and the data will be used to independently validate the models.Objective 3: Increase understanding of the effect of environmental and pre-harvest factors on fruit harvest and postharvest qualityData will be taken in different experimental plots at Colorado State University's WCRC-OM experimental orchard with different cultivars and rootstocks as well as with different training systems and cultural and canopy management strategies. Fruit from different experiments will be assessed for quality and storage potential with destructive and non-destructive methods to investigate the role of environmental and pre-harvest factors on fruit harvest quality and postharvest storage potential.Objective 4:Developsustainable peach orchard soil microbiome management practices to control replant disease syndromeApplication of high-thoughtput molecular techniques will enable identification of the beneficialmicrobial components that mitigate peach replant disease (RD)symptoms to be used in commercial orchard systems. Replant disease-tolerant peach rootstocks will be evaluated in greenhouse, agricultural experimental stations and on-farm trials in organic and conventional commercial orchards. Throught this bottom-up research and extension/outreach approach we will generate solid information on RD etiology and sustainable management strategies for conventional and organic peach production systems to improve soil health,increase orchard productivity and longevity and grower profitability.Objective 5:Mitigatecold damage in Colorado tree-fruitSpecially constructed equipment that utilizes thermoelectric modules (TEM) and a Tenney Jr programmable freezer (-80 to +200 °C) will be used for differential thermal analysis (DTA) to estimate cold hardiness of peach floral buds coming from trees of different cultivars,distinct canopy architectures, rootstocks and cultural management treatments. Data collected under this objective will be reported to local Colorado growers freequently throughthe CSU Pomology webpage and appropriate email frost alerts will be send to Fruit Facts registered growerswhen necessary.Goal 2Information needed to improve pre-harvest and soil management practices and harvest/postharvest handling as well ascold hardinesswill be provided to the Colorado tree fruit growers through Extension-organized fruit crop management workshops and field days; through AES and Extension publications; and through a CSU-Pomologywebsite.

Progress 07/01/16 to 06/30/21

Outputs
Target Audience:Scientific community, tree fruit growers, extension personnel and CSU students. Changes/Problems:An early Fall frost in 2020 (October 25-27, 2020), followed by a late Spring frost in 2021, severely damaged both thereproductive and vegetative tissue across all trees mostly in cherry trees and for the rest of the dormant and spring seasonwe have been using this trials to understand tree damage and responses for grower information. A new pruning strategy wasemployed to re-start/re-invigorate the trees and manage damaged fruiting wood was applied in the cherry trial in spring 2021.By heading back all of the trees (regardless of training system x rootstock treatment) to approximately 1 - 1.5 m aboveground. Training systems were then re-trained throughout the 2021 growing season. Pruning response data to the wholetree renewal strategy are being currently collected. What opportunities for training and professional development has the project provided?Research associates located in the WCRC-OM are now trained in the use of new technologies to estimate fruit quality as well as on new pruning/training techniques. Several tours of diverse groups of people (CSU undergraduate students, commercial growers, backyard gardeners, CSUhorticultural extension agents) have been visited the peach and cherrytrials at WCRC-OM and had an opportunity tounderstand the importance of training system selection for tree precocity and productivity in western Colorado conditions.Based on the results of this project new trials are being planted to transform peach cropping systems for the future. Additionally, during the growing season of 2016, 2017 and2018, 202new and accurate internal quality [measured as dry matter (DM) and soluble solids concentration (SSC)], and maturity [chlorophyllcontent (IAD)] models using a hand-held non-destructive sensor (Felix F-750) that uses near infraredspectrometry. These models were utilized to study the effect of the different rootstocks, of different canopy managementstrategies (pruning styles and training systems),on fruit quality both in WCRC-OM and in differentcommercial growers blocks. How have the results been disseminated to communities of interest?An update on the CSU Pomology program was given at the 2020 and 2022 Western Colorado Horticultural Society's annual meetingin Grand Junction, CO with over 5 talks from members of the CSU Pomology Group (the 2021 meeting was canceled and we provided a webinar). A CSU Pomology website was developed were all reports, presentations and updates are postedand shared with stakeholders through email updates. One of the most important services to our stakeholders is the peachfloral bud weekly cold hardiness updates that are being posted to our CSU Pomology website and communicated withstakeholders through the Fruit Facts emailing list. Last dormant (2019/20) season 21 updates were posted: Sterle DG, Minas IS (2020). Cold hardiness assessment of peach flower buds using differential thermal analysis (DTA) inwestern Colorado (dormant season 2019-20). CSU Pomology web page, 21 updates. https://minas.agsci.colostate.edu/wpcontent/uploads/sites/60/2020/02/Peach-floral-bud-cold-hardiness-update-21-2_14_20.pdf During the previousdormant season (2020-21)20updates were posted. Sterle DG, Minas IS (2021). Cold hardiness assessment of peach flower buds using differential thermal analysis (DTA) inwestern Colorado (dormant season 2020-21). CSU Pomology web page, 20updates. https://minas.agsci.colostate.edu/wpcontent/uploads/sites/60/2021/02/Peach-floral-bud-cold-hardiness-update-20-01_26_21.pdf A beginner growers' workshop on principles in fruit production was organized in January 2020 (30 attendees) and informedand trained tree fruit growers with the most research findings of this project. A Webinar on CSU Pomology Research Program at Western Colorado Research Center at Orchard Mesa (WCRC-OM) updates and Tree Fruit Pruning and Training after the October 2020 cold damage was organizedin February 2021 under the frame of Western Colorado Horticultural Society (WCHS) with 65 attendees. A 'Pruning & Training:Peaches & Cherries following freeze damage' workshopwas organized in January 2021(45attendees) and informedand trained tree fruit growers with the most research findings of this project. Invited talks: Minas IS, Revealing the True Impact of Orchard and Preharvest Factors on Peach Fruit Quality Development and Postharvest Performance. ASHS Webinar, January 2021. Minas IS, Revealing the True Impact of Preharvest Factors on Peach Fruit Quality Development & Metabolism. Keynote speaker at ISHS Peach Webinar in the frame of 2022 International Peach Conference, June 2021. Minas IS, Unraveling the true impact of orchard factors on peach fruit quality development using accurate & rapid non-destructive sensors. Invited Talk at Planned Oral Session at Annual ASHS Conference, Denver, CO, August 2021. Minas IS, Orchard & Environmental Factors Affecting Peach Productivity & Harvest Quality, Great Lakes EXPO, Grand Rapids, MI, December 2021. Media appearances: https://www.denverpost.com/2021/04/20/colorado-palisade-peaches-orchards-freeze-snow/#comments-anchor https://coloradosun.com/2021/04/22/colorado-peach-forecast-ela-family-farms/ What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Goal 1 Objective 1 Peach training systems trial A field study to compare peach training/canopy management systems, different rootstocks, and tree densities hasbeen established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Red Haven treesgrafted on St. Julien rootstock and O'Henry trees grafted on Krymsk 86 were planted in different distances among them in therows in May 3, 2016. These trees were trained in Open Vase, Hex V, Quad V, Tall Spindle Axe (TSA), KAC-V and Bi- Axe.This experimental plot is used as showcase site for workshops and field days as well as for research. In addition to the mainobjective of this study several other research experiments will be conducted to include different cultural practices. In 2019 atthe 4th leaf of the trial we harvested the first crop. With TSA being the most precocious. In 2020, a spring frost in April 14thkilled 99% of peach floral buds and for the rest of the season we managed the trees and tree survival and growth datawere collected. In October 25-27, 2020 an early freeze caused damage in trees and for the rest of the dormant season wehave been using this trial to understand tree damage and responses for grower information. A new pruning strategyto managedamaged fruiting wood will be applied in this trial as we move towards to the sixth leaf and a good crop year is expected. Details on the trial results presented innumerous invited talks and grower education activitiesand summarized in Anthony and Minas(2021) paper. Sweet cherry training systems trial A field study to compare sweet cherry training/canopy management systems, different rootstocks, and tree densities hasbeen established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Bing cherry treesgrafted on Krymsk 6 and Gisela 6 and Skeena cherry trees grafted on Krymsk 6 and Gisela 6 were planted in differentdistances among them in the rows in May 4, 2016. These trees were trained in Upright Fruiting Offshoots (UFO), Superslender axes (SSA), Bi-Axe, Tall Spindle Axe (TSA) and Kym Green Bush (KGB). This experimental plot is being usedas showcase site for workshops and field days as well as for research. In addition to the main objective of this studyseveral other research experiments will be conducted to include different cultural practices. In the fifth leaf (2020) we did notharvest any fruit as a result of the April 14 frost (as mentioned above). In October 25-27 cherries were active and green andthey were severely damaged from the freeze. No crop was harvested in2021 but the block was used for tree recovery afterfreeze damage trials. Tree survival and growth werecollected. Peach varieties trial A field study to evaluate different peach cultivars in western Colorado conditions was established in May 3 and 5, 2016at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Glohaven/Lovell,Glowingstar/Lovell, Blushingstar/Lovell, Starfire/Lovell, Newhaven/Lovell Flamin Fury PF 19-007/Lovell, Flamin Fury PF23/Lovell, Flamin Fury PF 24 Cold Hardy/Lovell, Red Haven/Lovell, August Lady/Hansen 536, Ryan Sun/Hansen 536 RedHaven/St. Julien and O'Henry/Krymsk 86 trees were planted in a completely randomized block design of 8 replicates. Thisexperimental plot is used as showcase site for workshops and field days as well as for research. Data collected in thissixth leaf season (2021) include tree growth, survival and cold hardiness using differential thermal analysis (DTA) as wellcultivar performance to the various freeze events and these particular findings are very important for the industry. Objective 2 Fruit internal quality prediction models have been successfully developed for 'Sierra Rich' and 'Cresthaven' peachcultivars that can accurately estimate internal fruit quality [dry matter content (DMC) and soluble solids concentration (SSC)],and maturity [chlorophyll content (IAD)] through a hand-held non-destructive sensor (Felix F-750) that uses short-wavenear infrared spectroscopy (NIRS). An article describing our novel NIRS calibration protocol was published in Food Chemistryand a provisional patent for a concept devise that can assess fruit maturity and internal quality was submitted in 2020.Three more papers on this field are underway. Developed non-destructive models are used to further study the effect of fruitposition in the canopy on fruit quality in collaboration with local commercial peach growers. In addition, these models wereused to estimate internal quality on different peach cultivars to validate model capacity and extend the range of applicability ofthe developed technology. These models are utilized to study in more detail the effect of crop load, rootstock, canopymanagement strategy (pruning styles and training systems), and light environment on fruit quality both in WCRC-OM and indifferent commercial growers' blocksduring the growing season of 2019. The field work was not performed in 2020 due to thelack of crop. The work on this objective continuedin the2021 season with custom models developed for maturity and quality predictions with a single scan across 13 cultivars (see above details on the peach cultivar trial). Objective 3 Effect of crop load on peach and apple fruit quality, tree physiology and dormant bud cold hardiness During the growing season of 2016 different crop load levels were achieved in 'Sierra Rich' and 'Cresthaven' peachesand 'Gala' apples by applying different thinning patterns (unthinned trees, heavy, commercial, and light crop load). Fruitgrowth, maturity and quality were monitored during the growing season with NIR and Vis/NIR non-destructive sensors with themodels mentioned above. Fruit from different crop loads were assessed for internal and external quality and storage potentialwith destructive and non-destructive methods to investigate the effect of crop load on fruit harvest quality and postharveststorage potential. Results, showed that crop load reduced fruit quality and delayed fruit ripening in both apples and peaches.Comprehensive metabolomic studies on peach samples in collaboration with Prenni Lab showed that early metabolic primingunder differing carbon sufficiency (crop load) conditions influences peach fruit quality development. These results werepublished in Plant Physiology and Biochemistry and Environmental and Experimental Botany. Data on 15 peach cultivars during dormant bud acclimation and mid-wintercold hardiness are being collected during for the last dormant five seasons and a prediction model based on weatherparameters has been developed and submitted to Environmental and Experimental Botany. In addition, these data areregularly communicated with our industry via our CSU Pomology website. Data will be collected over the next dormant seasonwith Differential Thermal Analysis (DTA). Effect of rootstocks on peach fruit internal quality During the growing season of 2016, 2017, 2018 and 2019 'Red Haven' fruit coming from the 2009 Peach Rootstock Trialwere utilized to create new internal quality (measured as DMC, SSC), and maturity [chlorophyll content (IAD)] models using ahandheld non-destructive sensor (Felix F-750) that uses short-wave near infrared spectrometry. These models wereutilized to study the effect of the different rootstocks on fruit internal quality. Collectively, following this 3-season field study ithas been demonstrated that tree vigor interferes with fruit internal quality. The more vigorous rootstocks reduced fruit DMCover the dwarfing rootstocks that produced fruit of superior internal qualities. In 2020, we established a comprehensivemetabolomic analysis in collaboration with Prenni Lab to further characterize the impact of rootstock and tree vigor on fruitquality development. Goal 2 See section 'How have the results been disseminated to communities of interest?'

Publications

  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Tanner JD, Chen KY, Bonnart R, Minas IS, Volk GM, 2021. Considerations for large-scale implementation of dormant budwood cryopreservation. Plant Cell, Tissue and Organ Culture (PCTOC), 144, 35-48.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Minas IS*, Blanco-Cipollone F, Sterle D, 2021. Non-destructive assessment of the effect of crop load and canopy position on peach fruit internal quality and harvest maturity using visible and near infrared spectroscopy. Food Chemistry Food Chemistry 335, 127626.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Tanner JD, Chen KY, Jenderek MM, Wallner SJ, Minas IS*, 2021. Determining the effect of pretreatments on freeze resistance and survival of cryopreserved temperate fruit tree dormant buds. Cryobiology 101, 87-94. doi: 10.1016/j.cryobiol.2021.05.003
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Anthony BM, Minas IS*, 2021. Optimizing Peach Tree Canopy Architecture for Efficient Light Use, Increased Productivity and Improved Fruit Quality. Agronomy 11 (10), 1961.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Anthony BM, Chaparro JM, Sterle DG, Prenni JE, Minas IS*, 2021. Metabolic signatures of the true physiological impact of canopy light environment on peach fruit quality. Environmental and Experimental Botany 191, 104630.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Minas IS, Revealing the True Impact of Orchard and Preharvest Factors on Peach Fruit Quality Development and Postharvest Performance. ASHS Webinar, January 2021.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Minas IS, Revealing the True Impact of Preharvest Factors on Peach Fruit Quality Development & Metabolism. Keynote speaker at ISHS Peach Webinar in the frame of 2022 International Peach Conference, June 2021.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Minas IS, Unraveling the true impact of orchard factors on peach fruit quality development using accurate & rapid non-destructive sensors. Invited Talk at Planned Oral Session at Annual ASHS Conference, Denver, CO, August 2021.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Minas IS, Orchard & Environmental Factors Affecting Peach Productivity & Harvest Quality, Great Lakes EXPO, Grand Rapids, MI, December 2021.
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Anthony B, Sterle D, Chaparro J, Prenni J, Minas IS. Comprehensive physiological and metabolomic analysis to identify metabolic signatures of the impact of canopy position on peach fruit quality. Oral Presentation at ISHS XII International Symposium on Integrating Canopy, Rootstock & Environmental Physiology in Orchard Systems, Wenatchee, WA, July 2021.
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Sterle D, Minas IS. Peach floral bud cold hardiness characterization of multiple genotypes using differential thermal analysis. Oral Presentation at ISHS XII International Symposium on Integrating Canopy, Rootstock & Environmental Physiology in Orchard Systems, Wenatchee, WA, July 2021.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Minas IS, Sterle D, Heuberger A, Prenni J. Dissecting peach cold hardiness eco-physiology and metabolism. Oral Presentation at ISHS XII International Symposium on Integrating Canopy, Rootstock & Environmental Physiology in Orchard Systems, Wenatchee, WA, July 2021.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Anthony BM, Chaparro JM, Prenni JE, Minas IS. Variable carbon supply conditions promote early metabolic priming responses related to peach fruit quality development. Oral Presentation at Annual ASHS Conference, Denver, CO, August 2021.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Pieper J, Anthony B, Chaparro J, Sterle D, Prenni J, Minas IS. Rootstock vigor and fruit position in the canopy influence peach internal quality. Oral Presentation at Annual ASHS Conference, Denver, CO, August 2021.


Progress 10/01/19 to 09/30/20

Outputs
Target Audience:Scientific community, tree fruit growers, extension personnel and CSU students. Changes/Problems:Aspring frost on April 14, 2020killed 99% of peach floral buds.For the rest of the season, we managed the treesand tree survival and growth data werecollected. In October 25-27, 2020 an early freeze caused damage in peach trees and mostly in cherry trees.For the rest ofthe dormant season, we have been using this trial to understand tree damage and responses for grower information. A new pruning strategy to manage damaged fruiting wood will be applied in thesetrials as we move towards the spring. In addition, on the cherry trial extensive tree recovery pruning treatments will be applied. What opportunities for training and professional development has the project provided?Research associates located in the WCRC-OM are now trained in the use of new technologies to estimate fruit quality as wellas on new pruning/training techniques. How have the results been disseminated to communities of interest?An update on the CSU Pomology program was given at the 2020Western Colorado Horticultural Society's annual meeting inGrand Junction, CO. A CSU Pomology website was developed were all reports, presentations and updates are posted andshared with stakeholders through email updates. One of the most important services to our stakeholders is thepeach floralbud weekly cold hardiness updates that are being posted to our CSU Pomology website and communicated with stakeholdersthrough the Fruit Facts emailing list. Last dormant (2019/20) season 21updates were posted. Sterle DG,Minas IS(2020). Cold hardiness assessment of peach flower buds using differential thermal analysis (DTA) in western Colorado (dormant season 2019-20).CSU Pomology web page, 21 updates.https://minas.agsci.colostate.edu/wp-content/uploads/sites/60/2020/02/Peach-floral-bud-cold-hardiness-update-21-2_14_20.pdf During the current dormantseason 21updates have been posted so far. Sterle DG,Minas IS(2021). Cold hardiness assessment of peach flower buds using differential thermal analysis (DTA) in western Colorado (dormant season 2020-21).CSU Pomology web page, 20 updates.https://minas.agsci.colostate.edu/wp-content/uploads/sites/60/2021/02/Peach-floral-bud-cold-hardiness-update-20-01_26_21.pdf A beginner growers'workshop on principles in fruit productionwas organized in January 2020 (30 attendees),andinformed andtrained tree fruit growers with the most research findings of this project. What do you plan to do during the next reporting period to accomplish the goals?Quality prediction models created using a NIR non-destructive sensor are going to be utilized over the next growing season(2021) to provide a deeper understanding of the effect of cultivar, tree canopy architecture, and light environment on peachfruit quality. Additionally, the same sensor will be utilized to study the effect of different pruning stylesand fruitposition in the canopy on peach fruit quality. Data on 'Suncrest', 'Sierra Rich', 'Cresthaven' and 'Red Haven' and eleven more cultivars duringpeach dormantbud acclimation, mid- winter, and bud break cold hardiness are being collected during the dormant season of 2020/21withDifferential Thermal Analysis (DTA) and weekly updates on cold hardiness status of those cultivars are going to be posted inCSU Pomology web site. Data on tree growth, health, yield will be collected.

Impacts
What was accomplished under these goals? Goal 1 Objective 1 Peach training systems trial A field study to compare peach training/canopy management systems, different rootstocks, and tree densities has beenestablished at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Red Haven trees graftedon St. Julien rootstock and O'Henry trees grafted on Krymsk 86 were planted in different distances among them in the rows inMay 3, 2016. These trees were trained in Open Vase, Hex V, Quad V, Tall Spindle Axe (TSA), KAC-V and Bi- Axe. This experimental plot is used asshowcase site for workshops and field days as well as for research. In addition tothe main objective of this study several other research experiments will be conducted to includedifferent cultural practices. In 2019 at the 4th leaf of the trialwe harvested the first crop, with TSA being the most precocious. In 2020 a spring frost in April 14th killed 99% of peach floral buds and for the rest of the season we managed the treesand tree survival and growth data werecollected. In October 25-27, 2020 an early freeze caused damage in trees and for the rest ofthe dormant season we have been using this trial to understand tree damage and responses for grower information. A new pruning strategy to manage damaged fruiting wood will be applied in this trial as we move towards to the sixth leaf and a good crop year is expected. Sweet cherry training systems trial A field study to compare sweet cherry training/canopy management systems, different rootstocks, and tree densities has beenestablished at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Bing cherry trees graftedon Krymsk 6 and Gisela 6 and Skeena cherry trees grafted on Krymsk 6 and Gisela 6 were planted in different distancesamong them in the rows in May 4, 2016. These trees were trained in Upright Fruiting Offshoots (UFO), Super slender axes(SSA), Bi-Axe, Tall Spindle Axe (TSA) and Kym Green Bush (KGB). This experimental plot isbeing used asshowcase site for workshops and field days as well as for research. In addition to the main objective of this study, severalother research experiments will be conducted to include different cultural practices. In the fifth leaf (2020) we did not harvest any fruit as a result of the April 14 frost (as mentioned above). In October 25-27 cherries were active and green and they were severely damaged from the freeze. No crop is expected for 2021 but we will used the block for tree recovery after freeze damage trials. Treesurvival and growth data will becollected. Peach varieties trial A field study to evaluate different peach cultivars in western Colorado conditions was established in May 3 and 5, 2016 atColorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Glohaven/Lovell, Glowingstar/Lovell,Blushingstar/Lovell, Starfire/Lovell, Newhaven/Lovell Flamin Fury PF 19-007/Lovell, Flamin Fury PF 23/Lovell, Flamin Fury PF24 Cold Hardy/Lovell, Red Haven/Lovell, August Lady/Hansen 536, Ryan Sun/Hansen 536 Red Haven/St. Julien andO'Henry/Krymsk 86 trees were planted in a completelyrandomized block design of 8 replicates. This experimental plot is used as showcase site for workshops and field days as well as for research. Data collected in this fifthleaf season (2020)include tree growth, survival and cold hardiness using differential thermal analysis (DTA) as well cultivar performance to the various freeze events and these particular findings will be very important for the industry. Objective 2 Fruit internal quality prediction models have been successfully developed for 'Sierra Rich' and 'Cresthaven' peach cultivarsthat can accurately estimate internal fruit quality [dry matter content (DMC) and soluble solids concentration (SSC)], andmaturity [chlorophyll content (IAD)] through a hand-held non-destructive sensor (Felix F-750) that uses short-wave nearinfrared spectroscopy (NIRS). An article describing our novel NIRS calibration protocol was published in Food Chemistry and a provisional patent for a concept devise that can assess fruit maturity and internal quality was submitted in 2020. Threemore papers on this field are underway. Developed non-destructive models are used to further study the effect of fruit position in the canopyon fruit quality in collaboration with local commercial peach growers. In addition, these models were used to estimate internalquality on different peach cultivars to validate model capacity and extend the range of applicability of the developedtechnology. These models are utilized to study in more detail the effect of crop load, rootstock, canopy management strategy(pruning styles and training systems), and light environment on fruit quality both in WCRC-OM and in different commercial growers'blocks during the growing season of 2019. The field work was not performed in 2020 due to the lack of crop. The work on this objective will continue the coming 2021 season. Objective 3 Effect of crop load on peach and apple fruit quality, tree physiology and dormant bud cold hardiness During the growing season of 2016 different crop load levels were achieved in 'Sierra Rich' and 'Cresthaven' peaches and'Gala' apples by applying different thinning patterns (unthinned trees, heavy, commercial, and light crop load). Fruit growth,maturity and quality were monitored during the growing season with NIR and Vis/NIR non-destructive sensors with the modelsmentioned above. Fruit from different crop loads were assessed for internal and external quality and storage potential withdestructive and non-destructive methods to investigate the effect of crop load on fruit harvest quality and postharvest storagepotential. Results showed that crop load reduced fruit quality and delayed fruit ripening in both apples and peaches. Comprehensive metabolomic studiesonpeach samples in collaboration with Prenni Labshowed that early metabolic priming under differing carbon sufficiency (crop load) conditions influences peach fruit quality development. These results were published inPlant Physiology and Biochemistry.Data on 15 peach cultivars duringdormant bud acclimation and mid-winter cold hardiness are being collected during for the last dormant five seasons and a prediction model based on weather parameters has been developed and submitted to Environmental and Experimental Botany. In addition, these data are regularly communicated with our industry via our CSU Pomology website. Datawill be collected over the next dormant season with Differential Thermal Analysis (DTA). Effect of rootstocks on peach fruit internal quality During the growing season of 2016, 2017, 2018 and 2019 'Red Haven' fruit coming from the 2009 Peach Rootstock Trial wereutilized to create new internal quality (measured as DMC, SSC), and maturity [chlorophyll content (IAD)] models using a handheldnon-destructive sensor (Felix F-750) that uses short-wave near infrared spectrometry. These models were utilizedtostudy the effect of the different rootstocks on fruit internal quality. Collectively, following this 3-season field study it has beendemonstrated that tree vigor interferes with fruit internal quality. The more vigorous rootstocks reduced fruit DMC over thedwarfing rootstocks that produced fruit of superior internal qualities. In 2020 we established a comprehensive metabolomic analysis in collaboration with Prenni Lab to further characterize the impact of rootstock and tree vigor on fruit quality development. Goal 2 See section 'How have the results been disseminated to communities of interest?'

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: MINAS IS, STERLE D. Differential thermal analysis sheds light on the effect of environment and cultivar in peach floral bud cold hardiness. Acta Horticulturae 2020, 1281, 385-392.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: MINAS IS, BLANCO-CIPOLLONE F, STERLE D. Near infrared spectroscopy can non-destructively assess the effect of canopy position and crop load on peach fruit maturity and quality. Acta Horticulturae 2020, 1281, 407-412.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: MINAS IS, BLANCO-CIPOLLONE F, STERLE D. Non-destructive assessment of the effect of crop load and canopy position on peach fruit internal quality and harvest maturity using visible and near infrared spectroscopy. Food Chemistry Food Chemistry 2021, 335, 127626.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: ANTHONY B, CHAPARRO J, STERLE D, PRENNI J, MINAS IS. Early metabolic priming under differing carbon sufficiency conditions influences peach fruit quality development. Plant Physiology and Biochemistry 2020, 157, 416-431
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: MINAS IS. The impact of the environment & genotype on peach cold hardiness & damage, Invited Talk to Mid-Atlantic Fruit & Vegetable Convention, Jan 2020, Hershey, PA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: MINAS IS. Pre- & postharvest factors affecting peach fruit quality, Invited Talk to Mid-Atlantic Fruit & Vegetable Convention, Jan 2020, Hershey, PA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: MINAS IS. The peach industry in USA: challenges & opportunities for CO peaches, Invited talk to Western Colorado Horticultural Society Annual Conference, Jan 2020, Grand Junction, CO.


Progress 10/01/18 to 09/30/19

Outputs
Target Audience: Scientific community, tree fruit growers, extension personnel and CSU students. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Research associates located in the WCRC-OM are now trained in the use of new technologies to estimate fruit quality as well as on new pruning/training techniques. How have the results been disseminated to communities of interest? An update on the CSU Pomology program was given at the 2019Western Colorado Horticultural Society's annual meeting in Grand Junction, CO. A CSU Pomology website was developed were all reports, presentations and updates are posted and shared with stakeholders through email updates. One of the most important services to our stakeholders is the peach floral bud weekly cold hardiness updates that are being posted to our CSU Pomology website and communicated with stakeholders through the Fruit Facts emailing list. Last dormant (2018/19) season 24 updates were posted. During the current dormant season 16updates have been posted so far. A pruning and training workshop was organized inJanuary 2019 to inform and train tree fruit growers with the most research findings of this project. What do you plan to do during the next reporting period to accomplish the goals? Quality prediction models created using a NIR non-destructive sensor are going to be utilized over the next growing season (2020), to provide a deeper understanding of the effect of cultivar, tree height, nutrition management and crop load on peach fruit quality. Additionally, the same sensor will be utilized to study the effect of different pruning styles, of shoot size and fruit position in the canopy on peach fruit quality. Data on 'Suncrest', 'Sierra Rich', 'Cresthaven' and 'Red Haven' peach dormant bud acclimation, mid- winter, and bud break cold hardiness are being collected during the dormant season of 2019/20with Differential Thermal Analysis (DTA) and weekly updates on cold hardiness status of those cultivars are going to be posted in CSU Pomology web site. Data on tree growth, health, yield will be collected as in 2019.

Impacts
What was accomplished under these goals? Goal 1 Objective 1 Peach training systems trial A field study to compare peach training/canopy management systems, different rootstocks, and tree densities has been established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Red Haven trees grafted on St. Julien rootstock and O'Henry trees grafted on Krymsk 86 were planted in different distances among them in the rows in May 3, 2016. These trees were trained in Open Vase, Hex V, Quad V, Tall Spindle Axe (TSA), KAC-V and Bi- Axe in spring 2019. This experimental plot will be used as showcase site for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices. For this forth leaf season (2019) trees were trained at final scaffold shapes and tree survival and growth data were collectedas well as and the first fruit were harvested. Sweet cherry training systems trial A field study to compare sweet cherry training/canopy management systems, different rootstocks, and tree densities has been established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Bing cherry trees grafted on Krymsk 6 and Gisela 6 and Skeena cherry trees grafted on Krymsk 6 and Gisela 6 were planted in different distances among them in the rows in May 4, 2016. These trees were trained in Upright Fruiting Offshoots (UFO), Super slender axes (SSA), Bi-Axe, Tall Spindle Axe (TSA) and Kym Green Bush (KGB) in spring 2019. This experimental plot will be used as showcase site for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices. For this forthleaf season (2019) trees were trained at final architectures and tree survival and growth data collected were collected. Peach varieties trial A field study to evaluate different peach cultivars in western Colorado conditions was established in May 3 and 5, 2016 at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Glohaven/Lovell, Glowingstar/Lovell, Blushingstar/Lovell, Starfire/Lovell, Newhaven/Lovell Flamin Fury PF 19-007/Lovell, Flamin Fury PF 23/Lovell, Flamin Fury PF 24 Cold Hardy/Lovell, Red Haven/Lovell, August Lady/Hansen 536, Ryan Sun/Hansen 536 Red Haven/St. Julien and O'Henry/Krymsk 86 trees were planted in a completely randomized block design of 8 replicates. This experimental plot will be used as showcase site for workshops and field days as well as for research. Data collected in this forthleaf season (2019) include tree growth, survival and cold hardiness using differential thermal analysis (DTA). Objective 2 Fruit internal quality prediction models have been successfully developed for 'Sierra Rich' and 'Cresthaven' peach cultivars that can accurately estimate internal fruit quality [dry matter content (DMC) and soluble solids concentration (SSC)], and maturity [chlorophyll content (IAD)] through a hand-held non-destructive sensor (Felix F-750) that uses short-wave near infraredspectroscopy (NIRS). An article describing our novel NIRS calibration protocol was submitted in Food Chemistry and two more are underway.Developed non-destructive models were used to further study the effect of fruit position in the canopy on fruit quality in collaboration with local commercial peach growers. In addition, these models were used to estimate internal quality on different peach cultivars to validate model capacity and extend the range of applicability of the developed technology. These models are utilized to study in more detail the effect of crop load, rootstock, canopy management strategy (pruning styles and training systems), and soil profile on fruit quality both in WCRC-OM and in different commercial growers' blocks during the growing season of 2019. Objective 3 Effect of crop load on peach and apple fruit quality, tree physiology and dormant bud cold hardiness During the growing season of 2016 different crop load levels were achieved in 'Sierra Rich' and 'Cresthaven' peaches and 'Gala' apples by applying different thinning patterns (unthinned trees, heavy, commercial, and light crop load). Fruit growth, maturity and quality were monitored during the growing season with NIR and Vis/NIR non-destructive sensors with the models mentioned above. Fruit from different crop loads were assessed for internal and external quality and storage potential with destructive and non-destructive methods to investigate the effect of crop load on fruit harvest quality and postharvest storage potential. Results showed that crop load reduced fruit quality and delayed fruit ripening in both apples and peaches. Postharvest performance of peaches and apples studied over the fall/winter season of 2016/17. Data on 'Sierra Rich' and 'Cresthaven' peach dormant bud acclimation and mid-winter cold hardiness are being collected during the dormant season of 2016/17 and will be collected over the next dormant season with Differential Thermal Analysis (DTA). Effect of rootstocks on peach fruit internal quality During the growing season of 2016, 2017 and 2019 'Red Haven' fruit coming from the 2009 Peach Rootstock Trial were utilized to create new internal quality (measured as DMC, SSC), and maturity [chlorophyll content (IAD)] models using a hand- held non-destructive sensor (Felix F-750) that uses short-wave near infrared spectrometry. These models were utilized tostudy the effect of the different rootstocks on fruit internal quality. Collectively, following this 3-season field study it has been demonstrated that tree vigor interferes with fruit internal quality. The more vigorous rootstocks reduced fruit DMC over the dwarfing rootstocks that produced fruit of superior internal qualities. Goal 2 See section 'How have the results been disseminated to communities of interest?'

Publications

  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Li K, DiLegge M, Minas IS, Hamm A, Manter D, Vivanco J. Soil sterilization leads to re-colonization of a healthier rhizosphere microbiome. Rhizosphere 2019, 12, 100176.
  • Type: Journal Articles Status: Submitted Year Published: 2019 Citation: Minas IS, Tanou G, Scossa F, Belghazi M, Krokida A, Boghi C, Trainoti L, Fernie A, Papadopoulou KK, Molassiotis A. Exploring priming responses involved in peach fruit quality development as affected by the growing altitude. Submitted in Plant Cell and Environment 2019.
  • Type: Journal Articles Status: Submitted Year Published: 2019 Citation: Minas IS, Blanco-Cipollone F, Sterle D. Non-destructive assessment of the effect of crop load and canopy position on peach fruit internal quality and harvest maturity using visible and near infrared spectroscopy. Submitted in Food Science 2019.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Minas IS. Environmental bases for cold hardiness and damage in peach, Invited talk at 2019 Indiana Horticultural Congress, Indianapolis, IN, February 12-14, 2019.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Minas IS. Pre- and postharvest factors affecting peach fruit quality, Invited talk at 2019 Indiana Horticultural Congress, Indianapolis, IN, February 12-14, 2019.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Minas IS. The peach industry in USA: challenges & opportunities, Keynote talk at International Peach Congress, Freskon 2019, Thessaloniki, Greece, April 11-12, 2019.


Progress 10/01/17 to 09/30/18

Outputs
Target Audience: Scientific community,tree fruit growers, extension personnel and CSU students. Changes/Problems:Cytospora cankers that developedin the new peach plantingsare going to be managed withsurgery cuts and chemical treatmentsto provide practical information/solution to tree fruit growers. What opportunities for training and professional development has the project provided?Research associates located in the WCRC-OM are now trained in the use of new technologies to estimate fruit quality as well as on new pruning/training techniques. How have the results been disseminated to communities of interest?An update on the CSU Pomology program was given at the 2018Western Colorado Horticultural Society's annual meeting in Grand Junction, CO. An Annual CSU Pomology Field day was organized in June 2018 with over 50 local growers attending. A CSU Pomology website was developed were all reports, presentations and updates are posted and shared with stakeholders through email updates. One of the most important services to our stakeholders is the peach floral bud weekly cold hardiness updates that are being posted to our CSU Pomology website and communicated with stakeholders through the Fruit Facts emailing list. Last dormant (2017/18) season 24 updates were posted. During the current dormant season 12updates have been posted so far. A pruning training workshop is being organized for January 2019 to inform and train tree fruit growers with the most research findings of this project. What do you plan to do during the next reporting period to accomplish the goals?Quality prediction models created using a NIR non-destructive sensor are going to be utilized over the next growing season (2019), to provide a deeper understanding of the effect of cultivar, tree height, nutrition management and crop load on peach fruit quality. Additionally, the same sensor will be utilized to study the effect of different pruning styles, of shoot size and fruit position in the canopy on peach fruit quality. Data on 'Suncrest', 'Sierra Rich', 'Cresthaven' and 'Red Haven' peach dormant bud acclimation, mid- winter, and bud break cold hardiness are being collected during the dormant season of 2018/19with Differential Thermal Analysis (DTA) and weekly updates on cold hardiness status of those cultivars are going to be posted in CSU Pomology web site. Data on tree growth, health, yield will be collected as in 2018.

Impacts
What was accomplished under these goals? Goal 1 Objective 1 Peach training systems trial A field study to compare peach training/canopy management systems, different rootstocks, and tree densities has been established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Red Haven trees grafted on St. Julien rootstock and O'Henry trees grafted on Krymsk 86 were planted in different distances among them in the rows in May 3, 2016. These trees were trained in Open Vase, Hex V, Quad V, Tall Spindle Axe (TSA), KAC-V and Bi- Axe in spring 2018. This experimental plot will be used as showcase site for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices. For this third leaf season (2018) trees were trained at final scaffold numbers and tree survival and growth data were collected. Sweet cherry training systems trial A field study to compare sweet cherry training/canopy management systems, different rootstocks, and tree densities has been established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Bing cherry trees grafted on Krymsk 6 and Gisela 6 and Skeena cherry trees grafted on Krymsk 6 and Gisela 6 were planted in different distances among them in the rows in May 4, 2016. These trees were trained in Upright Fruiting Offshoots (UFO), Super slender axes (SSA), Bi-Axe, Tall Spindle Axe (TSA) and Kym Green Bush (KGB) in spring 2018. This experimental plot will be used as showcase site for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices. For this third leaf season (2017) trees were trained at final architectures and tree survival and growth data collected were collected. Peach varieties trial A field study to evaluate different peach cultivars in western Colorado conditions was established in May 3 and 5, 2016 at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Glohaven/Lovell, Glowingstar/Lovell, Blushingstar/Lovell, Starfire/Lovell, Newhaven/Lovell Flamin Fury PF 19-007/Lovell, Flamin Fury PF 23/Lovell, Flamin Fury PF 24 Cold Hardy/Lovell, Red Haven/Lovell, August Lady/Hansen 536, Ryan Sun/Hansen 536 Red Haven/St. Julien and O'Henry/Krymsk 86 trees were planted in a completely randomized block design of 8 replicates. This experimental plot will be used as showcase site for workshops and field days as well as for research. Data collected in this third leaf season (2018) include tree growth, survival and cold hardiness using differential thermal analysis (DTA). Objective 2 Fruit internal quality prediction models have been successfully developed for 'Sierra Rich' and 'Cresthaven' peach cultivars that can estimate internal fruit quality [dry matter content (DMC) and soluble solids concentration (SSC)], and maturity [chlorophyll content (IAD)] through a hand-held non-destructive sensor (Felix F-750) that uses short-wave near infrared (NIR) spectrometry. Developed non-destructive models were used to further study the effect of fruit position in the canopy on fruit quality in collaboration with local commercial peach growers. In addition, these models were used to estimate internal quality on different peach cultivars to validate model capacity and extend the range of applicability of the developed technology. These models are going to be utilized to study in more detail the effect of crop load, rootstock, canopy management strategy (pruning styles and training systems), and soil profile on fruit quality both in WCRC-OM and in different commercial growers' blocks on the coming growing season of 2019. Objective 3 Effect of crop load on peach and apple fruit quality, tree physiology and dormant bud cold hardiness During the growing season of 2016 different crop load levels were achieved in 'Sierra Rich' and 'Cresthaven' peaches and 'Gala' apples by applying different thinning patterns (unthinned trees, heavy, commercial, and light crop load). Fruit growth, maturity and quality were monitored during the growing season with NIR and Vis/NIR non-destructive sensors with the models mentioned above. Fruit from different crop loads were assessed for internal and external quality and storage potential with destructive and non-destructive methods to investigate the effect of crop load on fruit harvest quality and postharvest storage potential. Results, showed that crop load reduced fruit quality and delayed fruit ripening in both apples and peaches. Postharvest performance of peaches and apples studied over the fall/winter season of 2016/17. Data on 'Sierra Rich' and 'Cresthaven' peach dormant bud acclimation and mid-winter cold hardiness are being collected during the dormant season of 2016/17 and will be collected over the next dormant season with Differential Thermal Analysis (DTA). This study didn't continue for 2017 and 2018 season due to spring frost which caused a crop reduction in peaches and apples. The crop/load thinning time series of experiments will continue in the season of 2019. Effect ofrootstockson peachfruit internal quality During the growing season of 2016, 2017 and 2018 'Red Haven' fruit coming from the 2009 Peach Rootstock Trial were utilized to create new internal quality (measured as DMC, SSC), and maturity [chlorophyll content (IAD)] models using a hand-held non-destructive sensor (Felix F-750) that uses short-wave near infrared spectrometry. These models were utilized to study the effect of the different rootstocks on fruit internal quality. Collectively, following this 3-season field study it has been demonstrated that tree vigor interferes with fruit internal quality. The more vigorous rootstocks reduced fruit DMC over the dwarfing rootstocks that produced fruit of superior internal qualities. Goal 2 See section 'How have the results been disseminated to communities of interest?'.

Publications

  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Minas, I.S., Tanou G., Molassiotis, A. 2018. Environmental and orchard bases of peach fruit quality. Scientia Horticulturae 235, 307-322.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Karagiannis, E., Michailidis M., Karamanoli, K., Lazaridou, A., Minas, I.S., Molassiotis, A. 2018. Postharvest responses of sweet cherry fruit and stem tissues revealed by metabolomic profiling. Plant Physiology and Biochemistry 127, 478-484.
  • Type: Websites Status: Published Year Published: 2018 Citation: Sterle, D., Minas I.S. 2018 Cold hardiness assessment of peach flower buds using differential thermal analysis (DTA) in western Colorado (dormant season 2017-18). 21 website updates posted at CSU Pomology website: https://minas.agsci.colostate.edu/tree-fruit-information/cold-hardiness.


Progress 10/01/16 to 09/30/17

Outputs
Target Audience:Scientific community, tree fruit growers, extension personnel and CSU students Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Fernando Blanco an exchange PhD student from CICYTEX, Spain was trained on the use of non-destructive sensors to study tree fruit growth and quality during the growing season of 2016. Research associates located in the WCRC-OM are now trained in the use of new technologies to estimate fruit quality as well as on new pruning/training techniques. How have the results been disseminated to communities of interest? An update on the CSU Pomology program was given at the 2017 Western Colorado Horticultural Society's annual meeting in Grand Junction, CO. For the first time an Annual CSU Pomology Field day was established with over 50 local growers attending. A CSU Pomology website was developed were all reports, presentations and updates are posted and shared with stakeholders through email updates. One of the most important services to our stakeholders is the peach floral bud weekly cold hardiness updates that are being posted to our CSU Pomology website and communicated with stakeholders through the Fruit Facts emailing list. Last dormant (2016/17) season 24 updates were posted. During the current dormant season 16 updates have been posted so far. What do you plan to do during the next reporting period to accomplish the goals? Quality prediction models created using a NIR non-destructive sensor are going to be utilized over the next growing season (2018), to provide a deeper understanding of the effect of crop load on peach fruit quality. Additionally, the same sensor will be utilized to study the effect of different pruning styles, of shoot size and fruit position in the canopy on peach fruit quality. Data on 'Suncrest', 'Sierra Rich', 'Cresthaven' and 'Red Haven' peach dormant bud acclimation, mid- winter, and bud break cold hardiness are being collected during the dormant season of 2017/18 with Differential Thermal Analysis (DTA) and weekly updates on cold hardiness status of those cultivars are going to be posted in CSU Pomology web site. Data on tree growth, health, yield will be collected as in 2017.

Impacts
What was accomplished under these goals? Goal 1 Peach training systems trial A field study to compare peach training/canopy management systems, different rootstocks, and tree densities were established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Red Haven trees grafted on St. Julien rootstock and O'Henry trees grafted on Krymsk 86 were planted in different distances among them in the rows in May 3rd of 2016. These trees are going to be trained in Open Vase, Hex V, Quad V, Tall Spindle Axe (TSA), KAC-V and Bi-Axe. This experimental plot will be used as showcase site for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices. Data collection will include tree-growth, date of bloom, date of ripening, yield, fruit quality and cold hardiness. For this second leaf season (2017) trees were prepared for training and tree survival and growth data collected. Sweet cherry training systems trial A field study to compare sweet cherry training/canopy management systems, different rootstocks, and tree densities were established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Bing cherry trees grafted on Krymsk 6 and Gisela 6 and Skeena cherry trees grafted on Krymsk 6 and Gisela 6 (were planted in different distances among them in the rows in May 4rd of 2016. These trees are going to be trained in Upright Fruiting Offshoots (UFO), Super slender axes (SSA), Bi-Axe, Tall Spindle Axe (TSA) and Kym Green Bush (KGB). This experimental plot will be used as showcase site for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices. Data collected will include tree-growth, date of bloom, date of ripening, yield, fruit quality and cold hardiness. For this second leaf season (2017) training of most of the training systems performed and tree survival and growth data collected. Peach varieties trial A field study to evaluate different peach cultivars in western Colorado conditions was established in May 3rd and 5th of 2016 at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Glohaven/Lovell, Glowingstar/Lovell, Blushingstar/Lovell, Starfire/Lovell, Newhaven/Lovell Flamin Fury PF 19-007/Lovell, Flamin Fury PF 23/Lovell, Flamin Fury PF 24 Cold Hardy/Lovell, Red Haven/Lovell, August Lady/Hansen 536, Ryan Sun/Hansen 536 Red Haven/St. Julien and O'Henry/Krymsk 86 trees were planted in a completely randomized block design of 8 replicates. This experimental plot will be used as showcase site for workshops and field days as well as for research. Data collected will include tree-growth, date of bloom, date of ripening, yield, fruit quality and cold hardiness. Goal 2 Models developed for 'Sierra Rich' and 'Cresthaven' peach cultivars that can estimate internal fruit quality [dry matter content (DMC) and soluble solids concentration (SSC)], and maturity [chlorophyll content (IAD)] through a hand-held non-destructive sensor (Felix F-750) that uses short-wave near infrared (NIR) spectrometry were used to further study the effect of fruit position in the canopy on fruit quality in collaboration with local commercial peach growers. In addition, these models were used to estimate internal quality on different peach cultivars to validate model capacity and extend the range of applicability of the developed technology. These models are going to be utilized to study in more detail the effect of crop load, rootstock, canopy management strategy (pruning styles and training systems), and soil profile on fruit quality both in WCRC- OM and in different commercial growers' blocks on the coming growing season of 2018. Goal 3 Effect of crop load on peach and apple fruit quality, tree physiology and dormant bud cold hardiness During the growing season of 2016 different crop load levels were achieved in 'Sierra Rich' and 'Cresthaven' peaches and 'Gala' apples by applying different thinning patterns (unthinned trees, heavy, commercial, and light crop load). Fruit growth, maturity and quality were monitored during the growing season with NIR and Vis/NIR non-destructive sensors with the models mentioned above. Fruit from different crop loads were assessed for internal and external quality and storage potential with destructive and non-destructive methods to investigate the effect of crop load on fruit harvest quality and postharvest storage potential. Results, showed that crop load reduced fruit quality and delayed fruit ripening in both apples and peaches. Postharvest performance of peaches and apples studied over the fall/winter season of 2016/17. Data on 'Sierra Rich' and 'Cresthaven' peach dormant bud acclimation and mid-winter cold hardiness are being collected during the dormant season of 2016/17 and will be collected over the next dormant season with Differential Thermal Analysis (DTA). This study didn't continue for 2017 season due to spring frost which caused a 30-50% crop reduction in peaches and around 20-30% in apples. The crop/load thining time series of experiments will continue in the season of 2018.

Publications

  • Type: Journal Articles Status: Awaiting Publication Year Published: 2018 Citation: Minas IS*, Tanou G, Molassiotis A. Environmental and orchard bases of peach fruit quality. Invited Review article for a Special Issue in Scientia Horticulturae 2018
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Minas IS, Blanco Cipollone F. Non-destructive assessment of the effect of crop load and canopy position on peach fruit harvest maturity and internal quality using near infrared spectroscopy. 9th International Peach Symposium, Bucharest, Romania. July 2, 2017
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Minas I, Sterle DG, Caspari HW. Understanding the environmental bases for cold hardiness and cold damage in peach floral buds using differential thermal analysis. 9th International Peach Symposium, Bucharest, Romania. July 2, 2017
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Karagiannis E, Tanou G, Samiotaki M, Michailidis M, Diamantidis G, Minas IS, Molassiotis A. Comparative Physiological and Proteomic Analysis Reveal Distinct Regulation of Peach Skin Quality Traits by Altitude. Frontiers in Plant Science 2016, 7, 1689.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Tanou G, Minas IS, Scossa F, Belghazi M, Xanthopoulou A, Ganopoulos I, Madesis P, Fernie A, Molassitis A. Exploring priming responses involved in peach fruit acclimation to cold stress. Scientific Reports 2017, 7, 11358.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Minas I. CSU Pomology Research Program Update. Western Colorado Horticultural Society 2017 Annual Meeting, Grand Junction, CO. January 19, 2017


Progress 07/01/16 to 09/30/16

Outputs
Target Audience:Scientific community and Fruit growers Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Fernando Blanco an exchange PhD student from CICYTEX, Spain was trained on the use of non-destructive sensors to study tree fruit growth and quality during the growing season of 2016. How have the results been disseminated to communities of interest?An update on the CSU Pomology program was given at the 2017 Western Colorado Horticultural Society's annual meeting in Grand Junction, CO. What do you plan to do during the next reporting period to accomplish the goals?The above-mentioned models that estimate DM, SSC, FF and IAD and were created using a NIR non-destructive sensor are going to be utilized over the next growing season (2017), to provide a deeper understanding of the effect of crop load on peach fruit quality. Additionally, the same sensor will be utilized to study the effect of different pruning styles, of shoot size and fruit position in the canopy onpeach fruit quality. Data on 'Sierra Rich' and 'Crest Haven' peach dormant bud acclimation, mid-winter, and bud break cold hardiness are being collected during the dormant season of 2016/17 and will be collected over the next dormant season with Differential Thermal Analysis (DTA). Data on tree growth, health, yield will be collected as in 2016.

Impacts
What was accomplished under these goals? Goal 1 Peach training systems trial A field study to compare peach training/canopy management systems, different rootstocks, and tree densities were established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. One hundred twenty trees of Red Haven grafted on St. Julien rootstock and 120 O'Henry trees grafted on Krymsk 86 were planted in different distances among them in the rows in May 3rd of 2016. These trees are going to be trained in Open Vase (distance among trees in the row: 12'), Hex V (10'), Quad V (8'), Tall Spindle Axe (TSA) (5'), KAC-V (5') and Bi-Axe (5'). The peach trees were planted in a completely randomized block design of 3-tree plots per cultivar/training system combination. This experimental plot will be used as showcase site for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices (summer pruning, fertigation, foliar nutrition etc.). Data collected will include tree-growth, date of bloom, date of ripening, yield, fruit quality and cold hardiness Sweet cherry training systems trial A field study to compare sweet cherry training/canopy management systems, different rootstocks, and tree densities were established at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Sixty Bing cherry trees grafted on Krymsk 6 and Gisela 6 (30 and 30 trees, respectively) and 60 Skeena cherry trees grafted on Krymsk 6 and Gisela 6 (30 and 30 trees, respectively) were planted in different distances among them in the rows in May 4rd of 2016. These trees are going to be trained in Upright Fruiting Offshoots (UFO, 5'), Super slender axes (SSA, 3'), Bi-Axe (5'), Tall Spindle Axe (TSA, 5'), Kym Green Bush (KGB, 5'). The cherry trees were planted in a completely randomized block design of 3-tree plots per cultivar/training system combination. This experimental plot will be used as showcase site for workshops and field days as well as for research. In addition to the main objective of this study several other research experiments will be conducted to include different cultural practices (summer pruning, fertigation, foliar nutrition etc.). Data collected will include tree-growth, date of bloom, date of ripening, yield, fruit quality and cold hardiness. Peach varieties trial A field study to evaluate different peach cultivars in western Colorado conditions was established in May 3rd and 5th of 2016 at Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO. Glohaven/Lovell, Glowingstar/Lovell, Blushingstar/Lovell, Starfire/Lovell, Newhaven/Lovell Flamin Fury PF 19-007/Lovell, Flamin Fury PF 23/Lovell, Flamin Fury PF 24 Cold Hardy/Lovell, Red Haven/Lovell, August Lady/Hansen 536, Ryan Sun/Hansen 536 Red Haven/St. Julien and O'Henry/Krymsk 86 trees were planted in a completely randomized block design of 8 replicates. This experimental plot will be used as showcase site for workshops and field days as well as for research. Data collected will include tree-growth, date of bloom, date of ripening, yield, fruit quality and cold hardiness. Goal 2 'Sierra Rich' and 'Cresthaven' fruit coming from different blocks of the Colorado State University's WCRC-OM experimental orchard in Grand Junction, CO, were utilized to create new internal quality [measured as dry matter (DM) and soluble solids concentration (SSC)], and maturity [measured as fruit firmness (FF) and chlorophyll content (IAD)] models using a hand-held non-destructive sensor (Felix F-750) that uses short-wave near infrared spectrometry. The models created using this non-destructive sensor were validated independently and the resulting regression analysis provided a linearity of 0.9748, 0.9866, and 0.9414 (Sierra Rich) and 0.9442, 0.9039, 0.9390 (Cresthaven) (R2) for DM, SSC, and IAD, respectively. FF model didn't show a significant linearity in both cultivars tested. These models are going to be utilized to study the effect of crop load, rootstock, canopy management strategy (pruning styles and training systems), and soil profile on fruit quality both in WCRC-OM and in different commercial growers' blocks on the coming growing season of 2017. Goal 3 Effect of crop load on peach and apple fruit quality, tree physiology and dormant bud cold hardiness During the growing season of 2016 different crop load levels were achieved in 'Sierra Rich' and 'Cresthaven' peaches and 'Gala' apples by applying different thinning approaches (unthinned trees, hand-thinned to leave 2, 6, 12'' spacing among fruit per shoot, and only in the case of apples chemically thinned and corrected with hand thinning to 6'' among fruit. Fruit growth, maturity and quality were monitored during the growing season with NIR and Vis/NIR non-destructive sensors with the models mentioned above. Fruit from different crop loads were assessed for internal and external quality and storage potential with destructive and non-destructive methods to investigate the effect of crop load on fruit harvest quality and postharvest storage potential. Results, showed that crop load reduced fruit quality and delayed fruit ripening in both apples and peaches. Postharvest performance of peaches and apples is being studied over the fall/winter season of 2016/17. Data on 'Sierra Rich' and 'Cresthaven' peach dormant bud acclimation and mid-winter cold hardiness are being collected during the dormant season of 2016/17 and will be collected over the next dormant season with Differential Thermal Analysis (DTA).

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