Source: N Y AGRICULTURAL EXPT STATION submitted to
BREEDING DESIGNER APPLE ROOTSTOCKS TO MATCH NUTRIENT PARAMETERS UNDER ORGANIC MANAGEMENT
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
OTHER GRANTS
Reporting Frequency
Annual
Accession No.
1027438
Grant No.
2021-51106-35767
Cumulative Award Amt.
$445,976.00
Proposal No.
2021-02891
Multistate No.
(N/A)
Project Start Date
Sep 1, 2021
Project End Date
Aug 31, 2024
Grant Year
2021
Program Code
[113.A]- Organic Agriculture Research & Extension Initiative
Project Director
Robinson, T. L.
Recipient Organization
N Y AGRICULTURAL EXPT STATION
(N/A)
GENEVA,NY 14456
Performing Department
Horticulture
Non Technical Summary
Organic apple production in the Eastern US is small and is mostly based on existing rootstocks, which are susceptible to fire blight which creates a very high risk of infection and tree death.The incorporation of disease-resistant rootstocks would greatly reduce the risk. New resistant, dwarfing rootstocks also allow high-density orchards, which begin production in the second or third leaf can achieve 50% higher yields than traditional orchards. This project will develop and then extend to Eastern organic apple growers information on the best rootstock options for various soils and climate situations.The results of the project will be packaged into an online, smart rootstock recommendation system that will allow organic apple growers to input the specifics of their future orchard and receive a specific recommendation of the best rootstock choice considering climate, soil, cultivar and location. The project will support OREIGoal 1. Facilitating the development and improvement of organic agriculture production, breeding, and processing methods; Goal 4. Determining desirable traits for organic commodities; and Goal 6. Conducting advanced on-farm research and development that emphasizes observation of, experimentation with, and innovation for working organic farms, including research relating to production, marketing, food safety, socioeconomic conditions, and farm business management.Overall, we expect this project to lead to increased commercial organic apple production in the Eastern USA to meet the increasing demand for locally produced organic apples.
Animal Health Component
50%
Research Effort Categories
Basic
10%
Applied
50%
Developmental
40%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2051110108130%
2051110102070%
Knowledge Area
205 - Plant Management Systems;

Subject Of Investigation
1110 - Apple;

Field Of Science
1081 - Breeding; 1020 - Physiology;
Goals / Objectives
The project will support OREI Goal 1. Facilitating the development and improvement of organic agriculture production,Goal 4. Determining desirable traits for organic commodities; and Goal 6. Conducting advanced on-farm research and development The long-term goals of this project are:Identify and deploy improved apple rootstocks with a range of vigor levels among newly released and unreleased advanced test selections from the Geneva apple rootstock breeding program for organic apple growers that will provide high productivity, high fruit quality and resistance to several important diseases and climate events affecting organic apple production.Determine rootstock effects related fruit mineral profile under organic management especially effects on nutrients that affect fruit quality and susceptibility to storage disorders.Develop and deploy an online smart rootstock recommendation system that considers the location, soil, and cultivar of the new orchard to then provide rootstock recommendations for organic apple growers.
Project Methods
We willconduct field research over three seasons in two dedicated organic apple research orchards at Cornell's Geneva Experiment Station and at Singer Farms in Appleton, NY. At Geneva we will conduct replicated experiments on rootstock performance, and rootstock influence on fruit quality, fruit mineral profile and fruit storage disorders on three apple cultivars (Modi, a disease resistant variety, Honeycrisp and Ruby Frost, both disease susceptible varieties).We will also establish one new experimental plot at Geneva in 2020where we will evaluate the performance of 11 new disease resistant apple rootstocks with Snapdragon variety for growth and production performance.These rootstocks will also be monitored at the DNA level to validate the effectiveness of DNA markers for improving rootstock performance under organic management.Year 1 (2021)Evaluate new rootstock in organic apple production in trial at Geneva and Singer Farms in Appleton NY. Measure fruit mineral nutrient profile of new rootstocks and correlate them with fruit size, fruit quality and fruit storage disorders especially bitter pit.Year 2 (2022)Conduct rootstock evaluations of new rootstocks for organic production at Geneva and Singer Farms in Appleton NY. Measure fruit mineral nutrient profile of new rootstocks and correlate them with fruit size, fruit quality and fruit storage disorders especially bitter pit. Begin the development of an online smart rootstock decision tool for organic apple production in the Eastern US.Year 3 (2023)Conduct rootstock evaluations of new rootstocks for organic production at Geneva and Singer Farms in Appleton NY. Measure fruit mineral nutrient profile of new rootstocks and correlate them with fruit size, fruit quality and fruit storage disorders especially bitter pit. Conduct a grower workshops with NOFA-NY on rootstocks and cultivars (fall). Finish the development and launch the online smart rootstock decision tool for organic apple production in the Eastern US. Compile final report.We will conduct our research in four dedicated organic apple research plots at Cornell's Geneva Experiment Station and one plot at Singer Farms in Appleton NY.Objective 1:We will compare the horticultural performance of new disease resistant Geneva® rootstocks on tree growth and yield in 5 field plots listed above. We will evaluate tree growth, survival, yield and fruit quality each year from 2021-2023. Tree health will be monitored throughout the trial. Dead trees and possible reason for loss will be recorded each year at the time when growth measurements are taken. The incidence of rootstock suckering will also be recorded during this study. From our field data we will develop a set of recommended rootstocks for organic growers that have sufficient growth to fill the allotted space (~3 ft) by the end of the third year, while producing high yields in the first 5-10 years.Objective 2We will evaluate nutrient profiles in the fruit as affected by rootstock and then correlate nutrient levels to yield, fruit size, quality and fruit disorders. Ten randomly selected fruits distributed throughout the tree canopy will be harvested 120 days after bloom on three replicates of each rootstock genotype from of each of the 5 field trials mentioned above.The ten sampled fruits will be peeled (lower half of the fruit -calyx end) and the peels will be bulked into one sample per tree for analysis.Fruit peels will be oven dried, ground into powder and shipped to the Great Lakes analysis lab for mineral analysis of several macro- and micro-mineral nutrients via inductively coupled plasma optical emission spectrometry.Leaf K and Ca concentration of the fruit from one field trial (Geneva 'Modi' experiment) will be measured with a hand held Xraynutrient analyzer instrument.Soil samples will be collected from 6 field locations from all research plots and will be analyzed for nutrients after modified Morgan extraction at Agro-One, Ithaca, NY. Fruit nutrient concentration values will be tabulated and analyzed with SAS and JMP Pro statistical software packages; the rootstock genotype will be treated as the main effect in a randomized complete block analysis. Rootstock genotype means will be used in a multivariate analysis to generate correlation matrices and two-way similarity cluster diagrams based on genotype and variable similarities.We will use those means to validate the effect of the presence/absence of specific DNA markers linked to nutrient uptake and other organic friendly root traits.Relevant validated markers will be used to query a larger rootstock pool to search for new material to test under organic management.Objective 3We will compile the information from our field trials to understand their productivity performance in relation to innate nutrient uptake potential.From this information we will first develop more accurate nutrient management recommendations for organic growers in the Northeast. We will then use this information to develop an online smart rootstock selection tool that will consider soil type, scion cultivar vigor, climate vigor and grower nutrient input plan to select/recommend the best rootstocks for each new organic orchard.To develop the selection tool, we will categorize all the soil types in NY State into vigor classes based on nitrogen supplying power. For growers outside of NY State we will request that they input a soil vigor. We will also categorize scion varieties into vigor classes.We will develop a climate vigor index to categorize growing locations based on heat-unit accumulation during the growing season. Lastly we will allow growers to input the nitrogen fertilization plant they will implement.These assessments to vigor will be used to then pair a Geneva® rootstock with sufficient vigor that will perform well under those conditions.For this project we will develop the smart rootstock selection tool for the Eastern USA but we plan to extend this tool to other production areas if cooperators from other states are interested.

Progress 09/01/21 to 08/31/24

Outputs
Target Audience:Organic apple growers in the eastern USA Changes/Problems:In the spring of 2022, a severe outbreak of fire blight was experienced across NY State. One of the research plots for this project was severely affected by fire blight with the loss of some trees. However, we were able to continue with the experiment and concluded that trial in 2024 and are in the process of publishing the final results this winter. We had planned a field day at this experiment but with the fire blight damage we decided it would not be helpful to bring organic growers to the site. Thus, we chose to publish our project results in the Fruit Quarterly Magazine and give our rootstock recommendations in print rather than at a field day. What opportunities for training and professional development has the project provided?Through this project we have trained 1 graduate student (MS) (Julie Cardon) who completed her degree in July of 2024. Her thesis title (Characterizing rhizosphere microbes and metabolites of rootstocks that differ in their resistance to apple replant disease.)is direclty related to this project. We have also partially completed the training of 1 PhD graduate student (Davis Upchurch) who is studying virus effects on rootstock performance. This project has contributed to the post doctoral training of onePost Doctoral Researcher (Brian Lawrence) in our program. How have the results been disseminated to communities of interest?1. We have published recommendations from this project for organic apple growers in the Fruit Quarterly Magazine in 2024. This magazine is sent to all apple growers in NY and MI and is available to apple growers world wide online. 2. We have developed a website with the characteristics of the Geneva rootstocks that will help all apple growers chose the best rootstock for their situation. 3. While online tools can provide an initial idea of what rootstock choices to make, the investigators had an additional idea on how to provide long lasting information to organic apple growers in the North-East. Perhaps the best way for an organic apple grower to know what rootstocks work best is to experience them first-hand in their specific locations. Therefore, after the first two years of nutrient analysis data we identified some of the rootstock choices the best fire blight and replant disease tolerant rootstocks (G.257, G.484, G.66, G.41, G.935 and G.969) which also featured some advantageous nutrient uptake profiles and combined them with some of the best scab resistant scion varieties (requiring less sprays) to make apple trees that could be distributed to organic apple growers to test them. The process of making trees in the nursery lasted two years (we had to grow the rootstocks first - year 1 - and then graft the scion and grow the trees - year 2) The scions that were chosen were Triumph (https://mnhardy.umn.edu/triumph) a scab resistant apple bred by the University of Minnesota and Story® also known as Innored (https://acnursery.com/product/story-inored-cv-pppp22794/) another high quality scab resistant apple. We had about 2,000 trees (1,000 for each scion variety) which were propagated on 7 different apple rootstocks. These trees were distributed in the Spring-Summer of 2024 to 12 different organic growers in four different states including NY, MI, ME, VT and very different size and type operations including multi-generation family farms, Amish, large companies with organic operations, and scientific advisors. What is characteristic about communities that work with organic principles is that they support each other in online forums and by word of mouth. The planting of these trees will likely provide more localized, experience-based communications. While the duration of this grant is over, the impact of these plantings will last for many years to come. 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 report: In the planning phase of establishing an organic orchard, growers need to make some critical decisions with regards to what type of scion variety is going to be planted and just as important what type of rootstock is going to support the growth and production of that variety. While the choice of scion variety is not part of this work, it cannot be overlooked as the whole tree (scion and rootstock) is what is finally deployed and starting up with a disease resistant scion (apple scab, fire blight, bacterial spot etc.) will certainly enhance the profitability of the operation. As far as the choice of rootstock there are some important considerations that have become evident because of this research: 1.Disease resistant apple rootstocks with generally outperform traditional apple rootstocks when it comes to tree survival and productivity. The North-East is endemic to one of the most devastating apple diseases called fire blight caused by the bacterium Erwinia amylovora. In our plantings we have witnessed scions that were severely impacted by this disease and yet when the rootstocks were of resistant type the whole tree did not die and was able to be recovered in successive years. Other soil diseases related to replant disease were also important as we could see the difference between sensitive and susceptible rootstocks in the way they grew and yielded fruit. 2.More vigorous trees that are also precocious are desired in organic production. Apple trees under organic management are challenged by weed competition in the root zone around the tree. This competition will decrease the size and productivity of apple trees and many organic apple growers have resorted to substituting dwarfing precocious rootstocks that are sensitive to this competition with vigorous, non-precocious (productive) rootstocks to overcome this weakness. As it turns out, this is a very poor choice because it ends up delaying production of the orchard by several years and reducing apple yields favoring the production of unfruitful wood. Our experiments showed that newly released rootstocks such as G.484, G.257 and G.890 will provide the extra growth needed to support a very productive orchard when compared to traditional choices such as M.7, MM.111, B.118 and MM.106. Over the long-term live of an organic orchard even small increases in the productivity per tree translates in huge gains in profitability. 3.More resilient rootstocks to adverse climate events can be deployed in organic apple orchards. While this project did not focus on adverse climatic events and the length of the grant period (3-4) years did not permit to observe once in a decade events it still provided some insight into climatic considerations that organic apple grower should take into account when choosing a rootstock. Adverse climatic events that affect rootstocks include: excessive rain and flooding, extreme drought periods, early winter cold snaps, extreme mid-winter cold, mid-winter warming period followed by sudden cold snap. There are rootstocks (G.41, G.935, G.202) that seem to survive long periods of flooding when compared to the traditional rootstocks (M.9, B.9, M.26, and M.7). This tendency is likely partially due to tolerance to crown rot caused by phytophthora species which attacks rootstock tissues weakened by the lack of oxygen. Tolerance to mid-winter and early winter cold events has been described in apple rootstocks G.41, G.202, G.935 and G.214. Tolerance to drought by apple rootstocks is a very complex trait and is still being investigated. 4.Fruit quality characters such as fruit size, color, maturity and internal quality can be drastically influenced by apple rootstocks under organic management. Similarly to what happens under conventional management, the choice of apple rootstocks has proven to increase the average size of fruit (G.41, G.257 or G.814) while maintaining high production. Apple rootstock G.11 has been shown to increase maturity and decrease time to pick. Apple rootstocks G.214 and G.969 have been proven to decrease bitter pit of apples significantly. Overall, under goal 1 we have determined that several Geneva® apple rootstocks are a better choice for organic apple growers, where the ultimate choice is dependent on several factors that are outlined in goal 3. Goal 2 report: The process of determining rootstock effects on nutrient uptake under organic management involved collecting, processing and analyzing over 5,200 leaf and fruit samples over 4 years. The results were summarized in a few presentations to apple growers and scientific conference and two manuscripts (Apple rootstocks affect mineral nutrient uptake in organic orchards - presented at the Mineral Nutrition of Fruit Trees Symposium, International Society for Horticultural Science) which compared the results from field trials in three different locations over several years. We monitored the content of phosphorous (P), potassium (K), calcium (Ca), sulfur (S), iron (Fe), manganese (Mn), and copper (Cu) in leaves and fruit of three experimental orchards using Energy-Dispersive X-ray Fluorescence (XRF) for two seasons (2022-2023). Two of the plantings (Geneva and Ithaca, NY) are part of the 2015 organic NC-140 trial and feature 11 commercial rootstocks grafted with the scab resistant scion cultivar 'Modi®', whereas the third trial established in 2013 in Albion, NY features 18 commercial and experimental rootstocks grafted with 'Crimson Crisp'. In Geneva, the 2022 and 2023 XRF data showed that Geneva®(G) 969, G.41, G.935, and G.222 contained greater leaf S which has been shown to have a strong correlation with leaf N concentration. In Ithaca, the 2022 and 2023 XRF data showed that G.890 had consistently higher S, P, and K levels. Rootstocks G.11 and G.214 displayed lower levels of S in both locations and both years. Other nutrient levels were somewhat inconsistent between locations and years in the NC-140 trials. In the Albion organic trial rootstocks, G.484, G.890, G.222, and CG.5030 displayed higher levels of leaf P and S (measured by ICP in 2014 and 2016). Rootstock CG.4003 displayed consistently higher levels of Ca in leaves and fruit in the XRF data, as well as the ICP data. Multivariate analysis using mean ICP and XRF leaf nutrient data found significant similarities for Ca and K perhaps validating the usefulness of the XRF instrument to calculate rootstock influenced K/Ca ratios. While seven rootstocks were common at all experimental locations, the interaction of different scion cultivars, ground floor management, soil type, and fertilizer applications may have contributed to the low levels of correlation among other nutrients. Due to their overall nutrient use efficiency, G.890, G.484, G.222, and perhaps G.935 are well suited for organically managed orchards. Goal 3 This goal is reported below in the extension of results section.

Publications

  • Type: Peer Reviewed Journal Articles Status: Published Year Published: 2024 Citation: Al Farqani, A., Cheng, L., Robinson, T.L. and Fazio, G. 2024. Effect of soil solution pH on root architecture and dynamics of root distribution of four apple rootstocks grown in an aeroponics nutrient misting system. Front. Plant Sci. 15:1351679. doi: 10.3389/fpls.2024.1351679
  • Type: Theses/Dissertations Status: Published Year Published: 2024 Citation: Cardon, J. 2024. Characterizing rhizosphere microbes and metabolites of rootstocks that differ in their resistance to apple replant disease. M.S. Thesis, Cornell University, Ithaca, NY.
  • Type: Peer Reviewed Journal Articles Status: Published Year Published: 2024 Citation: Gonzalez, L., Ho, S-T, B.J. Rickard, G. Fazio, G. Reig, J. Lordan, S.A. Hoying, M.J. Fargione, M. Miranda Sazo, T.L. Robinson. 2024. Estimated Economic Impacts of Fire Blight on Long-Term Orchard Economic Performance with Susceptible and Disease Resistant Rootstocks. Scientia Hort. 337 (2024) 113478
  • Type: Peer Reviewed Journal Articles Status: Published Year Published: 2024 Citation: Ho, S.-T., L. Gonzalez, B.J. Rickard, G. Reig, J. Lordan, G. Fazio, S.A. Hoying, M. Fargione, M. Miranda Sazo and T.L. Robinson. 2024. Effects of Cultivar, Training System and Rootstock on Long-term Economic Performance of Apple Orchards in the Northeastern U.S. Scientia Hort. 332, 2024, 113194.
  • Type: Other Journal Articles Status: Published Year Published: 2024 Citation: Fazio, G., G. Peck, T. Robinson. 2024. Rootstocks for organic apple orchards. Fruit Quarterly 32(3):4-7.
  • Type: Other Journal Articles Status: Published Year Published: 2024 Citation: Robinson, T.L., L. Cheng, G. Fazio, C.B. Watkins, M. Miranda Sazo, L. Gonzalez, B. Lawrence, Craig Kahlke, Mike Basedow, P. Francescatto, A. Al Farqani and S. Lopez. 2024. Management of Honeycrisp apple trees for maximum sustained yield and minimal bitter pit. Fruit Quarterly 32(1): 4-10.
  • Type: Other Journal Articles Status: Published Year Published: 2024 Citation: Robinson, T.L., L. Gonzalez Nieto, S.-T. Ho, B.J. Rickard, G. Reig, J. Lordan, G. Fazio, S.A. Hoying, M.J. Fargione, M. Miranda Sazo. 2024. Apple orchard economics: Effects of cultivar, planting density and rootstock. Fruit Quarterly 32(2): 4-11.
  • Type: Other Journal Articles Status: Published Year Published: 2024 Citation: Robinson, T.L., Gonzalez, L., Ho, S-T, B.J. Rickard, G. Fazio, G. Reig, J. Lordan, S.A. Hoying, M.J. Fargione, M. Miranda Sazo. 2024. Economic impact of fire blight with susceptible and resistant apple rootstocks. Fruit Quarterly 32(3):15-20.
  • Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2024 Citation: Fazio, G., G. Peck, T. Robinson. 2024. Apple rootstocks affect mineral nutrient uptake in organic orchards. Acta Hortic. (in press)
  • Type: Conference Papers and Presentations Status: Published Year Published: 2024 Citation: Cardon, J., Thies, J., Peck, G., Fazio, G., Robinson, T. 2024 Apple Rootstocks Affect Soil Rhizosphere Microbial Communities and Root Exudate Composition HortScience 59(9) Supplement p423 (Abstr.)
  • Type: Websites Status: Published Year Published: 2024 Citation: https://ctl.cornell.edu/wp-content/uploads/2024/08/Geneva-Rootstocks-Comparison-Chart_Web_Updated-8-2024_new.pdf


Progress 09/01/22 to 08/31/23

Outputs
Target Audience:Organic apple growers in the eastern USA Changes/Problems:A severe spring frost in May 2023 severly reduced the crop in the organic rootstock plot planted in 2015. What opportunities for training and professional development has the project provided?This project has given opportunities so far for 2graduate students (Julie Cardon and Davis Upchurch) whose thesesareon apple rootstock performance in organic management systems and soil microflora communities associated with each rootstock. One post doctoral researcher (Luis Gonzalez) has also been a part of the organic rootstock trial planted in 2015. How have the results been disseminated to communities of interest?In 2023the project leaders gave 2presentations to apple grower groups to disseminate the results of this project. We have also published 1articles in a natinal grower magazine about our work on rootstocks for organic apple growers. We have also released 3 new apple rootstocks that will be useful to organic apple growers in the next 10 years. What do you plan to do during the next reporting period to accomplish the goals?Next year we will study soil microflora as influenced by rootstock genotype in organic soils. We will also study root exudates from different rootstock genotypes. We will also study molecular markers of rootstock traits associated with high performance in organic management sustems.

Impacts
What was accomplished under these goals? Objective 1. An organic apple rootstock trial was conducted at Geneva NY. Tree size (TCSA) after 9 years reflects 5 groups of vigor: with G.16 and G.222 being the most dwarfing stocks; G.969, G.11, G.214, and G.935 slightly more vigorous; G.41 and M.9 were more vigorous; a semi-dwarfing group of G.202 and G.30; and finally, a semi-vigorous stock of G.890. TCSA increment roughly followed stock vigor. In 2023, G.16, G.935 and G.890 all had the most suckers on average (>4). Tree survival after 9 growing seasons was lowest for G.16 followed by G.935. Yield in 2023 was severely reduced due to frost damage in May 2023.Since yield was extremely low in 2023, 10-year cumulative measurements were similar to 2022, with the greatest cumulative yield with G.890 followed by G.41, G.30 and G.214. The lowest cumulative yield was with G.222 and G.16. Cumulative yield efficiency was higher with G.16 followed by G.214, G.11, G.935, and G.41 (> 2.0 kg/cm2 TCSA). After 9 growing seasons, G.935 and G.41 are promising rootstocks for organic production of Modi apple in a high-density system. For a medium density system, G.890 has shown good promise. A new rootstock trial was planted in a certified organic site at the Geneva experiment station in the spring of 2022. The trial compares 15 different rootstocks in a replicated design. In both 2023we sampled the soil adhering to the roots of these trees for DNA extraction in order to characterize both bacterial and fungal microorganisms in the rhizosphere of the rootstocks in our research. We also established an aeroponic greenhouse trial to sample rhizodeposits from 6 of the rootstocks used in the orchard trial, with the aim of characterizing plant metabolites which are exuded from roots with untargeted HPLC/LCMS. Objective 2. We have measured the effect of rootstock on mineral concentration in the peel of 'Honeycrisp' in 2 plots in NY State (Geneva 2010 Honeycrisp plot and Geneva 2014 Honeycrisp plot). We correlated the K/Ca ratio in the fruit peel) and bitter pit of Honeycrisp apple (Robinson and Fazio, 2022). The results of these studies support our earlier results that showed rootstock genotype has a large influence on bitter pit incidence and on the fruit nutrient levels of the peel (Fazio et al., 2019). In these studies, we have confirmed that B.9 in most cases has low bitter pit incidence. We have also identified several new Geneva® rootstocks which have low bitter pit incidence (G.214, G.969, G.935 and G.65) and other rootstocks that have high bitter pit incidence (G.210 and M.7). We are in the process of writing several research articles to summarize and extend our information on rootstocks and mineral nutrient profiles.

Publications

  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Bradshaw, T., Autio,W., Blatt, S., Clements, J., Einhorn, T., Elkins, R., Fallahi, E., Francescatto, P., Lordan, J., Minas, I., Peck, G., Robinson, T. and Yao S.. 2023. Performance of Modi� apple trees on several Geneva rootstocks managed organically: Five-year results from the 2015 NC-140 Organic Apple Rootstock Trial. Journal of the American Pomological Society 77 (1):14-27.
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2023 Citation: Ho, S.-T., L. Gonzalez, B.J. Rickard, G. Reig, J. Lordan, G. Fazio, S.A. Hoying, M. Fargione, M. Miranda Sazo and T.L. Robinson. 2023. Effects of Cultivar, Training System and Rootstock on Long-term Economic Performance of Apple Orchards in the Northeastern U.S. Scientia Hort. (In press)
  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Gonzalez, L., G. Reig, J. Lordan, M. Miranda Sazo, S.A. Hoying, M.J. Fargione, G.H. Reginato, D.J. Donahue, P. Francescatto, E. Casagrande, G. Fazio, T.L. Robinson. 2022. Long-term effects of rootstock and tree type on the economic profitability of Gala, Fuji and Honeycrisp orchards performance. Scientia Horticulturae 318, 2023, 112129, https://doi.org/10.1016/j.scienta.2023.112129.
  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Fazio G, Mazzola M, Zhu Y. 2023. Genetic analysis of resistance to pythium ultimum a major component of replant disease in apple rootstocks. Journal American Pomological Society. 77:28-37.
  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Emeriewen OF, Reim S, Richter K, W�hner T, Flachowsky H, Aldwinckle H, Peil A, Fazio G. 2023. The fire blight resistance qtl on lg7 of malus x robusta 5 is not dependent on the avrrpt2ea 156 s/c amino acid switch. Journal of Plant Pathology.8.
  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Fazio, G. and T. Robinson. 2023. New releases from the Geneva� apple rootstock breeding program. Fruit Quarterly 31:(1):29-33.
  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Londo, J.P., L. Gonzalez, and T.L. Robinson. 2023. Characterizing Cold Hardiness Dynamics in Apple Rootstocks. Fruit Quarterly 31:(1):4-7.


Progress 09/01/21 to 08/31/22

Outputs
Target Audience:Organic apple growers in the eastern USA Changes/Problems:In 2021 after we had submitte this proposal a severe fire blight epidemic killed one of the organic apple rootstock trials we had planned to use in this project. That loss was disappointing but the other trials we have will allow us to successfully complete the project. What opportunities for training and professional development has the project provided?This project has given opportunities so far for 1 graduate student (Julie Cardon) whose thesis is on organic apple rootstock performance. One post doctoral researcher (Luis Gonzalez) has also been a part of the organic rootstock trial planted in 2015. How have the results been disseminated to communities of interest?In 2022 the project leaders gave 3 presentations to apple grower groups to disseminate the results of this project. We have also published 2 articles in a natinal grower magazine about our work on rootstocks for organic apple growers. We have also released 3 new apple rootstocks that will be useful to organic apple growers in the next 10 years. What do you plan to do during the next reporting period to accomplish the goals?Next year we will study soil microflora as influenced by rootstock genotype in organic soils. We will also study root exudates from different rootstock genotypes. We will also study molecular markers of rootstock traits associated with high performance in organic management sustems.

Impacts
What was accomplished under these goals? Objective 1. An organic apple rootstock trial was conducted at Geneva NY.After 8 years tree size (TCA - cm2), could be separated into five different groups. The most dwarfing stocks in this trial are G.16 and G.222, followed by a slightly more vigorous group of G.969, G.214, G.11, G.935. A more vigorous group consisted of G.41 and M.9. A semi-dwarfing group comprises G.202, and G.30. In the semi-vigorous category was G.890 which was the most vigorous stock in the trial. Tree survival was lowest for G.16 followed by G.222. G.890 had the most root suckers followed by G.935, G.30 and G.16. All other stocks had less than 1 sucker per tree.The most productive rootstock in 2022 was G.214 followed by G.890, G.16, G.41, G.969, G.202, G.222, M.9 and G.11. However, when production is expressed in terms of yield efficiency, G.16 was the most efficient stock, followed by G.214 and G.222, G.969, G.41 and G.11. G.890, G.30 and G.202 were the rootstocks with the lowest yield efficiency in 2022.There were differences among stocks in fruit size in 2022. M.9 and G.41 had the largest fruit size followed by G.202, G.890, G.11 and G.969. G.935 and G.30 were the rootstocks with the smallest fruit size. Cumulative yield was greatest with G.890 followed by G.41, G.30 and G.935. The lowest cumulative yield was with G.222 and G.16. Cumulative yield efficiency was greatest with G.935 followed in order by G.214, G.41, G.11, G.16, G.969, G.222, G.30, M.9 and last was G.202 and G.890. Early conclusions indicate that G.935 and G.41 are promising rootstocks for organic production of Modi apple in a high-density system. For a medium density system, G.890 has shown good promise. A new rootstock trial was planted in a certified organic site at the Geneva experiment station in the spring of 2022.The trial compares 15 different rootstocks in a replicated design. In both 2022 we sampled the soil adhering to the roots of these trees for DNA extraction in order to characterize both bacterial and fungal microorganisms in the rhizosphere of the rootstocks in our research. We also established an aeroponic greenhouse trial to sample rhizodeposits from 6 of the rootstocks used in the orchard trial, with the aim of characterizing plant metabolites which are exuded from roots with untargeted HPLC/LCMS. Objective 2.We have measured the effect of rootstock on mineral concentration in the peel of 'Honeycrisp' in 2 plots in NY State (Geneva 2010 Honeycrisp plot and Geneva 2014 Honeycrisp plot). We correlated the K/Ca ratio in the fruit peel) and bitter pit of Honeycrisp apple (Robinson and Fazio, 2022). The results of these studies support our earlier results that showed rootstock genotype has a large influence on bitter pit incidence and on the fruit nutrient levels of the peel (Fazio et al., 2019). In these studies, we have confirmed that B.9 in most cases has low bitter pit incidence. We have also identified several new Geneva® rootstocks which have low bitter pit incidence (G.214, G.969, G.935 and G.65) and other rootstocks that have high bitter pit incidence (G.210 and M.7).?

Publications

  • Type: Journal Articles Status: Published Year Published: 2022 Citation: Fazio, G., Aldwinckle, H.S. and Robinson, T.L. 2022. Selection of apple rootstock breeding families for Phytophthora crown rot resistance. Acta Hortic. 1346, 717-722 DOI: 10.17660/ActaHortic.2022.1346.90 https://doi.org/10.17660/ActaHortic.2022.1346.90
  • Type: Journal Articles Status: Published Year Published: 2022 Citation: Robinson T. and G. Fazio. 2022. Rootstock affects fruit nutrient profile and bitter pit incidence of apple. Acta Hortic. 1333, 373-378.
  • Type: Journal Articles Status: Published Year Published: 2022 Citation: Robinson, T.L. and Fazio, G. 2022. Rootstock evaluation should not only measure yield efficiency but also potential yield and crop value at the optimum projected spacing. Acta Hortic. 1346, 775-782 DOI: 10.17660/ActaHortic.2022.1346.99 https://doi.org/10.17660/ActaHortic.2022.1346.99
  • Type: Journal Articles Status: Published Year Published: 2022 Citation: Fazio, G., J.C. Bettoni, L. Carvalho Costa, O.P. Hurtado-Gonzales, M. Al Rwahnih, A. Steinberger, A. Nedrow, G.M. Volk, S. Adams, R. Adams, T. Robinson. 2022. Virus Studies in the Geneva� Apple Rootstock Breeding Program. Fruit Quarterly 30:(2):4-6.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Miranda Sazo, M., L. Cheng and T.L. Robinson. 2022. Nutrient uptake and accumulation of Honeycrisp trees as affected by four rootstocks from establishment (2017) to maturity (2021). Abstracts of the ASHS Annual Meeting in Chicago IL. Aug. 1, 2022 (50 people
  • Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Robinson, T. and G. Fazio. 2022. The role of rootstock on fruit nutrient profile and bitter pit incidence of apple. Abstracts of the ASHS Annual Meeting in Chicago IL. July 31, 2022 (60 people)
  • Type: Journal Articles Status: Published Year Published: 2022 Citation: Fazio, G. and T.L. Robinson. 2022. Time analysis of rootstock mediated nutrient transport in Honeycrisp. Acta Hortic.1333, 405-412
  • Type: Journal Articles Status: Published Year Published: 2022 Citation: Fazio, G. and Robinson, T.L. 2022. Apple rootstocks can modulate the chilling requirements of grafted scions. Acta Hortic. 1346, 723-728 DOI: 10.17660/ActaHortic.2022.1346.91 https://doi.org/10.17660/ActaHortic.2022.1346.91