15 June 1998

Considering that there is a great deal happening in the USDA/Cornell apple rootstock breeding and evaluation project, I have decided use this web site as a tool to help me keep in touch with the cooperating nurseries, growers, and interested researchers. As you may now know, this is a USDA-ARS sponsored project, and the research that we do here is a public service for the domestic industry. I seek your input and suggestions for how to improve the project and the lines of communication between Geneva and the nursery and apple industries.

In the letter below I will describe personnel changes on the program, the new methods we are developing for disseminating information on rootstock cultivars, our efforts to clean up prior mis-identification problems and prevent future misidentifications, plans for applied research programs, plans for a possible future visit to the West Coast, and an overview of very promising trial results from our European collaborators with the Geneva rootstock genotypes. This is likely the only newsletter-type mailing that you will receive, because in the future all of the updates on the Geneva rootstock program will be provided on our new website, which you will read about below.

Flyer

At the request of Frank Greene, USDA associate area director, I have developed a one page document describing the apple rootstock breeding and evaluation program to provide general background information to interested parties. I will append this document as a Word 6.0 attachment, and for those of you without access to Word 6.0 files I will also include the text at the end of this letter.

Personnel

Since I joined the rootstock breeding program this past February to fill the vacancy created by Jim Cummins' 1993 retirement, one of the primary difficulties with the project has been that there was little continuity in the program. Jim Cummins has been available for consultation, and has helped greatly in prioritizing the program. Charlie Bennett, the field assistant who has been working on the project for several years, has been of great assistance in getting us new folks oriented and trained in propagation methods.

Since joining the project in February I have had the good fortune to hire two additional well qualified people. In April, Todd Holleran joined the project in the position formerly held by Dave Gill as the Research Support Specialist. Prior to joining the rootstock breeding and evaluation program, Todd was working with the clonal germplasm repository at the USDA-ARS Plant Genetic Resources Unit. He brings excellent propagation skills, spreadsheet and database experience, management experience, a degree in biological sciences, and an appreciation for precise handling and labeling.

In late May Kim Gollinger joined the group as a temporary assistant to help with data entry and data management. We now have the human resources to put the breeding program in excellent order. Todd, Charlie, Kim, and I will continue to work closely with Herb Aldwinckle and Jay Norelli on evaluation of materials from their transgenic apple rootstock program.

Website

As part of our efforts to make the rootstock breeding and evaluation project more transparent, we will be developing a website that will provide comparative information on rootstock genotypes (not limited to material from the Geneva program); information on current directions in the rootstock breeding program (planned crosses; intended purpose of crosses; populations currently in evaluation stages) and information on the status of plant material and trial data for all released genotypes from the Geneva program. There will likely be an additional limited-access portion of the webpage that will be available only to Cornell-Geneva nursery license holders to help coordinate the exchange of trial information and plant material of elite genotypes between the cooperating nurseries. The website will be accessible via http://www.nysaes.cornell.edu/hort/faculty/johnson/. The information on status of elite CG rootstock genotypes will be placed on a website by August, and the other information will be posted as it becomes available. We intend for this site to be a source of information for all interested parties, and plan to build on the site over time so that it becomes a valuable resource for information.

One area in which we will request assistance from domestic nurseries will be in providing lists of less common rootstock genotypes available for purchase (non-Geneva materials), so that we will be able to provide growers with up to date sources for plant material. I encourage nurseries (not only CG licensees) to pay attention to this site as it develops, as I will include hyperlinks to commercial websites that are sources for rootstock genotypes. As the site develops, please feel free to give suggestions and constructive criticisms.

Identity verification

One of the challenges for the breeding program has been that questions remain about the correct identification of several genotypes that have been distributed from the program. In February, Terence Robinson and I collected plant material from several of the nurseries in Washington and Oregon so that I will be able to use molecular markers to verify their identity. Since that time I have identified several additional genotypes with questionable records, and this portion of the project has grown considerably.

At this time I am planning to begin the DNA extraction and marker analysis in July, and expect to have some preliminary results beginning in August. I will correspond directly with the nurseries and researchers from whom plant material was collected. At some point this year we will need to perform the marker verification work on all the plant material of several elite genotypes from all the stoolbeds in Geneva, as well as the stoolbeds of standard rootstock cultivars (M and MM series). In general, I expect that domestic nurseries are unlikely to find many additional mis-identifications, but our European cooperators may find some additional minor problems.

Nursery trials

After consultation with members of the Cornell nursery licensee group, we have decided to begin a program that will allow cooperating nurseries to establish stoolbed trials of elite genotypes beginning in the fall/winter '98/'99. Initially we are planning to distribute a limited number of genotypes (probably about 5 in the first year) to TRECO in Oregon and Willow Drive in Washington. This will allow the commercial nurseries to observe stoolbed performance directly and provide everyone with a better assesment of the commercialization potential for elite genotypes. TRECO and Willow Drive have agreed that they will allow other licensee nurseries to observe the stoolbeds and will share nursery performance data and plant material with the other cooperating nurseries as it becomes available.

Data management

Due to problems associated with turnover of people on the project, we have some difficulty establishing the continuity of genotypes through the various stages of the breeding program. We have available at Geneva a remarkable quantity of data, and our short-term goal is to get all the useful information, currently present only as hardcopy, entered into spreadsheet format to allow manipulation and evaluation.

Beginning in midsummer, we plan to begin converting much of the data into a database format to allow streamlined tracking of genotypes through the various phases of the breeding program. One of the changes will be in the designation of identification numbers to facilitate record keeping. We will be assigning all genotypes a six digit number that will remain with the genotype until commercialization, thus avoiding the confusion caused by duplication of the CG numbers with different pedigrees and helping to avoid misidentifications. We are hoping that this database will be functional by the end of this year so that we can gather all available information on a genotype easily.

Consolidation

Another project we are undertaking to streamline the operations of the breeding program is consolidation of fields. Presently the rootstock breeding project is by far the largest of the breeding projects at the Geneva station, and our fields include many older stoolbeds. Over the course of the next year, we will be determining which genotypes from the older stoolbeds may still show promise, and moving mother plants or re-establishing new stoolbeds at a single location. We will also be removing older orchards that are no longer critical to the program.

This consolidation will require considerable effort in the short term, but will improve the effectiveness of the program in the long term. At the same time we will be removing material that is no longer the focus of the program from the permanent stoolbeds, including breeding programs for disease resistant ornamental crabapples, pear rootstocks, and low-chill disease resistant fruit varieties. Our medium-term goal is to reduce the overall size of the breeding project by 30-50% so that we can focus more energy on evaluations of elite genotypes and commercially available cultivars.

NRSP5

Five additional genotypes, CG.935, CG.41, CG.202, and G.16, were sent to Prosser this spring for virus certification. These genotypes join CG.120, CG.103, CG.007, and CG.210 (76O3R5-210) which were submitted for certification in 1997. Certified budwood from this year's class of genotypes will be available for distribution to licensees beginning in the fall.

Second test orchards

Historically the project has performed intermediate stage evaluations (2 or 3 sites x 2 or 3 scions x 5 to 10 trees) of rootstock materials at locations in New York, West Virginia, and/or other Eastern locations. With the new USDA/Cornell cooperative agreement, the scope of the project has been broadened to include the entire domestic apple industry. In the future we hope to conduct these tests at environmentally diverse sites in the major apple production regions of the Pacific Northwest and Western New York. We are currently working on grant proposals to fund this research. We will continue to perform first stage evaluations (1 site x 1 scion x 3 or 4 trees) here in Geneva. We will also continue to utilize the NC-140 system for evaluations of promising genotypes identified in intermediate stage evaluations, and plan to enlist interested growers for semi-commercial trials of elite genotypes following intermediate stage evaluations.

Evaluation component

As we consolidate and streamline the rootstock breeding program, we will shift a major portion of our energy to evaluation of existing rootstock cultivars (not limited to Geneva materials). We plan to develop screening methods and orchard trials to evaluate existing rootstock genotypes for their reactions to the biotic and abiotic stresses important to commercial growers, and we will make this information available through our website and publications.

INRA trials

On a very encouraging note, I have obtained trial data for Geneva rootstock materials from our collaborators Drs. Marie-Helene Simard and Jean-Claude Michelesi of INRA, the French equivalent of the USDA, at Angers. They have well maintained stoolbed and orchard trials including 11 Geneva rootstock genotypes and the check cultivars M.27, MM.106, and Pajam-2 (M.9 clone). Although several of the genotypes will require molecular marker identity verification, a few of the Geneva rootstocks were standouts. CG.041, CG.013, CG.707, CG.202, and CG.179 showed high cumulative yield efficiency in the 4th and/or 5th leaf. Most notable, however, was G.11, which had the highest yield efficiency and largest fruit size in the trial, and had a tree size midway between M.27 and Pajam-2 in the 4th leaf.

West coast November trip

I am tentatively planning my next trip to Oregon and Washington the week of November 16 to attend the NC-140 coordinating meeting. I hope to spend several days in the region visiting with growers, researchers, and nursery operators as time permits. Please contact me if you are in OR/WA and would like to meet at that time.

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