NC_OLD140: ROOTSTOCK AND INTERSTEM EFFECTS ON POME- AND STONE-FRUIT TREES
(Multistate Research Project)
Status: Inactive/Terminating
NC_OLD140: ROOTSTOCK AND INTERSTEM EFFECTS ON POME- AND STONE-FRUIT TREES
Duration: 10/01/2002 to 09/30/2007
Administrative Advisor(s):
NIFA Reps:
Non-Technical Summary
Statement of Issues and Justification
The NC-140 Regional Research Project is designed to address a number of high-priority areas within the North Central Region as well as other parts of North America. This project seeks to enhance economically and environmentally sustainable practices in temperate fruit production by focusing on rootstocks. The NC-140 project meets all guidelines presented by the North Central Regional Association (NCRA) in Guidelines for Multistate Research Activities (May 2001). Specifically, it addresses high priorities defined by NCRA, within the crosscutting research areas of agricultural production, processing, and distribution, genetic resource development and manipulation, and integrated pest management. The project is multidisciplinary and multistate and directly benefits society. Further, Federal and state dollars leverage significant additional resources. Lastly, outreach is integral to the project and includes electronic information transfer through web sites, much written material for growers and other stakeholder groups, and numerous educational programs in individual states and at national and international grower and scientific meetings.
With the increasingly competitive international market, the growing demand for higher quality fruit by consumers, the strong pressure to reduce chemical use, and an ever increasing need to enhance the economic efficiency of production, tree-fruit growers must look to alternative economically and environmentally sustainable management strategies for production. Growers who want to stay profitable must establish high-density plantings with much smaller trees with new scion cultivars. These high-density plantings may cost several times more to establish than low-density plantings, thus greatly enhancing the economic risk. Rapid returns are also vital for providing the ability to change cultivars in response to market or genetic opportunities. The central component of high-density systems is the rootstock. The root system imparts many characteristics to the mature tree such as size, precocity, productivity, fruit quality, pest resistance, stress tolerance, and thus profitability.
As the industry moves from low- to high-density plantings, several rootstock-related problems must be addressed. New pome- and stone-fruit rootstocks cannot be recommended to commercial growers without reservations until there is sustained research as to soil and climatic adaptability, root anchorage, size control, precocity, productivity, pest resistance, and propagation ability. In general, field testing of rootstocks in an orchard setting requires a minimum of ten years to assess accurately the potential for improved profitability, reduction of inputs, and enhancement of production efficiency. With year-to-year variation in weather, this time span is necessary to obtain a true indication of rootstock performance.
The establishment of the NC-140 technical committee in the 1970s enabled researchers to develop a coordinated effort in apple rootstock research through the uniform testing of rootstocks and multiple genetic systems, and to discuss, evaluate, and coordinate other rootstock research. Since NC-140 is the only regional project focusing on apple rootstock problems, researchers from around North America (see Appendix E) have joined the committee. Stone-fruit crops and pears were included in the project in its 1982 revision.
A stable tree-fruit industry based on economically and environmentally sustainable orchard systems is one of the primary goals of NC-140 research. Prior to the organization of NC-140, knowledge of rootstock and multiple genetic system performance and adaptability had to be obtained from a number of unrelated studies. The lack of common planting materials, spacing, and cultural procedures made comparison of the results of these studies difficult, and slowed the accumulation of knowledge that could be applied by orchardists. These difficulties resulted in serious planning and management errors. Also, such unrelated studies have been incomplete or slow in evaluating rootstock tolerances to biological, environmental, and edaphic stresses. Through the uniform cooperative testing undertaken by NC-140, new rootstocks can be exposed quickly and systematically to widely varying soil and climatic conditions to shorten the time necessary for thorough evaluation.
Evaluation and Environmental Effects
Each rootstock may react differently with a particular scion cultivar under a particular training system or in a different environment. This interaction makes it necessary to field test rootstocks that may be profitable for North American growers across a wide range of environments with appropriate orchard-training systems. Orchard systems must be designed to meet the specific needs of each fruit crop. In past years, the free-standing, central-leader system has been very profitable for North America, particularly with the weak, spur-type Delicious cultivar. As labor became more expensive and the list of profitable cultivars started changing rapidly, some North American growers began converting to smaller, high-density orchard systems. Also, tree response under a particular management system in different areas in North America can vary greatly. These problems require that rootstocks be tested under several North American climates and that modifications of training and pruning techniques be developed to match local growing conditions.
Ultimately, any newly developed rootstock must exist as an integral part of a total orchard-management system. Current economic trends make production efficiency of new scion/rootstock combinations under various cultural-management systems one of the most important factors that must be evaluated thoroughly before specific combinations are recommended for large-scale plantings by fruit growers.
The experimental design most commonly used to evaluate rootstocks at a single location is the randomized complete block design (RCBD). In a RCBD, the plot of land that is available for the experiment is usually divided into a number of blocks (often rows), based on orchard location. The assumption is that soil and environmental conditions are more uniform within blocks than between blocks. One tree on each rootstock is assigned randomly within each block. In early NC-140 rootstock trials, fewer than 10 rootstocks were compared, and RCBD was probably appropriate. Recently, the NC-140 rootstock trials have included 20 rootstocks. The RCBD may not be appropriate for these large blocks, because variation within blocks increases as block size increases. An alternative experimental design may be preferable. Our objective is to determine which experimental design is most efficient using data generated from the project.
Rootstock Propagation
Knowledge of the propagation characteristics of newer rootstocks and reasons for incompatibility between cultivars and rootstocks is a continuing need. Some promising pome- and stone-fruit rootstocks presently cannot be considered for commercial use because of difficulty in rooting clonal material using existing techniques. Alternative methods of propagation only recently have begun to offer solutions to these problems. Using different propagation methods such as hardwood or softwood cuttings, which are not commonly used, may be very effective for mass production of some of the rootstocks that do not propagate well by conventional means. Expanded research with micropropagated plant material needs to be done to document genotypic and phenotypic stability, thereby anticipating potential problems before widespread adoption by the fruit industry occurs. These techniques may also allow early screening of plant material for desirable characteristics such as disease and insect resistance.
Genetic Resources
If the pome- and-stone fruit industry is going to continue to change to meet the needs of the consuming public, new genetic material will need to be incorporated into existing material to enhance performance of rootstocks. Rapid means to screen potential rootstock candidates or breeding materials for susceptibility to various biotic stresses is vital. Using both traditional plant breeding and genetic engineering methods, researchers can incorporate insect and disease resistance into existing rootstock material, as well as develop rootstocks with enhanced horticultural performance as a greater understanding of the physiology of multiple genetic systems is elucidated. Obtaining genetic material from research programs from throughout the world and testing these new rootstocks cooperatively has been an integral part of the project. Clonal materials of different rootstocks have been obtained from many countries since the inception of the NC-140 project and will continue. The 1994 apple rootstock trial contains rootstocks from England, Poland, Russia, and the United States. As a result of this and the previous NC-140 apple plantings, one of the Russian rootstocks is being propagated and sold extensively to orchardists in North America. Additionally, the first commercially important dwarfing cherry rootstock originated in Germany and was identified as having commercial value by the 1987 NC-140 Rootstock Trail.
Physiology and Stress
In multiple genetic systems, rootstock can dramatically alter the developmental physiology of the scion. That is, rootstock can alter meristem determination (flower bud formation) and carbon partitioning (tree vigor, fruit quality, and shoot growth). Similarly, rootstock can alter abiotic stress tolerance of the scion, such as cold hardiness, drought tolerance, or adaptability to differences in soil chemistry or physics. One or more of these factors limit the use of existing rootstocks, and potentially will limit the adaptability of some new rootstocks within North America. Understanding how different rootstocks affect developmental and abiotic-stress physiology can lead to recommendation for use or non-use under certain orchard conditions. Such studies must include factors contributing to developmental differences or stress tolerances, development of practical means for controlling various stresses, or development of rapid means for screening potential rootstock candidates for susceptibility to various stresses. A better understanding of the physiological mechanisms behind these responses may allow for development of cultural practices that relieve the detrimental effects of stress.
Cooperative testing of new and existing rootstocks by NC-140 researchers continues to generate interest and support from the fruit and nursery industries. This interest has resulted in industry financial support for the establishment and management of cooperative plantings, grants for state rootstock research, and propagation of trees for several of the NC-140 plantings. It is estimated that over the term of the current project (2002-2007), nearly $2,000,000 will be received to support its research from sources other than universities and Hatch Multi-State Research Funds, and more than one half of this total will come from grower organizations.
A compelling need exists to continue the present coordinated studies and to initiate new studies for both pome- and stone-fruit rootstocks, as new plant materials are made available. Continued testing will provide a thorough evaluation of promising rootstocks, multiple genetic systems, and planting and training system efficiencies. This research project has led and will continue to lead to sound recommendations to growers and nurseries based on widespread knowledge of adaptability and performance of the plant material.
Related, Current and Previous Work
Evaluation and Environmental Effects
Promising new tree-fruit rootstocks are continually being introduced from worldwide sources (Beckman, et al., 1997; Bessho and Soejima, 1992; Cummins and Aldwinckle, 1994; DeJong et al., 2001; Fischer, 2001; Johnson, et al., 2001a; 2001b; Perry et al. 2000; Reighard et al., 2001a; Webster, 2001). Many of these new introductions will be propagated by North American nurseries for sale to U.S. and Canadian producers and to international markets. Without a coordinated, unbiased scientific approach to their evaluation, pome- and stone-fruit growers, who together plant about 30 million fruit trees a year, will be left with very little and often conflicting information on which to base a rootstock and planting system choice (Barritt et al., 1997b; DeJong et al., 1997). The wrong choice can be economically devastating (Barritt, 2000) for the grower and jeopardize the long-term supply of pome and stone fruits for North American and international customers.
Past studies document the effects of rootstock on survival, tree size, and cropping (NC-140, 1996b; 1996c; Perry et al., 2001a), horticultural characteristics (NC-140, 1996a), bud development (Conrod et al., 1996; Hirst and Ferree, 1995), fruit ripening and quality (Autio et al., 1996), and winter injury (Warmund et al., 1996). The 1997- 2002 review cites these studies and concludes that no single rootstock is widely adapted to the range of conditions in North America. Superior productivity, precocity, and vigor control are still very important for new orchard designs. New rootstock cultivars, with added pest resistance, increased hardiness, and better root anchorage are urgently needed. Since rootstocks are the foundation of the orchard (Barritt, 2000) they remain a key to the design of a profitable high-density orchard system (Perry and Byler, 2001). Orchard designs are now more complex, as new cultivars like the low-vigor Honeycrisp and new tree-training systems with their inevitable interactions are added to the high-density design puzzle. It is necessary to answer these questions through rigorous, long-term testing prior to making rootstock recommendations. Only then will increases in competitiveness and profitability (Barden and Marini, 2001) be assured. NC-140 rootstock studies currently in progress will identify genotype response across a wide array of soils and climates in the fruit growing regions of the United States and Canada (Autio et al., 2001a, 2001b; Marini et al., 2000a; 2000b). Documenting differences across climatic and edaphic conditions, whether it is longevity for peach (Perry et al., 2000) or vigor control and general performance for apple (Autio et al., 2001b; Barritt et al., 1997a; Marini et al., 2000a; 2000b), pear (Azarenko, et al., 2000), and cherry (Perry et al., 1997) is the common goal for new NC -140 collaborative studies.
In many trials, rootstock and location interact to affect tree performance (Autio et al., 2001a). Finding the exceptions and interactions with cultivars and the rootstocks (Autio et al., 2001b; Domoto et al., 2001) on which they are grafted is of considerable value for the local producing region. The NC-140 committee is gaining confidence in predicting performance of certain genetic combinations, yet there is hesitancy to reduce the scope of the trials to just the sites with extremes in environment. The science of biometrics which strives to extract useful information from old data may be able to play a useful role in this perplexing question. This is especially important for the low vigor sites. Interactions highlight problems with our generally accepted view that harsh growing conditions would yield greater losses. Frequently, some of the top performers in one site perform poorly in another.
Marini et al. (2000b) points out that there are low-vigor sites at which none of the semi-dwarf rootstocks differed in size. If these NC-140 trials make it is possible to classify tree growth for the North American production regions into high, low, and medium vigor it could be a major accomplishment. Regional planting recommendations will become much more data-dependent rather than subjective as is sometimes the case today. Much more work on tree mortality and management effects need to be analyzed and interpreted. A shift to rootstocks that fit an environment-first approach to orcharding is gaining attention and may require new efforts or at the least the redirection of some (Reighard et al., 1997; Webster, 2001).
An unforeseen benefit of these cooperative studies is the building of an important data base. This resource could be highly valuable for numerous other research purposes, such as providing quantitative data on the impact of climate change. Repeatable findings which show the rootstock and interstem effects on field performance for pome- and stone-fruit trees grown across the major fruit producing regions of North America require long-term, well managed, and carefully documented field experiments (Autio, 1999; Johnson et al., 2001a; Perry et al., 2000). Using these data to determine the extent and patterns of climatic effects on orchard-system performance is a research goal of NC-140 with apples (Johnson et al., 2001b), pears (Azarenko et al., 2000), cherries (Perry et al., 1997), and peaches (Reighard et al., 2001a).
Rootstock Propagation
Currently only a few scientists have initial studies underway so no scientific reports are available. Tree fruit propagators utilize traditional stool bed and hardwood cutting techniques. Tissue culture is gaining momentum and especially where only small quantities of certain genotypes are available and need to be increased rapidly (Jacyna et al., 2000).Considerable efficiencies could be achieved if new genotypes could be screened at the shoot or root multiplication stages in the tissue culture laboratory.
Genetic Resources
New tree fruit rootstocks have been and are being introduced from worldwide sources (Beckman et al., 1997; Bessho and Soejima, 1992; Cummins and Aldwinckle, 1994; DeJong et al., 2001; Perry et al., 1997; Reighard, 2000; Reighard et al., 2001a; Webster, 2001). It is also from local (Johnson et al., 2001a) and international work that new rootstocks are identified. A coordinator who may or may not be the breeder takes the lead in assembling this material. Since the plant material must be quarantined before it is released it often takes a number of years from first contacts until the trial is ready to plant (Kappel et al., 1998). Since there are many weaknesses in many of the currently recommended rootstocks this search is considered an important part of the project activity list.
It is also recognized that new technology like gene transfer (Aldwinckle et al., 2000) will play an important role in the development of the next generation of plants. The potential in this field is enormous; however, field performance is still a prerequisite to recommendation for industry adaptation. This committee is again strategically positioned to advance this technology.
Resistance to specific pests will be sought as well. As new tree-fruit rootstock trials are planned by NC-140 these concerns will be given careful consideration. It is also recognized that basic studies are needed to advance this area of knowledge. New hybrid Prunus rootstocks which confer precocity, and/or vigor control to sweet cherry are being tested for sensitivity to virus inoculations and cold stress (Lang et al., 1997). New rootstocks for peach that are more resistant to biotic and abiotic stresses such as soil diseases, fine soil texture and cold temperatures still need to be found (Perry et al., 2000).
Physiology and Stress
Current and previous research has attempted to determine the spectrum of environmental adaptability for currently available rootstock genotypes. Their sensitivity to cold stress as measured by blackheart in the trunk is becoming well documented (Domoto et al., 2001; Embree et al., 2000; Warmund et al., 1996). Controlled environment studies have also attempted to screen a large array of new rootstock genotypes for hardiness (Privi and Embree, 1997) and to simulate weather events (Privi et al., 2001). Finding new high-performing rootstocks less susceptible to the rigors of the North American production areas for apples, pears, cherries, and peaches is a clear need (Autio et al., 2001b; Barritt, 2000; Conrod et al., 1996). New emphasis is currently espoused to address the anticipated change in climate. Some predict that rootstocks will have to be more competitive for nutrients and water as inputs decline because of loss of agricultural chemicals and environmental concerns (Webster, 2001).
It is also accepted that a more critical understanding of the fundamental physiology of rootstocks performance is a first step in advancing the holistic nature of this research project (Fernandez et al., 1997; Ferree and Schmid, 2001; Johnson and Lakso, 1991). The fundamental reasons for the large differences in vigor between regions have, for example, not yet been discovered and documented (Domoto et al., 2001; Tartachnyk and Blanke, 2001). It is also recognized that these are complex, genetically compound plants which are difficult to study (Lang et al., 1997; Psarras et al., 2000; Reighard et al., 2001b). Real advancements in our current knowledge of whole-tree physiology helps the committee focus on the critical unknown elements of performance thereby increasing research efficiency for the overall goals of the project as well (Psarras and Merwin, 2000).
Objectives
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To evaluate the field performance of pome- and stone-fruit rootstocks in various environments and under different management systems, and to optimize experimental design for such evaluations.
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To assess and improve asexual propagation techniques of pome- and stone-fruit rootstocks.
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To develop and improve pome- and stone-fruit rootstocks through breeding and genetic engineering, and to acquire new rootstocks from worldwide sources.
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To understand the developmental and abiotic stress physiology of rootstock/scion interactions in pome- and stone-fruit trees.
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Methods
Objective 1: To evaluate the field performance of pome- and stone-fruit rootstocks in various environments and under different management systems, and to optimize experimental design for such evaluations.To evaluate performance of rootstock material in different climatic and edaphic environments, current replicated and randomized uniform trials will be maintained, and new trials will be established across North America as part of the NC-140 project. Promising new and existing rootstocks and multiple genetic systems possessing desirable characteristics have been or will be selected. They will be evaluated with respect to precocity, productivity, size control, anchorage, suckering, pest resistance, adaptability, and production efficiency. To provide a more thorough knowledge of tree performance, studies will be conducted to evaluate the performance of various orchard systems, including different cultivars on new and existing rootstocks and multiple genetic systems under various high-density orchard management systems. These systems will be evaluated for precocity, productivity, ease of management, fruit quality, and production efficiency. These trials will be maintained and data will be collected according to specific uniform guidelines established by the technical committee. For each trial, data to be collected will include a preplant soil test, weather, root suckering, tree growth as measured by changes in trunk cross-sectional area, tree height, canopy spread, precocity, yield, and fruit size. Trials will be concluded after 10 growing seasons. Data will be transmitted annually to trial coordinators in Virginia (1994 dwarf apple), Virginia (1994 semidwarf apple), South Carolina (1994 peach), British Columbia (1998 Western sweet cherry), Michigan (1998 Eastern sweet cherry), Michigan (1998 tart cherry), New York (1998 apple), Massachusetts (1999 dwarf apple), Massachusetts (1999 semidwarf apple), South Carolina (2001 peach), California (2002 peach), Oregon (2002 pear), Massachusetts (2002 apple), Virginia (2003 apple), Oregon (2004 pear), Michigan (2004 tart cherry), British Columbia (2005 sweet cherry), and Virginia (2006 apple). Standard statistical analyses will be performed on all data, and trials will be summarized for joint publications after five and 10 years of testing. Plantings being maintained for evaluation or proposed are as follows:
(a) 1994 Dwarf Apple. In 1994, an apple rootstock trial with Gala as the scion cultivar and dwarf rootstocks was planted in a total of 25 locations (AR, CO, GA, IL, IN, IA, ME, MA, MI, NJ, NC, two in NY, OH, two in PA, SC, TN, UT, VA, WA, WI, BC, NB, and ONT). Rootstocks included were M.9 EMLA, M.26 EMLA, M.27 EMLA, M.9 RN29, M.9 Pajam 1, M.9 Pajam 2, B.9, B.491, O.3, V.1, P.2, P.16, Mark, P.22, B.469, M.9 Fleuren 56, V.3, and M.9 NAKBT337.
(b) 1994 Semidwarf Apple. In 1994, an apple rootstock trial with Gala as the scion cultivar and semidwarf rootstocks was planted in a total of 23 locations (AR, GA, IL, IN, IA, KY, ME, MI, NC, NJ, NY, OH, PA, SC, TN, UT, VT, VA, WA, WI, BC, NB, and ONT). Rootstocks included P.1, V.2, G.30, and M.26 EMLA.
(c) 1994 Peach. In 1994, a peach rootstock trial with Redhaven as the scion cultivar was established in 20 locations (AR, CO, GA, IL, IN, KS, KY, MD, MA, MI, two in MO, two in NJ, NY, OH, SC, TN, UT, and ONT). Rootstocks included were Lovell, Bailey, Tennessee Natural 281-1, Nemaguard, Starks Redleaf, GF.305, Higama, Montclar, Rubira, Ishtara, Myran, S.2729, Chui Lum Tao, Tzim Pee Tao, H7338013, H7338019, BY520-8, Guardian, and Ta Tao 5/Lovell rootstocks were included. At three sites (MO, OH, and SC), the effects of these rootstocks on low-temperature tolerance of flower buds will be assessed.
(d) 1998 Western Sweet Cherry. In 1998, a sweet cherry rootstock trial was established in CA, two in OR, UT, WA, and BC with Bing on Mazzard seedling, Mahaleb seedling, Gisela 4, Gisela 5, Gisela 6, Gisela 7, Giessen 195/20, Giessen 209/1, Giessen 318/17, Weiroot 10, Weiroot 13, Weiroot 53, Weiroot 72, Weiroot 154, Weiroot 158, and Tabel Edabriz.
(e) 1998 Eastern Sweet Cherry. In 1998, a sweet cherry rootstock trial was established in MI, NY, PA, SC, and ONT with Hedelfingen on Mazzard seedling, Gisela 5, Gisela 6, Gisela 7, Giessen 195/20, Weiroot 10, Weiroot 53, Weiroot 72, Weiroot 158, and Tabel Edabriz.
(f) 1998 Tart Cherry. In 1998, a tart cherry rootstock trial was established in MI, NY, PA, UT, WI, and ONT with Montmorency on Mahaleb seedling, Gisela 5, Gisela 6, Gisela 7, Giessen 195/20, Weiroot 10, Weiroot 13, Weiroot 53, Weiroot 72, Weiroot 158, and Tabel Edabriz.
(g) 1998 Apple. In 1998, an apple rootstock trial was established in 13 locations (MA, MI, MO, NC, NJ, OH, three in NY, UT, WA, BC, and NS). Cultivars included Gala and Jonagold, and rootstocks were G.16N, G.16T, M.9, and M.9 EMLA.
(h) 1999 Dwarf Apple. In 1999, an apple rootstock trial was established in 20 locations with McIntosh (MA, MI, MN, two in NY, PA, VT, ONT, and NS) and Fuji (CA, IN, KY, MO, OH, NC, two in PA, SC, UT, and WA) as scion cultivars. Rootstocks included were CG.4013, CG.5179, CG.5202, CG.3041, CG.5935, G.16N, G.16T, M.26 EMLA, M.9 NAKBT337, Supporter 1, Supporter 2, and Supporter 3.
(i) 1999 Semidwarf Apple. In 1999, an apple rootstock trial was established in 20 locations with McIntosh (MA, MI, MN, two in NY, PA, VT, ONT, and NS) and Fuji (CA, IN, KY, MO, OH, NC, two in PA, SC, UT, and WA) as scion cultivars. Rootstocks included were CG.6210, G.30N, G.30T, CG.7707, CG.4814, M.26 EMLA, M.7 EMLA, and Supporter 4.
(j) 2001 Peach. In 2001, a peach rootstock trial was established in 14 locations, including Redhaven (IN, MI, MO, NJ, UT, and ONT), Cresthaven (CO, IL, TX, and WA), and Redtop (CA, GA, MD, and SC) as scion cultivars. Rootstocks used were BH-4, SLAP, SC-17, Lovell, Bailey, Cadaman, Julior, P30-135, Jaspi, Pumiselect, Hiawatha, K145-43, K146-44, and VVA-1.
(k) 2002 Peach. In 2002, a peach rootstock trial will be established in 16 locations with Redhaven (CA, KY, MA, MD, MO, OH, PA, SC, and ONT) and Cresthaven (CO, IL, MO, NJ, NY, TX, UT, WA, and MEX) as scion cultivar. Rootstocks to be included are Adesoto 101, MRS 2/5, Penta, VSV-1, VVA-1, Pumiselect, Cadaman, and Lovell.
(l) 2002 Apple. In 2002, an apple rootstock trial will be established in 9 locations (IL, IN, MA, MI, NJ, NY, PA, BC, and MEX) with Gala as the scion cultivar. Rootstocks to be included are B.9Treco, B.9Europe, M.9Burgmer 756, M.9 RN29, and B.9 NAKBT337.
(m) 2002 Pear. In 2002, a pear rootstock trial will be established in CA, OR, WA (2 locations), WV, and BC. The trial will include Bartlett and Bosc on eight rootstocks.
(n) 2003 Apple. In 2003, an apple rootstock trial will be established in approximately 20 locations (yet to be defined) including Golden Delicious as the scion cultivar. Rootstocks may include G.11, CG.3007, CG.3029, CG.6210, CG.4210, JM1, JM2, JM4, JM7, JM 10, JTE-B, JTE-C, JTE-D, JTE-E, JTE-F, JTE-G, JTE-H, Bud.62-396, P.14, P.60, P.559, B.112, AR295-6, AR486-1, AR628-2, AR69-7, AR360-19, AR1-20, AR1-25, M.9 NAKBT337, M.20, Pi-Au 51-4, Pi-Au 51-11, Pi-Au 36-2, and Pi-Au 56-83.
(o) 2004 Pear. In 2004, a pear rootstock trial will be established in CA (3 locations), NY (2 locations), OR, WA (2 locations), WV, and BC. The trial will include Bartlett and Bosc on 16 rootstocks.
(p) 2004 Tart Cherry. In 2004, a tart cherry rootstock trial will be established. Locations, cultivars, and rootstocks are yet to be determined.
(q) 2005 Sweet Cherry. In 2005, a sweet cherry rootstock trial will be established. Locations, cultivars, and rootstocks are yet to be determined.
(r) 2006 Apple. In 2006, an apple rootstock trial will be established. Locations, cultivars, and rootstocks are yet to be determined. Other multi-state/province rootstock trials will be conducted on a regional basis, but will not involve the entire committee in the coordination. However, these will be reported as being under the work of NC-140. Tree performance in the projects will be evaluated as in previously mentioned rootstock trials. These projects include the following:
(a) In 1994 a pear cultivar/interstem trial was established at three locations (two in OR and one in WA). Scions included dAnjou, Bartlett, Bosc, and Comice. All trees had Bartlett seedling as the rootstock, and interstems included dAnjou, Bartlett, Bosc, Conference, or no interstem.
(b) In 1995, an apple trial was established at three locations (ME, MA, and NS) with Cortland, McIntosh, Macoun, and Pioneer Mac on B.491, B.146, P.2, P.22, V.1, V.3, B.469, P.16, B.9, M.9, M.9 NAKBT337, and Mark rootstocks in all combinations.
(c) In 1995, an apple trial was established at three locations (MA, PA, and NB) with Ginger Gold on B.491, P.2, P.22, V.1, V.3, B.469, P.16, B.9, M.9 NAKBT337, and Mark.
(d) In 1996, an apple trial was established at 16 locations across NS, NB, QUE, and ONT with Hartenhof McIntosh and Idared on YP, AR 86-1-25, B.490, and KSC7.
(e) In 1997, an apple hardiness trial was established at three locations in Canada (AB, MB, and ONT) with Goodland apple on Beautiful Arcade, Columbia, V.1, V.2, V.3, V.4, V.7, and M.9.
(f) In 1999, 2000, and 2001, apple trials were established in NY, MI, and WA of 5-10 promising new CG rootstocks from the USDA/Cornell rootstock breeding program to obtain an intermediate-stage evaluation of the rootstocks prior to NC-140 testing. NC-140 participants will continue individual research to evaluate various aspects of performance and physiology as they relate to rootstock and training system:
(1) evaluating the performance of various apple rootstocks and interstem combinations (AR, IA, MA, MN, NJ, NY, OH, and PA);
(2) evaluating performance of various pear rootstocks and interstem combinations (NY and OR);
(3) evaluating the performance of various peach rootstocks (SC);
(4) evaluating the performance of various cherry rootstocks (MI, NY, and WA);
(5) studying the interaction of scion cultivar and rootstock (MA, MN, and NY);
(6) determining rootstock effects on fruit quality, maturity, and size distribution (MA and PA);
(7) studying the performance of management and training systems with various species and rootstocks (NY and PA); and
(8) studying rootstock performance under organic production systems (MI). Data sets from NC-140 rootstock trials (AR, CA, CO, GA, IA, IL, IN, KY, MA, MD, ME, MI, MO, MN, NC, NJ, NY, OH, OR, PA, SC, SD, TN, UT, VA, VT, WA, WI, BC, NB, NS, ONT, and MEX) will be used to identify sources and magnitudes of variation in three response variables (trunk cross-sectional area, yield efficiency, and cumulative yield per tree) occurring within and among sites and blocks, and among rootstocks. These data sets will be used to evaluate three different aspects of experimental design and this information can be used to more efficiently design future rootstock experiments (NY and VA).
(a) Determining the number of replicates. Data from the 1994 NC-140 dwarf apple rootstock planting, with 14 rootstocks at 26 locations, will be used to determine the appropriateness of blocking and to determine how many replicates should be used in future experiments when one tree per rootstock is assigned to each block. This data set will be analyzed two ways. First it will be analyzed as a replicated-randomized-complete-block design (RCBD), where blocks are nested in locations. The effect of using different numbers of sites and different numbers of blocks within sites, will be determined using the least-significant-difference procedure. Second, to learn more about the variation between rootstocks and blocks at each site, analyses of variance will be performed for each site. The effect of using different numbers of blocks at each site will also be determined using the least-significant-difference method.
(b) Blocking efficiency. The experimental error mean squares of the ANOVA from the RCBD will be compared to the estimated experimental error for a completely random design (CRD) that could have been conducted. Relative efficiency (RE) will be estimated and used to compare the number of replications in a CRD compared to the number of blocks in a RCBD.
(c) Evaluating subsampling. In 1990, a NC-140 trial was established as a RCBD at 8 sites. At each site there were four blocks, and plots of six trees per rootstock were randomized within each block. There were a total of 24 trees per rootstock, but only four blocks at each site. Data were collected from the interior four trees, and plot means were analyzed by ANOVA. During the last two years of this 10-year trial, several cooperators submitted data for individual trees. An ANOVA will be performed to identify and separate the sources of within- and between-site variation in trunk cross-sectional area, yield per tree, and yield efficiency. Variances will be calculated and the least significant difference technique will be used to determine numbers of trees per block, and blocks per site needed to detect differences of a desired magnitude at the 5% level of significance.
Objective 2: To assess and improve asexual propagation techniques of pome- and stone-fruit rootstocks.
Laboratory, greenhouse, and field studies will evaluate the propagation characteristics of existing and new rootstocks and develop improved means of asexual propagation for different materials. Studies contributing to this project include:
(1) developing improved tissue-culture techniques to propagate apple, pear, and cherry rootstocks (NY and NS);
(2) managing tissue-culture-propagated material after removal from culture (NY and NS);
(3) improving softwood and hardwood cutting techniques (NJ and OR); and enhancing germination of peach seed (NJ); and
(4) improving the stoolbed-propagation performance of hard-to-manage apple rootstocks such as G.30 (NY).
Objective 3. To develop improved pome- and stone-fruit rootstocks through breeding and genetic engineering, and to acquire new rootstocks from worldwide sources.
To enhance tree performance and pest resistance, traditional breeding programs will pursue improved rootstocks for apples (AR and NY), pears (OR), cherry (MI), and peaches (SC). Tolerance of rootstocks and multiple genetic systems in relation to pathogenic organisms will be investigated through evaluation of performance of trees in the trials listed under Objective 1. Additional work will be conducted, including:
(1) apple rootstock tolerance of or resistance to fireblight (NY and ONT), crown rot (NY), latent viruses (NY), lesion nematode (NY), and specific apple replant disease (NY);
(2) peach rootstock tolerance or resistance to nematodes (SC and ONT), peach tree short life syndrome (SC), and Armillaria root rot (SC); and cherry rootstock tolerance or resistance to ilarviruses (WA), Armillaria (MI), and bacterial canker (OR). Further, genetic engineering procedures will be used to enhance pest resistance of apple rootstocks (NY). Work will continue to map Prunus genome (MI and SC) and isolate markers for nematode resistance and use them in breeding programs (SC). Significant effort also will be made to acquire new or unique material from around the world for future tests (MI, NY, OH, BC, and NS).
Objective 4. To understand the developmental and abiotic stress physiology of rootstock/scion interactions in pome- and stone-fruit trees.
Studies will be conducted to elucidate developmental physiology and stress tolerance of fruit trees as influenced by new and existing rootstocks. Basic rootstock performance data will be collected as part of the evaluation of rootstocks in the trials listed under objective 1; however, additional, more-detailed additional studies will be conducted by individual cooperators using these same rootstocks. Physiological studies of rootstock-induced changes in scion physiology will be conducted to better understand and select valuable traits in new multiple genetic systems. Such studies include altered carbon partitioning (CA, MI, NY, and WA), meristem determination (MI), and gene expression (MI). Stress-physiology studies will include:
(1) the cold hardiness of rootstocks and the influence of rootstock on scion cold hardiness for apple (IA, MN, NY, SD, UT, VT, NB, ONT, and NS), peach (MO), and cherry (UT);
(2) the relationship between blackheart injury in apple and yield decline (MO);
(3) the relative sensitivity of apple rootstocks to soil compaction (OH);
(4) the periodicity of root growth of apple rootstocks (NY);
(5) graft-union strength of apple rootstocks (NY); (6) nutritional stress related to orchard-floor management on apple (MI); and (7) the relative sensitivity of apple rootstocks to drought (MEX).
Measurement of Progress and Results
Outputs
- The primary output of this project has been and will continue to be unbiased information on the field performance, biotic and abiotic stress tolerance, and propagation of fruit tree rootstocks in different climates and soils across North America.
- The best measurement of progress in this project will be the continued flow of information to our stakeholders through both oral presentations and publications (refereed, grower, and internet) from each of the uniform multi-state orchard plantings and from rootstock work done by the individual cooperators.
- Since the last project revision, this project has published refereed reports on six multi-state rootstock trials (the 1984 peach planting, the 1988 pear planting, the 1990 apple cultivar/rootstock planting, the 1990 apple rootstock trial, the 1990 orchard systems/rootstock trial, and the 1994 apple rootstock planting).
- Publications from individual researcher under the objectives of this project will also be an important measure of success, and since the last rewrite of this project, there have been more than 150 publications by individual researchers.
Outcomes or Projected Impacts
- The impact of this project will be measured by the changes the fruit industry makes in adopting new improved rootstocks and by the prevention of serious rootstock failures and associated economic losses.
- The information developed through this project is vital to the economic success of the North American fruit industry.
- Fruit growers need to replant old orchards to remain competitive in the world fruit market, but the high level of investment required and the long-term nature of the investment to plant new orchards require that growers make sound research-based decisions of which rootstock and cultivar to plant.
- If the wrong rootstock is used, it can result in low production and reduced profitability or in the worst case, death of the trees and significant economic losses.
- The results of this project prevent mistakes by the industry and identify rootstocks that are more productive and thus more profitable than existing rootstocks.
- This project has already become the primary source of information on rootstocks for the North American tree-fruit industry in each fruit production regions of the continent. <LI>As results from this project are made available, the fruit industry has made and will continue to make changes in the rootstocks used.
Milestones
(0):border=1 cellpadding=2 cellspacing=1> <tr> <td>Year</td> <td>Interim Reports Planned</td> <td>Final Reports Planned</td> <td>New Plantings Planned</td></tr> <tr><td>2002</td> <td>1998 Apple<Br> 1998 Western Sweet Cherry<br> 1998 Eastern Sweet Cherry<br> 1998 Tart Cherry<br> </td> <td>1988 Pear <br> 1990 Plum<br> 1992 Apple <br> 1993 Apple<br></td> <td>2002 Apple<br> 2002 Peach<br> 2002 Pear</td> </tr> <tr> <td>2003</td> <td>1988 Pear <br> 1990 Plum<br> 1992 Apple <br> 1993 Apple</td> <td>1994 Peach</td> <td>2003 Apple</td> </tr> <tr> <td>2004</td> <td>1999 Dwarf Apple<br> 1999 Semidwarf Apple</td> <td>1994 Dwarf Apple<br> 1994 Semidwarf Apple </td> <td>2004 Tart Cherry<br> 2004 Pear </td> </tr> <tr> <td>2005</td> <td>.</td> <td>. </td> <td>2005 Sweet Cherry </td> </tr> <tr> <tr> <td>2006</td> <td>2001 Peach</td> <td>.</td> <td>2006 Apple </td> </tr> <tr> <td>2007</td> <td>2002 Apple<br> 2002 Peach<br> 2002 Pear<br> </td> <td>1998 Apple Rootstock<br> 1998 Western Sweet Cherry<br> 1998 Eastern Sweet Cherry<Br> 1998 Tart Cherry </td> <td>.</td> </tr> <tr> </table>(0):0
Projected Participation
View Appendix E: ParticipationOutreach Plan
Our results will be communicated by: 1) sharing annual reports among participating states at annual meeting 2) refereed research publications 3) non-refereed grower publications in national fruit-grower magazines and via our website 4) extension publications in each state prepared by members in the project 5) oral presentations at national fruit-grower meetings and 6) regular meetings with fruit tree nurserymen in North America. Electronic outreach will occur primarily through our web site (http://www.NC140.org). Results will include reprints from refereed-journal, popular-trade-magazine, and extension-newsletter articles and PowerPoint. presentations of poster and professional talks.
Plantings will be summarized for publication in professional journals. Most refereed journal publications will be in the Journal of the American Pomological Society. Some planting results will be summarized for grower audiences and published in popular trade publications. International publication will occur primarily through the International Dwarf Fruit Tree Associations periodical, Compact Fruit Tree (available in printed form and at http://www.IDFTA.org). State/province cooperators will also publish grower articles of results and recommendations in appropriate extension newsletters, fact sheets, and experiment station reports and bulletins. Additional outreach will occur through numerous educational programs at on-farm field days, twilight meetings, and winter education meetings within each state/province and annually at the Annual Meeting of the International Dwarf Fruit Tree Association.
On a state/province basis, stakeholder advisory groups will be convened annually as part of their extension mandates. Special effort will be made when assembling these advisory groups to be inclusive of under-served and under-represented farmers and non-farmer stakeholders, such as consultants, support-service providers, environmental advocates, and consumers.
Organization/Governance
This regional Technical Committee will be organized for the North Central Region as outlined in the Guidelines for Multistate Research Activities. The executive committee shall consist of the chairperson, vice chairperson, secretary, immediate past chairperson, the coordinator of each NC-140 trial, and the crop committee chairs. Each year a secretary will be elected to serve for one year, and the past vice-chairperson and the secretary will advance to the next higher office commencing in January. Members of the executive committee will set the annual meeting agenda, write and distribute the minutes and annual report, and act on the Committees behalf if necessary. An Administrative Advisor will act as an advisor to the Committee on procedures and policies related to regional research and provide coordination and communication with other regional projects and the North Central Directors. Annual meetings will be held for the purpose of evaluating current work, planning future work, and coordinating publications of a regional nature which may result from the work undertaken in the regional project. Each year, the chairperson will be responsible for organizing the leading the annual meeting, the vice chairperson will submit the annual report, and the secretary will submit minutes.
For projects established under Objective 1, coordinators will be appointed on a continuing basis to coordinate the trials: Marini (VA)-1994 dwarf apple; Marini (VA)-1994 semidwarf apple; Reighard (SC)-1994 peach; Kappel (BC)-1998 Western sweet cherry; Lang (MI)-1998 Eastern sweet cherry; Lang (MI)-tart cherry; Robinson (NY)-1998 apple; Autio (MA)-1999 dwarf apple; Autio (MA)-1999 semidwarf apple; Reighard (SC)-2001 peach; Johnson (CA)-2002 peach; Autio (MA)-2002 apple; Mielke (OR)-2002 pear; Marini (VA)-2003 apple; Mielke (OR)-2004 pear; Lang (MI)-2004 tart cherry; Kappel (BC)-2005 sweet cherry; and Marini (VA)-2006 apple. These coordinators will provide technical oversight concerning those plantings, maintain contact with the participants through correspondence, transmit pertinent information to participants and the Committee to insure uniformity of the studies, prepare data collection forms and details of coordinated procedures which will permit a consolidation of the research findings, assemble and analyze combined data or summarize data previously analyzed, initiate all publications regarding the planting, and report annually to the Committee on progress of the planting.
Standing committees for each major crop will be appointed to plan, assemble plant material, and propagate trees for future multi-location uniform trials: Robinson (NY)-apple; Meilke (OR)-pear; Reighard (SC)-peach; Kapple (BC) and Lang (MI)-cherry; and Andersen (NY)-plum.
The Hatch Multi-State Research Funds expended on NC-140 (among all the cooperating states) will leverage approximately $2,000,000 of additional funds from various granting organizations, including Federal and state agencies, local grower organizations, and the International Dwarf Fruit Tree Association. The Executive Committee will oversee funding requests in support of the NC-140 project, including the pursuit of IFAFS grants.
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