Current Production Research
The following are a brief synopsis of the projects being funded by growers through the Oregon Hazelnut Commission during the 2006-07 year. If you are interested in copies of the full reports, please contact the industry office by phone 503-678-6823 or email at hazelnut@oregonhazelnuts.org
Hazelnut Breeding Program Synopsis 10-25-06
By Shawn MehlenbacherThe hazelnut breeding program at Oregon State University uses the genetic diversity in the genus Corylus to create new cultivars for the Oregon industry. The major objectives are suitability to the blanched kernel market and resistance to eastern filbert blight (EFB). Three recent releases ('Lewis', 'Clark', and 'Sacajawea') have quantitative resistance, while 'Santiam' has complete resistance from 'Gasaway'. Dozens of promising selections are in yield trials, and a few are being evaluated in grower orchards. We have also identified suitable pollinizers for these new releases.
OSU and USDA have assembled the best hazelnut collection in the world. Recent additions include seedlings from nuts collected in Turkey, Azerbaijan, Georgia, Armenia, Russia, and the Crimea. From this collection we continue to identify sources of EFB resistance. In addition to 'Gasaway' and 'Zimmerman', complete resistance has been identified in Minnesota seedling OSU 408.040, Spanish cultivar 'Ratoli', Russian selection OSU 495.072, Georgian selection 759.010, Serbian cultivars 'Uebov' and 'Crvenje 3/96', and most recently 'Yagli Findiq' from Azerbaijan. Turkish selections have been excellent parents for yield and kernel quality.
Research projects complement the on-going breeding program. DNA markers are routinely used to identify seedlings likely to carry the EFB resistance allele from 'Gasaway', and markers linked to three other sources of resistance have been identified. Microsatellite markers have been developed and used to fingerprint cultivars and investigate genetic diversity in the collection. We have developed more than 150 microsatellite markers to date. Microsatellite markers will allow us to assign all simply inherited traits, including the many sources of EFB resistance, to a linkage group.
Advanced Selections: Evaluation, Phenology and Rootstocks
By Becky McCluskeyAdvanced selection evaluation
Efforts to develop cultivars that combine EFB-resistance with improved yield and kernel quality have been an ongoing collaborative effort between Dr.s Azarenko and Mehlenbacher since the mid-1980's. Currently, there are ~100 selections in six trials that are being evaluated for their potential as new cultivars, including 40 that were planted in spring 2006. Resistant hazelnut selections must first pass through 3-6 years of evaluation by Shawn Mehlenbacher, and the best of the survivors are propagated and placed into trials for further testing by Becky McCluskey. Trees are evaluated an additional 7-8 years for yield, nut and kernel size, kernel quality, growth habit, and tree size.
All selections going into advanced trials since 1998 have carried genes conveying complete resistance to EFB. In February 2005, 'Santiam', tested as OSU 509.064, was released as the first cultivar to be completely resistant to EFB. Trees of 'Santiam' are slightly smaller than 'Barcelona', and produce small nuts that have fewer defects and a higher percent kernel. Nuts mature and fall free of the husk two to three weeks before 'Barcelona', a real advantage in avoiding fall rains. There are several advanced selections currently being considered for new cultivar releases. These selections combine improved kernel quality and complete disease resistance with favorable growth habit and in some cases, larger nut size.
Pollen quality and time of shed
As new cultivars become available, questions arise regarding compatible pollinizers, pollen quality and quantity, and male and female bloom periods. Many of the new selections have delayed female blom or pollen shed relative to the existing commercial cultivars.
Beginning in winter of 2003-2004, data collection on pollen shed and female bloom time has been added to the evaluation protocol. Bloom and pollen shed information is recorded for 2-3 years on any given selection. Compatible selections producing late pollen have been identified and will be evaluated for bloom, growth habit and nut quality over the next several years.
Rootstock evaluation
The use of grafted trees is an option to producing a large number of trees in a short period of time, or of converting trees from one cultivar to another. Rootstocks may also be useful in extending the range of suitable production areas for a particular cultivar. Rootstocks, however, need to be selected with care as they may have a positive or negative influence on precocity, vigor, yield and nut quality of the grafted tree. Two rootstock trials are currently being observed and include 'Clark' grafted onto three of the VR selections in 2001, and 'Lewis' self-rooted and grafted onto the four EFB pollinizers 'Gamma', 'Delta', 'Epsilon', and 'Zeta', in 2004. As the industry transitions to EFB resistant varieties it will be helpful to have suitable rootstocks available to facilitate the process.
Availability of findings
Members of the Oregon hazelnut industry are the first to receive information on new cultivars, promising selections and pollinizers. This information is made available through extension publications, orchard tours, or at grower meetings. An annual report is presented to the hazelnut commission at the end of each fiscal year.
Extension publications describing cultivars released by OSU are available to download at:
Micropropagation of Hazelnut
By William ProebstingWe have developed an effective method for micropropagating hazelnut varieties in tissue culture. This is a method that commercial micropropagation labs are able to use. Micropropagation is a much more rapid technique of propagation than layering, cutting or grafting. Therefore, as Shawn Mehlenbacher develops EFB-resistant varieties, they can made available to growers much more quickly than by conventional methods.
Using tissue culture, Shawn can anticipate which EFB-resistant clones are promising candidates for release and establish them in tissue culture years prior to release. When the final decision is made, established cultures can be immediately sent to commercial labs. This saves an additional one to two years, because nurseries are unwilling to tissue culture clones which may not be commercialized.
Synopsis of EFB Management Program
By Jay W. PscheidtOur overall objective has been to develop the tools needed to control Eastern Filbert Blight (EFB), understand the limitations of these tools and integrate them into an effective disease management program for hazelnut growers of the Pacific Northwest.
Annual testing of various chemical and biological fungicides has helped find cheaper and more effective products, avoided unnecessary applications of ineffective products and has generated data directly responsible for the successful application and generation of emergency use, special local needs and full use labels. This list of materials includes Abound, Bravo, Cabrio/Pristine, Echo, Elite, Flint, Orbit, Procure, and Rubigan.
At the request of growers, pruning recommendations were modified based on research into the severity of pruning cuts to rid trees of EFB cankers. A new education program will incorporate 35 years of survey data into disease progress maps and will help educate growers about disease spread.
Several ideas have been researched but proved ineffective for EFB control and thus have avoided unproductive disease management activities. Injection of infected trees with fungicides was one of these ineffective ideas. The development of a forecasting system, GrammaCast, helped time fungicide applications. Although the system saved fungicide applications over a multi year period, it resulted in increased disease levels over standard recommendations. Biological control of EFB may be possible but not without many more years of development.
Details of EFB from life cycle, disease spread, to fungicide effectiveness can be found on line at The Eastern Filbert Blight Help Page.
Development of Integrated Filbert worm Pest Management Strategies
By Vaughn Walton, OSU EntomologistProduction of hazelnuts is severely crippled by various insect and mite pests, and one of the more severe key pests includes filbert worm. Also, little information is available as to the filbert worm species composition attacking filberts in the Willamette Valley area as there are reports of a smaller species attacking filberts recently. The composition of these species may also impact on the effective trapping and monitoring of filbert worm. Recent and current information regarding the above aspects concerning this pest may greatly influence decision making for effective control protocols.
The objectives of the project are to determine whether timing of filbert worm trapping is appropriate, to sample fruit from these orchards in order to determine the species composition of filbert worms attacking hazelnuts, and to determine what natural enemies currently attack filbert worm in the Willamette Valley.
Foliar Fertilizers on Hazelnuts: Summary of Results to Date
Project Leader: Jeff Olsen, OSU Extension HorticulturistCooperator: Joe Cacka, Western Farm Service
The objective is to determine if the use of foliar fertilizer programs increase hazelnut yields in a cost effective manner. This study provides a side by side comparison of six different commercially available foliar fertilizer programs in a mature Barcelona orchard, and will compare yields and economic costs and benefits of those six programs. The treatments were applied at monthly intervals for three consecutive months being in May, except for the Foliar Advance treatment which was applied once in the first year and twice in the second year. The six treatments were:
| Treatment | Rate/acre |
| 1) Untreated Control | None |
| 2) Foliar Advance + Break Thru | 1.5 gals. + 1.5 oz. |
| 3) Multi Mineral Metalosate | 0.5 gals. |
| 4) Stimplex + Break Thru | 0.5 gals. + 3 oz. |
| 5) Nutrient Express 4-41-27 or 18-18-18 | 10 # + 1 qt. + 1# + Calexin + ZMC Express |
| 6) Foliar Gold + Integrity Ca + Z422 + Phortress + K-Nite+ BreakThru | 2.1 gals + 2.8 pts. + 0.7 pts. + 0.7 pts. + 2.8 lbs. + 2.1 oz. |
| 7) Kelpgrow | 1 qt./100 gals. |
There were no statistically significant differences in any of the treatments compared to the untreated check in the first year of the research. There were also no significant differences in the weights or grades from any of the treatments or the untreated check. The second year of the treatments was identical to the first on the same orchard, with the harvest just now being completed at the time of this report. The statistical analysis of the second year's data will soon follow.
