1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter?
The research falls under National Program 301, Plant Microbial and Insect Genetic Resources, Genomics, and Genetic Improvement (100 percent), under Action Plan Component 2b Genetic Improvement.

Production of small fruit crops in the United States often is severely limited by various diseases. There is a need for research to develop varieties resistant to the major diseases. Our objective is to develop small fruit varieties (strawberry, black raspberry, thornless blackberry, blueberry, and cranberry) that combine resistance to common diseases of the eastern United States with the highest degree of fruit production, quality, and nutrition possible. We select disease resistant types for breeding new varieties, and develop improved disease screening methods to assure that our varieties are disease resistant under different growing conditions. We also study the interaction between the plants and the disease-causing organisms (fungi, bacteria, and other kinds of pathogens) to understand the mechanisms of infection and disease proliferation. This enables us to develop alternatives to chemical control.

Before the USDA began developing strawberry varieties with resistance to the red stele root rot disease, the production of strawberries in some parts of the country was not possible. Plant losses were nearly 100 percent. Resistant varieties have reopened these areas for strawberry production. Research needs to continue toward developing disease resistant varieties because of the threat of new races of the pathogen being introduced into production areas and the lack of chemical control for this disease. Similarly, Verticillium wilt and anthracnose of strawberry may severely limit fruit production. Anthracnose can be responsible for 80-100 percent fruit loss when weather conditions are favorable to the disease. The disease is particularly problematic in the annual raised ridge, plastic mulched production system. This system is rapidly replacing the traditional matted row production system in the southeast United States and portions of the Atlantic seaboard. The anthracnose disease cannot be adequately controlled with chemicals, but our recent progress shows that varieties can be developed that are resistant to the disease.

A 1994 survey of 44 states and six Canadian provinces where blueberries are grown listed mummy berry as the most common disease problem, and anthracnose fruit rot as the third most common problem. These concerns as well as the development of organic fruit production markets have highlighted the increasing need for resistant varieties. Economics of growing blueberry have also become a limiting factor as labor regulations have increased the difficulty of finding and keeping seasonal labor. There is an increasing need to have varieties suitable for machine harvest. The processing market, using berries for baked goods, freezing, juice, and jams, has also increased. Most berries harvested for processing have been either lowbush or third picking of highbush varieties, but now there is an increased interest in small-fruited highbush varieties strictly for processing.

Research allows scientists to select parents and breed disease-resistant strawberries and blueberries through traditional breeding methods and by molecular genetic manipulation, and to study disease causing pests that threaten small-fruit crops. Research provides growers with varieties with reduced pesticide use requirements and reduced cost to the grower. At the same time, varieties will be developed with high phytonutrient contents, such as vitamin C and other antioxidants that are important factors in the human diet. The program works with USDA and State cooperators in Arkansas, Florida, Georgia, Maryland, Michigan, Minnesota, Mississippi, New Jersey, New York, North Carolina, and Oregon.

2.List by year the currently approved milestones (indicators of research progress)
Year 1 (FY 2004) - Complete crossing for development of anthracnose resistant populations in blueberry. - Complete assay development for RRSV in blueberry. - Complete description of ‘funky flower’ in cranberry. - Complete germplasm evaluation for anthracnose resistance in strawberry. - Complete fruit quality evaluation of strawberry breeding selections. - Complete bramble frost avoidance studies.

Year 2 (FY 2005) - Complete screening of blueberry seedlings for resistance to mummy berry blight & fruit infection. - Complete evaluation of blueberry seedlings for firmness and horticultural characteristics under field conditions. - Complete AFLP development & begin cloning fragments differentially expressed in mummy infection in blueberry. - Complete strawberry frost avoidance studies. - Complete pallidosis detection method comparison in strawberry. - Complete evaluation of blackberry breeding selections and germplasm collection for sugar, acid, and antioxidant levels.

Year 3 (FY 2006) - Complete primary field evaluations for mummy berry in blueberry. - Complete blueberry germplasm evaluation for fruit quality and antioxidant activity. - Complete determination of blueberry volatiles associated with anthracnose fruit rot. - Select Colletotrichum-resistant strawberry progeny from germplasm enhancement crosses. - Complete Phytophthora fragariae race assignment in strawberry.

Year 4 (FY 2007) - Complete selection in blueberry anthracnose populations. - Complete marker development for mummy fruit infection in blueberry. - Complete strawberry Botrytis assay studies in strawberry.

Year 5 (FY 2008) - Complete primary field evaluations of disease resistant blueberry genotypes. - Complete evaluations of mechanical harvesting in blueberry selections. - Complete evaluation of wild strawberry germplasm collection for sugar, acid, & antioxidant levels. - Select F1 blackberry progeny.

4a.List the single most significant research accomplishment during FY 2006.
The causal agent of the new disease syndrome ‘Black Shadow’ was identified. Blueberry plants throughout the U.S. growing regions have begun to show signs of decline associated with the appearance of a black fungal infection on stems. This previously unknown pathogen was identified as a new species of Rhizosphaeria. This information will allow development of targeted control strategies. This research is carried out under National Program 301, Problem area 1 “Genomic Characterization and Genetic Improvement”.

4b.List other significant research accomplishment(s), if any.
Blueberry volatile analysis demonstrated wide variation in the levels and specific volatiles across ten cultivars. No association was found between the levels of antimicrobial volatiles and resistance to anthracnose fruit rot. This information suggests that these volatiles might be important for flavor and other characteristics, but will not be useful in selection for fruit rot resistance. This research is carried out under National Program 301, Problem area 1 “Genomic Characterization and Genetic Improvement”.

Parthenocarpy in highbush blueberry. Parthenocarpic fruit is seedless fruit that can develop without bee pollination. A study was completed evaluating the expression and inheritance of parthenocarpic fruit development. The trait appears to behave as a dosage dependent recessive trait. This trait has been incorporated into a number of selections in diverse genetic backgrounds. This research is carried out under National Program 301, Problem area 1 “Genomic Characterization and Genetic Improvement”.

Anti-carcinogenic compounds in blackberries. Cyanidin-3-glucoside was isolated from blackberry fruit and demonstrated to be an active compound that could retard tumor growth in mouse skin and reduce growth of human lung cancer cells. The study investigated the mechanisms of cancer inhibition by C-3G in mice and demonstrated that C-3G could inhibit tumor promoter-induced cancer growth in mice. This work paves the way for additional investigations on the mechanisms of how fruits and vegetables promote health benefits in human.

Temperature effects on strawberry lipids. The quality of strawberry fruit is greatly influenced by temperature during the growing season. This work identified the predominant membrane lipids and fatty acids in leaves, roots, and fruit of two cultivars of strawberry and found that strawberry fruit grown under cooler temperatures contained higher amounts of certain lipids than those grown under warmer temperatures. This information is helpful in understanding the role of membrane lipids in regulating strawberry plant growth in different temperature zones.

Effects of natural volatiles on anti-oxidants in post-harvest storage. Treatment of berry fruits with methyl jasmonate or essential oil of the tea tree immediately after harvest was effective in promoting the antioxidant capacity and antioxidant enzyme activities in berry fruits. These natural products also retarded decay of berry fruit during storage.

Effects of oxygen on anti-oxidants in post-harvest storage. Strawberry fruit treated with high concentrations of oxygen immediately after harvest maintained antioxidant values, and concentrations higher than 60% could promote increases in total phenolics, total anthocyanins, and oxygen radical absorbance capacity during the initial 7 days of storage. The effect diminished with prolonged storage. These results indicate that high oxygen treatments may improve the fruit quality and antioxidant capacity of strawberry fruit in storage.

4c.List significant activities that support special target populations.
none

4d.Progress report.
Organoleptic evaluation of blueberries was combined with laboratory analysis. The goal of this project is to determine how measurable fruit characteristics are perceived by consumers. This study is the first of this kind in blueberries and was initiated this year in collaboration with Beltsville Produce Quality and Safety lab. The information will allow for development of rapid lab-based assays to assist in selection of blueberry clones that would have potentially high public appeal.

Resistance of cranberry to fruit rot fungi. Fruit rot in cranberry can reach 100% in untreated plots. A wide array of fungal species across six genera cause the fruit rot. Selection of resistant clones will greatly reduce fungicide inputs. Several resistant clones were identified and are being evaluated for molecular markers that may be of use in selection for fruit rot resistance.

Resistance to fungal diseases in blueberry. Fungal diseases are serious problems for blueberry growers in most production areas, resulting in crop losses. ARS scientists at Chatsworth, New Jersey continue research on screening both parental material and offspring populations for resistance to mummy berry and anthracnose. Newer cultivars continue to be screened to identify sources of resistance; resistant offspring have been selected. Resistant offspring hold the promise of becoming future cultivars after necessary field-testing.

Antioxidant composition of small fruit. ARS scientists at Beltsville, Maryland have analyzed anthocyanin, flavonoids, and phenolic constituents as well as the antioxidant capacity in blueberry, cranberry, wild chokeberry and lingonberry. Cultivars with high antioxidant capacities were identified, and the contribution of individual anthocyanin, flavonoids, or phenolic acids to total antioxidant capacity determined. Information obtained from this research should be useful to breeders in selecting berry cultivars with high antioxidant content and to consumers concerned with the health benefits of small fruit.

5.Describe the major accomplishments to date and their predicted or actual impact.
The causal agent of the new disease syndrome ‘Black Shadow’ was identified. Blueberry plants throughout the U.S. growing regions have begun to show signs of decline associated with the appearance of a black fungal infection on stems. This previously unknown pathogen was identified as a new species of Rhizosphaeria. This information will allow development of targeted control strategies by industry..
1)This research addresses National Program 301, Component 2b: Genetic Improvement, 2)applicable ARS Strategic Plan performance measures, 3.2.4, 3.2.5.

Cyanidin-3-glucoside was isolated from blackberry fruit and demonstrated to be an active compound that could retard tumor growth in mouse skin and reduce growth of human lung cancer cells. The study investigated the mechanisms of cancer inhibition by C-3G in mice and demonstrated that C-3G could inhibit tumor promoter-induced cancer growth in mice. This work paves the way for additional investigations on the mechanisms of how fruits and vegetables promote health benefits in human..
1)This research addresses National Program 301, Component 2b: Genetic Improvement, 2)applicable ARS Strategic Plan performance measures, 4.1.2.

Two albino blueberry selections were released, as germplasm, in response to requests from the nursery industry. These selections address needs of the small-fruit industry and help the industry in the United States remain profitable..
1)This research addresses National Program 301, Component 2b: Genetic Improvement,.
2)applicable ARS Strategic Plan performance measures, 1.2.8.

Several blueberry cultivars were identified with good resistance to both foliar and fruit forms of anthracnose disease. Foliar resistance offers opportunities for breeding for lowered survival of over-wintering disease inoculum, and may help growers manage this disease under field conditions..
1)This research addresses National Program 301, Component 2b: Genetic Improvement,.
2)applicable ARS Strategic Plan performance measures, 3.2.4, 3.2.5.

The cold hardiness of various blueberry germplasm types was evaluated, and types with exceptional cold hardiness were identified. This information will assist in breeding for cultivars with better resistance to extreme winter temperatures and better resistance to damage from late spring frosts. This research addresses National Program 301, Component 2b: Genetic Improvement. .
1)This research addresses National Program 301, Component 2b: Genetic Improvement,.
2)applicable ARS Strategic Plan performance measures, 1.2.5.

Blueberry cultivars with high resistance to both stem blight and Phomopsis twig blight diseases were identified. These diseases are not readily controlled by normal fungicide applications. This information will allow the development of blueberry cultivars with better disease resistance..
1)This research addresses National Program 301, Component 2b: Genetic Improvement,.
2)applicable ARS Strategic Plan performance measures, 3.2.4, 3.2.5.

A new species of Phytophthora causing root rot in cranberry was identified. ARS scientists at Chatsworth, NJ in collaboration with P.V. Oudemans (Rutgers University), used molecular and morphological studies to identify the new species. This information will allow the improved diagnosis of disease problems in cranberry, and emphasizes the need for recognizing different species when evaluating disease treatments..
1)This research addresses National Program 301, Component 2b: Genetic Improvement,.
2)applicable ARS Strategic Plan performance measures, 3.2.4, 3.2.5.

6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products?
Two albino blueberry selections were released in response to requests from the nursery industry.

Blueberry seedlings have been transferred to breeding program cooperators at the USDA-ARS Small Fruit Research Center in Corvallis, Oregon, the University of Georgia, and the University of Arkansas. Advanced selections were transferred to USDA cooperators in Oregon, and State cooperators in New Jersey, Arkansas, Georgia, Michigan, and Minnesota. Cuttings of newer released cultivars were distributed to growers at Blueberry Field Days to encourage growers to evaluate new materials.

Technology for blueberry and cranberry phytoplasma detection was transferred to the MAF Biosecurity lab in Auckland, New Zealand.

Technology for DNA fingerprinting of blueberry for cultivar identification was transferred to Scientific Andes Biotechnologia Vegetal, Valdivia, Chile.

7.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below).
Ehlenfeldt, M.K. and K.S. Lewers. 2005. Blueberry and strawberry presentations at the NCR-22 Small Fruit Research Committee Meetings, October 24-28, 2005, Geneva, NY.

Lewers, K.S. 2005. ‘Strawberry breeding: What the future holds’. New England Vegetable and Fruit Conference. December 13-15, 2005. Manchester, NH.

Ehlenfeldt, M.K. 2006. ‘Concepts pertaining to yield in blueberry’. Vegetable Growers Association of New Jersey annual meetings, January 12, 2006, Atlantic City, NJ.

Polashock, J.J. 2006 ‘Segregating populations for mummy berry resistance’ Vegetable Growers Association of New Jersey annual meetings, January 10, 2006, Atlantic City, NJ.

VanPelt, D., J. Johnson-Cicalese, J. Polashock, N. Vorsa, and C. Ranger. 2006. ‘Altering cranberry fruit chemistry to improve antioxidant bioavailability’. American Cranberry Grower’s Association meeting. January 26, 2006, Mount Holly, NJ.

Lewers, K.S. 2006. Strawberry cultivars: What the future holds. Mid-Atlantic Fruit and Vegetable Convention. February 2, 2006. Hershey, PA.

Ehlenfeldt, M.K. 2006. ‘Concepts Pertaining to Yield in Blueberry, Part II. “Why are these Dukes so small ?”’. New Jersey Blueberry Growers Association annual meetings, February 23, 2006, Hammonton, NJ.

Lewers, K.S. 2006. ‘Imagine strawberries locally grown all year’. Technology Development Corporation (TEDCO). February 23, 2006. Beltsville, MD.

Polashock, J.J. 2006. ‘Stem blight and phomopsis resistance in blueberry-the final chapter’ Blueberry Growers Open House meeting. February 23, 2006, Hammonton, NJ.

Review Publications
Chanjirakul, K., Wang, C.Y., Wang, S.Y., Siriphanich, J. 2006. Effect of natural volatile compounds on antioxidant capacity and antioxidant enzymes in raspberries. Postharvest Biology and Technology. 40:106-115.