2012 Annual Report
Developed germination and propagation protocol for ohelo from seeds, cuttings and tissue culture to mature plants; identified best management practices including media, fertilizer, temperature, light, canopy training, insect and disease controls at three elevations in Hawaii, which contributes to objective 1 of the in-house project.
Information disseminated via University of Hawaii Extension publications. Seeds, plants and educational materials were distributed free of charge at 11 meetings to interested farmers and nurserymen. Developed seed based berry production protocols using container culture with proper medium, irrigation and fertilizers at three locations. In 2010, berry production at the Volcano nursery reached 50 lb. cumulative yield from fifty 3 year old plants in 2 gal. containers. Selected and released two varieties based on ornamental potential such as shape and color of new foliage and berry yield in two growing seasons. Streamlined in vitro propagation and conservation protocol at the Oregon repository and the technology was transferred to a commercial tissue culture laboratory/nursery in Oregon; nursery ready plugs of the two ohelo are available to the public since 2007 from the enterprise. Total cost estimated by allocating all costs by space and time varies considerably by nursery; the total cost at the Volcano research trial was $4.57 for each 3.5” container (12 month cycle) and $7.47 for each 6 inch container (18 m). Ohelo plants were sold at The Big Island Association of Nurserymen’s Annual Scholarship Plant Sale (via a Non-Funded Cooperative Agreement). We collected feedback from 100 customers and most believed there is a potential for ohelo as an ornamental potted plant. The USDA, ARS, PBARC Hilo and the University of Hawaii Cooperative Extension Service conducted eleven grower-cooperator events between 7/1/09 to 8/31/10, recruited 9 grower-cooperators. Two lowland ohelo selections may have resulted by the grower’s efforts. In June 2011, a nursery at Volcano purchased 3,000 tissue cultured ‘Kilauea’ and ‘Red Button’ plugs from Oregon for berry and plant production. These activities support objectives 1 & 2 to strategically expand and improve collection, evaluation and distribution of genetic resources and information.
Selected and released two cultivars, ‘Kilauea’ and ‘Red Button’ for berry production and as an ornamental potted plant through USDA/ARS, Technology Transfer Office(TTO). Co-operators at Corvallis repository established: (1) molecular fingerprinting of the released cultivars and compared to other Vaccinium species; the molecular fingerprinting is important in germplasm identification & verification. (2) Streamlined commercial tissue culture production of ohelo. (3) Developed long-term cryogenic storage of vegetative and seed samples. (4) Produced the first nutrient analysis of ohelo to explore future usage of ohelo beyond value added specialty products. The nutrient analysis of ohelo identified similarity of most anthocyanins to cranberry with exception of lower peonidin in Ohelo. Ohelo is a rich source of phenolics, and proanthocyanidins in the range of cranberry, and a close ohelo relative V. calycinum, (tree ohelo) in Hawaii had 10 times higher proanthcyanidins than cranberry. Proanthocyanidins with A-type linkages have been associated with preventing adhesion of P-fimbriated uropathogenic Escherichia coli to uroepithelial cells in humans. Identified environmental and management influence on ohelo qualities in production. The cooler temperature (<68°F) at higher elevations are preferred by ohelo growth and production, the temperature promotes red color development in young leaves. The color of young ohelo leaves are maroon when grown in warmer climates and are more susceptible to powdery mildew infection. Identified preference of four tephritid fruit flies to ohelo berries by USDA, ARS entomologist and developed rust and powdery mildew leaf disk and growth chamber trials for rapid screening of potential resistance among four genotypes and a seedling population. Accession N09-16 is less susceptible to powdery mildew than the other lines. ‘Kilauea’ has the best overall attributes and is more tolerant to powdery mildew than ‘Red Button’ and seedlings. Etiology of a causal agent of stem and root rot of ohelo berry was determined as Calonectria. All these activities relate to the parent project objective 3 to characterize and evaluate.