Location: National Clonal Germplasm Repository2011 Annual Report
1a. Objectives (from AD-416)
Strategically expand and improve genetic resource collections and associated information for priority fruit, nut, and other specialty temperate climate crops (and their wild relatives), especially, hazelnut, strawberries, hop, mint, pear, currants, gooseberries, brambles, blueberries, cranberries, hardy kiwifruit, and other small fruits. Strategically characterize, genotype and phenotype, priority fruit, nut, and other specialty crop genetic resources adapted to temperate climates for key traits such as genetic variability, adaptation, product quality, and other horticultural traits. Efficiently and effectively conserve and regenerate priority fruit, nut, and other specialty crop genetic resources adapted to temperate climates, and distribute disease-free samples and associated information worldwide.
1b. Approach (from AD-416)
Plant exploration expeditions will be taken in North Africa, Central Asia, Northern Europe for pome fruit and in China, Japan, Russia, Korea, Central and South America for berry crops. Plants from these areas will fill current gaps. Collecting trips will occur in collaboration with foreign scientist and quarantine officials. Horticultural and botanical experts in taxonomy will be consulted to verify the identity of accessions. Primary collections of woody plants will be maintained in field collections. Primary collections of herbacious perennial genera will be maintained in a screenhouse and repropagated. Duplicate plants will be maintained on site. Available plant materials will be distributed for research purposes. Backup hazelnut collection will be maintained in Parlier, California. Backup of small fruit, mint, and hop will occur on site. Tropical or sub tropical accessions will be protected from temperature extremes. Core collections will be propagated in vitro and in cryogenic storage at NCGRP, Fort Collins. Primary collections will be tested for pathogens and infected accessions will be subjected to therapy procedures to develop pathogen free replacments. Microsatellite fingerprinting sets will evaluate genetic diversity and determine clonal identity of blueberries, strawberries, hazelnuts, and pears. Clonal collections will be evaluated for high priority phenotypic characters including phenology, plant habit, fruit characters, and incidence of naturally occurring disease. Molecular and phenotypic information will be loaded to the public GRIN database. Formerly 5358-21000-033-00D (3/08).
3. Progress Report
This report serves to document the research conducted under project 5358-21000-038-00D Management of Temperate Adapted Fruit, Nut, and Specialty Crop Genetic Resources and Associated Information. New plant material was acquired from Japan and the United States. More than 10,000 plant accessions were maintained at the Corvallis Repository. Plant material was backed up in Ft. Collins, CO, and Parlier, CA. Improved protocols for tissue culture and cryogenics of temperate fruit crops were developed. Just under 7,000 accessions were distributed to national and international researchers. Phenotype and genotypic plant information was loaded to the Germplasm Resources Information Network (GRIN), a public database of the US collections. Hop plants were tested for hop stunt viroid. Phytoplasma testing was continued on strawberry and hop. The hazelnut collection was monitored for, and protected from infection by eastern filbert blight. The Repository was certified free of sudden oak death. Identities of hazelnut, blueberries, hops, pears, strawberries, and raspberries were determined by molecular marker technology by simple sequence repeated DNA. Platforms for single nucleotide polymorphisms were set up. DNA sequencing for some of the species were initially examined.
1. Fingerprinting of fruit and nut crops. Industry sometimes has difficulty in determining the identity of different types of berries, fruit trees and nut trees. Researchers at ARS in Corvallis, Oregon, developed and archived molecular fingerprints for cultivated blueberries, cranberries, red and black raspberries strawberries, pears, quince, and hazelnuts. These baseline identification patterns are worth more than $15 million considering the amount of matching funds provided by the small fruit, pome fruit, nut, and hop crop communities,including industry and private sources.
2. Improved pear tissue culture. The availability of pear rootstocks is key to improved profitability of plantings for pear growers and improved methods for pear tissue culture is needed to keep up with the demand for new propagation requested by pear growers. Tissue culture is useful because it can provide many plants in a short amount of time. Researchers at ARS Corvallis, Oregon, developed improved tissue culture media. They are optimizing the nutrient combinations and concentrations for pear tissue culture so that rootstock trees can be reproduced faster. High density plantings which depend on large numbers of tissue culture plants, come into production sooner, showing a profit in year 6 compared to year 9 for standard planting, and reach 56 tons per hectare at full production compared to 45 tons for the standard planting, an increase in profit of $10,378 per hectare. Establishment costs are recovered in year 10 for high density systems versus 21 years for the standard spaced planting.
3. Identity and disease evaluation of Quince. Quince is used for a dwarfing rootstock for pear and sometimes it can be injured by low winter temperatures. Researchers at ARS in Corvallis, Oregon, evaluated diverse quince cultivars for 4 types of fungal disease resistance, cold hardiness, and identity (using molecular markers). They identified 13 types of quince that were very cold hardy, resistant to fireblight and other diseases. Quince is grown on about 300 acres in California, and is a prized specialty fruit. Current pear rootstock selections do not impart sufficient dwarfing to the scion to accommodate yield efficient, high-density planting designs, but quince could be useful for these applications. These newly identified cold-hardy, disease resistant quince selections may lead to a better rootstock for pear. Even a modest 10% increase in pear production is worth tens of millions of dollars to the industry.
4. Evaluation of ohelo for fruit production and as an ornamental potted plant. Native stands of ohelo, a blueberry relative, are being decimated on the Hawaiian islands. Also production of alternative crops are being sought for Hawaiian farmers. Researchers in ARS in Corvallis, Oregon, collaborated with those in Hawaii to evaluate ohelo plants for commercial tissue culture potential, molecular fingerprinting, and fruit nutrient composition. They determined that ohelo seed dormancy could be broken by cryogenics; developed successful commercial tissue culture working with private collaborators; determined cryogenic preservation protocols and transferred the technology to base genebank collections; determined unique fingerprints for ohelo cultivars that were recently released; determined that the low growing ohelo berry has similar fruit nutrient composition to that of cranberries. Cultivation of this fruit could protect wild endangered populations and could replace part of lost farming that was estimated at $150 million in 2006 when the sugar producers left.
5. Molecular identity of black raspberry cultivars. For the past century, many berry researchers have wondered about the identities of black raspberries. Researchers at ARS in Corvallis, Oregon, used molecular markers to examine the identity of black raspberry cultivars in the National Rubus collection. Surprisingly, 6 black raspberry cultivars with different names were identical. Furthermore, 'Munger,' the most commonly grown cultivar, had 12 variants. This newly discovered genetic variation of ‘Munger’ could have resulted in variation in field performance and thus affected grower and processing industry profitability. Further study is needed to evaluate the extent of this potential loss of genetic diversity and the economic effect of genetic variability in the most commonly grown black raspberry cultivars.
6. Discovered new wild strawberry form. Incorporating wild germplasm is essential to broadening the gene pool of plant material that breeders can choose from. Researchers from ARS Corvallis, Oregon, found that some of the wild strawberries in the high peak region of the Oregon Cascade Mountains have 10 sets of chromosomes (decaploid) instead of the usual 8 sets. Strawberry samples from across the US were also analyzed and the Oregon samples are the only native decaploid strawberries observed thus far. Samples from the Cascades in Washington State and California had 8 sets of chromosomes. A new botanical name will be published for this strawberry form. This form could be crossed with other wild decaploid species to become a separate group of cultivars with a higher number of chromosomes. The value of this wild form is unknown at this time but adds to the rich diversity of American berry plants.
Nathewet, P., Hummer, K.E., Iwatsubo, Y., Sone, K., Yanagi, T. 2010. Karyotype Analysis in Octoploid and Decaploid Wild Strawberries, Fragaria (Rosaceae). Cytologia. 75(3):277-288.