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United States Department of Agriculture

Agricultural Research Service

Research Project: MANAGEMENT OF GENETIC RESOURCES FOR VITIS, PRUNUS, JUGLANS, FICUS, OLEA, PISTACIA, PUNICA, DIOSPYROS, ACTINIDIA, AND MORUS

Location: National Clonal Germplasm Rep - Tree Fruit & Nut Crops & Grapes

2009 Annual Report


1a.Objectives (from AD-416)
The long-term objective of this project is conservation, characterization, and distribution of plant genetic resources of designated Mediterranean-adapted fruit and nut crops and their wild-species relatives. Over the next 5 years we will focus on the following objectives:

Objective 1: Strategically expand the genetic diversity in genebank collections and improve associated information for priority vine, tree fruit, and nut crops (and their wild relatives) adapted to Mediterranean-like climates. Sub-objectives: a. Acquire samples of Vitis, Prunus, Juglans, Pistacia, and Punica from Turkey and the Caucasus nations to fill current gaps in NPGS collections of these priority genera. b. Survey existing U. S. domestic (California and other states) collections of priority crops, identify material that would fill gaps in NPGS collections, and begin acquiring and characterizing them, initially emphasizing Vitis, Prunus, and Ficus cultivated material and germplasm of related wild species.

Objective 2: Conserve and regenerate priority vine, tree fruit, and nut crop genetic resources adapted to Mediterranean-like climates efficiently and effectively, and distribute disease-free samples (whenever feasible) and associated information worldwide. Sub-objectives: a. Conserve, regenerate, and distribute vine, tree fruit, and nut genetic resources and associated information, emphasizing Vitis, Prunus, Juglans, Ficus, Olea, and Punica. b. Backup primary collections of Vitis, Prunus, Juglans, Ficus, and Olea, via high-density nurseries, cryopreservation, and tissue culture. c. In collaboration with University of California, Davis Foundation Plant Services and the Canadian Plant Germplasm System, process 70 accessions of NPGS warm-season grapes through quarantine and make them available for distribution.

Objective 3: Strategically characterize (“genotype”) and evaluate (“phenotype”) priority vine, tree fruit, and nut crop genetic resources adapted to Mediterranean-like climates for molecular markers and key horticultural traits such as adaptation and product quality. Sub-objectives: a. In cooperation with other ARS and university collaborators, develop and apply new genetic markers for phylogenetic and genetic diversity analyses of priority crops, emphasizing simple sequence repeat (SSR) in Vitis, Prunus, Juglans, Ficus, Olea, and Pistacia. b. Generate SSR “fingerprints” for ca. 1,000 accessions of priority crops, emphasizing Vitis, Prunus, Juglans, Ficus, Olea, and Pistacia, and use them to determine the identity, diversity, and systematic relationships of these genetic resources, and to enhance the effectiveness of genetic resource management. Incorporate characterization data into GRIN and/or other databases. c. Extend ongoing cooperative research to evaluate horticultural quality for ca. 1,000 accessions of Vitis, Prunus, Juglans, Ficus, Olea, and Pistacia, and incorporate phenotypic data into GRIN and/or other databases.


1b.Approach (from AD-416)
Obtain new acquisitions to fill collection gaps and broaden diversity. Make contacts with appropriate institutions to exchange diverse germplasm. Through interactions with CGC's, develop exploration proposals. Engage in cooperative research on cryopreservation of buds. Place evaluation, passport, and source data on GRIN and local database. Expand assessment of genetic diversity by SSR technique and other molecular techniques in Vitis and other genera. Obtain descriptor data for traits of most value to users. Distribute to researchers worldwide. Inform public. Replacing 5306-21000-015-00D (3/08).


3.Progress Report
In FY 09 the repository acquired 148 new accessions representing 9 genera & 21 species though exploration & exchange in Azerbaijan. The entire collection of cultivated grape(~1300 accessions)has been genotyped for 8 polymorphic microsatellite loci identified by the Intl. grape consortium for global comparison of genotypic data. These data sets are useful for identification duplicates & clonal variation within accessions. Genotyping of Prunus collections using 16 microsatellite markers is nearly 80% complete. 194 Fig accessions have been genotyped for 17 microsatellte loci and data analyzed to demonstrate the genetic structure & differentiation within cultivated fig. A manuscript has been submitted to the Intl. journal “Genetica”. Olive collection has been analyzed to elucidate the genetic structure & differentiation. The study unraveled the genetic structure and differentiation within Olea europaea and contributed to the understanding of the domestication history of olives in Calif. and to management of the collection. In collaboration with the Davis USDA Crops Pathology group, a systematic screening of wild Juglans germplasm for crown gall(Agrobacterium tumefaciens), Crown & root rot(Phytophthora spp.), and Root-lesion & Root-knot nematodes has been conducted as part of a project funded by the Calif. Walnut Marketing Board to identify novel sources of resistance to soilborne diseases to develop resistant rootstocks. Walnut(Juglans regia)germplasm(203 accessions)have been genotyped for 18 microsatellite loci, and phenotyped for 24 economic traits. The results of this analyses & a poster presentation of the current status of genetic diversity & conservation of walnut in Azerbaijan were presented at the 6th Intl. Walnut Symposium-Australia. Manuscripts of these studies were submitted to Acta Horticulturae. Phenotyping of the entire V. vinifera collection for 32 traits of breeding value is in progress. We are collaborating with C. Oven-USDA Geneva & researchers from the Univ. British Colombia on a project to establish the molecular basis for secondary compounds of importance to wine quality. All crop collections inventories have been updated on GRIN and phenotypic data & photographs depicting variability for floral, vegetative & important economic traits have been uploaded during 2009 except for Pistachio, which is being inventoried. Propagation of newly received & existing germplasm accessions continues at the repository for planting of new germplasm and replacement of old accessions that are lost in the field plantings at the Wolfskill Site. Nearly all of the grape, 40% of Prunus & other minor species collections have been backed up. We also have 80% of olive, 40% of pomegranate & fig accessions in sub-irrigation system as backups. Juglans spp. germplasm have been propagated through seed germination for extensive screening for crowngall, nematode, & Phytophthora rots. 300 accessions of grape, 45 of kiwi were moved to the field site at Wolfskill. 5358 germplasm items were distributed to 10 countries. 85% went to U.S. public/private sector breeders, academic institutes, nursery industries, & private growers, a 13% increase over 2008.


4.Accomplishments
1. Acquisition of germplasm. Obtain new acquisitions to fill collection gaps of vine, tree fruit, and nut crop genetic resources adapted to Mediterranean-like climates. Genetic resources of vine tree fruit and nut germplasm adapted to Mediterranean climates need to be acquired for food security with access for researchers and breeders who are developing new crops. The National Clonal Germplasm Repository in Davis, CA acquired 148 accessions of new germplasm through exploration and exchange. For the second year in a row, an exploration in Azerbaijan, especially in the province of Nakchivan during September-mid-October 2008 has yielded many valuable and highly diverse accessions of walnut, stonefruit, and grape. The exploration and exchange with Azerbaijan will provide genetic diversity previously unavailable to US scientists and other horticultural interests.

2. Germplasm distribution. Distribution of plant genetic resources of designated Mediterranean-adapted fruit and nut crops and their wild-species relatives. Genetic resources of vine tree fruit and nut germplasm adapted to Mediterranean climates need to be distributed to researchers and breeders who are developing new crops. Year after year, demand for fruit and nut germplasm is increasing. The National Clonal Germplasm Repository in Davis, CA experienced a nearly 13% increase during 2008-09 over the previous year with distribution exceeding over 5000 accessions. Surprisingly minor crops such as fig and pomegranates are in greater demand than the widely grown species such as grape and stonefruits. Genetic diversity was provided to U.S. scientists and other horticultural interests. This will permit furthering of knowledge regarding genetic diversity and may provide significant new niche crops.

3. Germplasm conservation and management. Conserve and regenerate priority vine, tree fruits, and nut crop genetic resources adapted to Mediterranean-like climates. Genetic resources of vine tree fruit and nut germplasm adapted to Mediterranean climates need to be maintained and preserved for food security with access for researchers and breeders who are developing new crops. At the National Clonal Germplasm Repository in Davis, CA - 413 accessions (41 Actinidia, 53 Diospyros, 30 Morus, 41 Prunus, and 248 Vitis accessions) representing the new germplasm introductions and some of the re-propagations have been planted in the Wolfskill Field Collections. Unit had 85 new germplasm introductions from 2007-08 Azerbaijan exploration have been successfully propagated and established in greenhouses at Davis and the successfully re-propagated most of the fig collection to establish a new germplasm block was accomplished. These accomplishments help guarantee that these important accessions will continue to be available to U.S. research and agricultural interests.

4. Germplasm characterization. Characterize (“genotype”) and evaluate (“phenotype”) priority vine, tree fruit, and nut crop genetic resources adapted to Mediterranean-like climates for molecular markers and key horticultural traits such as adaptation and product quality. Genetic resources of vine tree fruit and nut germplasm adapted to Mediterranean climates need to be characterized for researchers and breeders who are developing new crops. The entire cultivated grape accession have been genotyped for eight microsatellite loci by researchers at the National Clonal Germplasm Repository, and data indicated nearly 65% of accessions exhibited unique multilocus genotypes suggesting extensive variation in the collection. Analyses of walnut genetic structure and differentiation revealed a significant genetic variation in the collection but with simple genetic structure appropriate for association genetic analysis. Genetic characterization of olive collection indicated extensive polymorphisms with simple structure and permitted identification of many synonyms in the collection. Greater understanding of accession characteristics will enhance value of accessions to researchers and permit them to make greater progress by quickly identifying the material most appropriate to their efforts.


6.Technology Transfer

None

Last Modified: 7/30/2014
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