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Andrey Sabitov, Kim E. Hummer and Tom Davis

A plant-collecting expedition to Iturup and Sakhalin Islands, Russian Federation, occurred between 21 July and 12 Sept. 2003. Actinidia, Rubus, Ribes, and Vaccinium, as well as seven accessions of strawberries, Fragaria L., were collected. Among them, a wild strawberry, Fragaria iturupensis Staudt, was collected on the eastern slope of Atsonupuri Volcano, Iturup Island, at 630 and 650 m elevation. This species was similar in habit, leaf color and overall appearance to the American strawberry species F. virginiana Mill. Fruits were bright red, oblate spherical, about 1.4 cm in diameter, and had exerted achenes. The native distribution of this species was limited to the middle elevation of the slope of this volcano, and only on Iturup Island. Chromosome counts indicated that these plants were octoploid. Initial DNA fingerprinting aligned this sample with other octoploid species. In addition to this species, samples of F. yezoensis H. Hara (syn. F. nipponica Makino) were collected on Kuibyshewskii Bay of Cape Otlivnoy, Iturup, and near Ujno-Sakhalinsk City, Sakhalin Island. F. iinumae Makino was observed in Ogon'ki Village, Sakhalin Island. This report confirmed the existence of F. iturupensis, the only known native Asian octoploid strawberry, and documented its limited range. Seeds of these strawberry species are available for research by request from the U.S. Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository in Corvallis.

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Kim E. Hummer, Tom Davis, Hiroyuki Iketani and Hiroyuki Imanishi

Genetic resources of temperate berry crops were collected 7 to 27 July 2004 in Hokkaido, Japan, under a bilateral agreement between the United States and Japan. This expedition was a collaborative effort between the United States Department of Agriculture (USDA), the Japanese Ministry of Agriculture, Forestry and Fisheries (MAFF), the University of New Hampshire, and Akita Prefectural College of Agriculture, Japan. Additional assistance was provided by the Hokkaido Governmental Plant Genetic Resources Center, several Forest Research Stations of the Hokkaido University, and private botanists. The expedition obtained 100 accessions encompassing eight genera and 29 species. In all, 84 seedlots, and 23 plants were obtained. The genera collected included: Actinidia, Fragaria, Lonicera, Morus, Ribes, Rubus, Sambucus, and Vaccinium. Plant and seed accessions from this trip are preserved and distributed from the USDA ARS National Clonal Germplasm Repository in Corvallis, Ore., and from MAFF. The target genus for this expedition was Fragaria, so the trip was planned for July. Multiple samples of the two Japanese diploid strawberry species, Fragaria iinumae Makino and F. nipponica Makino (synonym = F. yezoensis H. Hara) were obtained during their prime ripening time. Ribes, Rubus, and Vaccinium fruits ripened later in the summer, but were collected when fruit were observed. Unfortunately, seeds of some of these accessions proved to be immature or nonviable upon extraction. We suggest that expeditions to collect these genera should be planned for late August. Morphological and molecular evaluation of collected germplasm is underway at the USDA ARS Corvallis Repository and at the University of New Hampshire.

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Andrea Quintana, Jana Albrechtova, Tom Davis, Robert J. Griesbach and Rosanna Freyre

Wild Anagallis monelli has blue or orange flowers. Hybrids with red flowers were developed at the Univ. of New Hampshire. Orange is due to pelargonidin, but delphinidin and malvidin can also be present; red is due to delphinidin and malvidin; and blue is due to malvidin only. In this study, blue and orange wild diploid accessions were used to develop four F2 populations (n = 46 to 81). In three populations, segregation ratios supported a previously proposed three-gene model for flower color in this species (P> 0.01). In the fourth population, white flower color was obtained in addition to blue, orange, and red. Molecular studies of genes in the anthocyanin pathway using a candidate gene approach are in progress. In a separate F2 population, blue, violet, lilac, and red flower colors were obtained. One hybrid per color was studied on three replicate plants. Cells with vacuoles containing anthocyanins in upper and lower petal epidermis peels were counted in five flowers per clone using light microscopy (M = 200×). Blue and red hybrids had mostly blue and red cells, respectively, on both surfaces. Lilac and violet hybrids included cells that were blue and intermediate (containing both red and blue) on both surfaces, and also had red cells on the lower epidermis only. Violet hybrids had more blue cells on the upper epidermis than the lilac hybrids. Anthocyanins were determined by HPLC for each petal epidermis in the four flower colors. The blue hybrid had only malvidin in both upper and lower epidermis, and the red hybrid had mainly delphinidin in both surfaces. Lilac and violet hybrids had small amounts (2% and 2.5%, respectively) of delphinidin on upper surfaces, while lower surfaces had 25% to 33% delphinidin.