Seasonal races of chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> and their interrelations in Kamchatka Rivers

Dates of migration and spawning, size-age structure, and fecundity of seasonal races of chum salmon Oncorhynchus keta from the Kol River are reviewed, those of early summer, late summer, and autumn races, as well as localization and structure of their spawning grounds, bed-sediment particle size in the redds, hydrological and thermal conditions on spawning grounds, and meristic characters of races. Special traits of reproduction of seasonal races within the species range and in Kamchatka in particular are discussed. The number of seasonal races in rivers depends on the presence of various habitats suitable for spawning. In rivers with complicated hydrogeomorphological structure, the number of seasonal races increases. Variations of types of seasonal races in a particular river and in the whole species area are epigenetic, i.e., they depend on the hereditary genetic program and presence of conditions providing its realization via various channels.     

A search for null alleles at the microsatellite locus of chum salmon (<Emphasis Type="Italic">Oncorhynchus keta</Emphasis> Walbaum)

Population studies with the use of microsatellite markers face a problem of null alleles, i.e., the absence of a PCR product, caused by the mutations in the microsatellite flanking regions, which serve as the sites of primer hybridization. In this case, the microsatellite primer associated with such mutation is not amplified, leading to false homozygosity in heterozygous individuals. This, in turn, results in biased population genetic estimates, including the excess of homozygotes at microsatellite loci. Analysis of the population structure of a Pacific salmon species, chum salmon (Oncorhynchus keta Walbaum), revealed the presence of null alleles at the Oke3 microsatellite locus in the population samples, in which an excess of homozygotes was observed. The analysis was performed using different combinations of modified primers chosen to match the Oke3 locus. The use of these primers enabled identification of true heterozygotes among those individuals, which were previously diagnosed as homozygotes with the use of standard primers. Removal of null alleles eliminated the excess homozygotes in the chum salmon samples described. In addition to the exclusion of false homozygosity, the use of modified primers makes it possible to introduce polymorphic primer variants associated with certain microsatellite alleles into population studies.     

Genetic variability in anadromous fishes,chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> (Walbaum, 1792), and Sakhalin taimen <Emphasis Type="Italic">Parahucho perryi</Emphasis> (Brevoort, 1856) from the Northwestern Pacific as a reflection of paleoclimate oscilations

The genetic variability distribution of two mtDNA segments of chum salmon (Oncorhynchus keta) (Walbaum, 1792) and Sakhalin taimen (Parahucho perryi) (Brevoort, 1856) was examined in populations of the Sea of Japan and the Sea of Okhotsk. The values of haplotype and nucleotide variability in these species are, in general, of the same level. The dating of the divergence time of species haplotypes revealed four evolutionary periods in Sakhalin taimen and three in chum salmon. In the taimen, the first divergence time occurred approximately 430 thousand years (kyr) ago, the second 220 kyr ago, and the third 70 kyr ago. In the chum salmon, the first divergence time corresponds to 220 kyr; the second is approximately 100 kyr ago. In both species, the main portion of presently revealed haplotypes evolved over the past 50–10 kyr. Certain glacioeustatic sea level fluctuations influenced each stage of evolution history of species, contributing to their geographic isolation. Demographic population history research found that the initial stage of population growth in the taimen occurred at the time period of approximately 12 kyr ago and was apparently associated with the end of the Last Glacial Maximum. In the chum salmon, this period began somewhat earlier, 30–35 kyr ago; it has accelerated in the past 10–15 kyr. The last glaciation to a lesser extent impacted the demographics of chum salmon, probably due to the greater eurythermity and to the larger range of this species.     

The genetic structure of chum salmon (<Emphasis Type="Italic">Oncorhynchus keta</Emphasis> Walbaum) populations inferred from the nucleotide variation of the mitochondrial DNA cytochrome <Emphasis Type="Italic">b</Emphasis> gene

The nucleotide sequences of a fragment of the mitochondrial DNA cytochrome b gene were determined in 12 chum salmon populations from the Russian Far East. The level of genetic diversity in the chum salmon populations from the Iturup Island, northern coast of the Sea of Okhotsk, and Anadyr’ River was found to be higher than in the populations from Kamchatka and Sakhalin, which may be related to the history of their origin and dispersal. The proportions of intrapopulation genetic variability (F _CT) and interpopulation genetic variability within the groups (F _SC) account for 90.87 and 0.9%, respectively, and the intergroup component (F _ST) comprises 8.23%. The predominance of one haplotype, B1, which is common for all populations studied, and a low share of intergroup variability suggest the beginning of colonization by the species of the given region from a common source (group of founders) and a relatively recent time of divergence of the chum salmon populations from the region examined.     

Patterns of genetic diversity in population complexes of pacific chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> Walbaum,from Asia and America,inferred from allozyme polymorphism data

Based on the data of Russian and foreign researchers, a database, consisting of 100 allozyme-coding loci examined in 288 chum salmon populations from Asia and Northern America, was constructed. Using G-test, genetic heterogeneity of Asian population samples of chum salmon was evaluated. Correlations between the frequencies of major alleles and geographic latitude of the mouths of native rivers were estimated. Using the methods of Nei and Cavalli-Sforza and Edwards, for different local chum salmon stock groups the genetic distances at the number of polymorphic enzyme loci were determined. Analysis of these distances made it possible to evaluate the patterns of genetic diversity in regional population groups from the Russian Far East, Japan, and North America. The proportions of genetic variation at each hierarchical level, identified in accordance with the geographical positions of the populations, were estimated through partitioning of variation in Asian populations into within and between-population components. It was demonstrated that intraspecific genetic structure of chum salmon corresponded geographic subdivision into regional population groups.     

Geographic variation and temporal population differentiation of chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> from some regions of the Russian Far East

Allozyme variation of chum salmon Oncorhynchus keta was examined in the populations from nine rivers of the Russian Far East. A total of 12 loci were tested, and eight of these were shown to be polymorphic. The greatest contribution to the samples differentiation was made by the EST-D1* and sIDHP-2* loci. Most of the allele diversity was distributed among the individuals within the samples. The among-sample differences within races were statistically significant and accounted for slightly more than 7% of total variation. The differences between the races constituted 0.1% and were statistically nonsignificant. Genetic similarity of seasonal races within single locality allowed suggestion on their secondary formation after settling of founder population into a certain region.     

Feeding and daily ration of the chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> in the western Bering Sea in the summer-fall of 2004

This study was based on data on the feeding of the chum salmon Oncorhynchus keta sampled at daily stations in areas of the Navarin Shelf and Aleutian Basin in the Bering Sea in August and September 2004. The food composition and daily dynamics of chum feeding were investigated. The rate of food evacuation from the stomach and the amount of the daily diet were estimated. The distinctions in the feeding patterns of chum sampled from different areas were considered. In the Navarin Shelf area the chumís prey were primarily nekton species (mostly Alaskan pollack underyearlings) and the amount of the daily diet for chum of various size groups was 1.8–3.8% of their body weight. In the deep-water Aleutian Basin, the daily dynamics of chum feeding depended on migration of euphausiids, amphipods and mesopelagic fishes to the surface water layers of epipelagics during the night. The daily ration for chum that fed mainly on plankton did not exceed 2.6–2.8% of their body weight in August and 1.2–2.5% in September.     

Variation of mitochondrial DNA in chinook salmon <Emphasis Type="Italic">Oncorhynchus tschawytscha</Emphasis> Walbaum populations from Kamchatka

The variation in mitochondrial DNA (mtDNA) structure among chinook salmon Oncorhynchus tschawytscha Walbaum populations from Kamchatka was inferred from restriction length polymorphism analysis using eight restriction endonucleases. The nucleotide sequence variation in three amplified mtDNA regions was examined at seven polymorphic restriction sites in 579 fish from 13 localities. Based on the frequencies of 11 combined haplotypes and the number of nucleotide substitutions, the among-and within-population variation was estimated. The heterogeneity test showed highly significant differences among all the populations. The estimated maximum time of independent divergence of the asian chinook salmon populations, whose differences was about 0.02% nucleotide substitutions, did not exceed 10 000–20 000 years. Apparently, the retreat of the late Pleistocene glacier triggered spreading, recolonization, and formation of the present-day pattern of the species subdivision into structural components.     

<Emphasis Type="Italic">Ty</Emphasis>1<Emphasis Type="Italic">/copia</Emphasis>- and <Emphasis Type="Italic">Ty</Emphasis>3<Emphasis Type="Italic">/gypsy</Emphasis>-like DNA sequences in <Emphasis Type="Italic">Helianthus </Emphasis>species

Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.     

<Emphasis Type="Italic">Galleria</Emphasis><Emphasis Type="Italic">mellonella</Emphasis> are Resistant to <Emphasis Type="Italic">Pneumocystis</Emphasis><Emphasis Type="Italic">murina</Emphasis> Infection

Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.     

Revision of the <Emphasis Type="Italic">Serrulati</Emphasis> species of <Emphasis Type="Italic">Penstemon</Emphasis> section <Emphasis Type="Italic">Saccanthera</Emphasis> subsection <Emphasis Type="Italic">Serrulati</Emphasis>

A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.     

<Emphasis Type="Italic">Agrobacterium</Emphasis><Emphasis Type="Italic">tumefaciens</Emphasis>-mediated transformation of callus cells of <Emphasis Type="Italic">Crataegus</Emphasis><Emphasis Type="Italic">aronia</Emphasis>

A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l⁻¹ Indole-3-butyric acid (IBA) and 0.5 mg l⁻¹ 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l⁻¹ 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l⁻¹ kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l⁻¹ hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.     

Chinook salmon (<Emphasis Type="Italic">Oncorhynchus tshawytscha</Emphasis>, Walbaum 1792) in the Beagle Channel,Tierra del Fuego: the onset of an invasion

In this paper we provide the first report of the presence of exotic Chinook salmon (Oncorhynchus tshawytscha) in two rivers off the Beagle Channel, Lapataia and Ovando, in southern Tierra del Fuego. We also confirm that successful reproduction occurred in the fall of 2007, as we captured yearlings in freshwater. Scale pattern analyses of adult fish caught were all of the “stream” ecotype, with ages ranging between 3 and 5 (average 4.2 year). Stable isotope analysis of Ovando-Lapataia Chinook population indicates general patterns consistent with those of other populations in the region, but characteristically enriched levels of C indicates a distinct ocean feeding location as compared to Atlantic populations in the Santa Cruz River. Two different haplotypes, one identical to the unique haplotype of the Caterina River population, were found in the Ovando-Lapataia rivers, providing partial evidence for some level of contemporary segregation between these two populations. As an exotic species, Chinook salmon have been able to use the ocean as a waterway to rapidly colonize new habitats both in New Zealand and in several Pacific and Atlantic river basins of continental Patagonia. This record expands the known distribution of this species in Patagonia further south and into the Island of Tierra del Fuego. Its presence in the Beagle Channel creates the conditions for its expansion to a significant collection of new rivers, as well as to adjacent marine areas in and around the Southern Fuegian Channels. Our results provide support to the idea that, in practice, no district of Patagonia is sheltered from the colonization by invasive anadromous Salmonids.     

A new methanol assimilating yeast, <Emphasis Type="Italic">Ogataea</Emphasis><Emphasis Type="Italic">parapolymorpha</Emphasis>, the ascosporic state of <Emphasis Type="Italic">Candida</Emphasis><Emphasis Type="Italic">parapolymorpha</Emphasis>

Ogataea parapolymorpha sp. n. (NRRL YB-1982, CBS 12304, type strain), the ascosporic state of Candida parapolymorpha, is described. The species appears homothallic, assimilates methanol as is typical of most Ogataea species and forms hat-shaped ascospores in asci that become deliquescent. O. parapolymorpha is closely related to Ogataea angusta and Ogataea polymorpha. The three species can be resolved from gene sequence analyses but are unresolved from fermentation and growth reactions that are typically used for yeast identification. On the basis of multiple isolates, O. angusta is known only from California, USA, in association with Drosophila and Aulacigaster flies, O. parapolymorpha is predominantly associated with insect frass from trees in the eastern USA but O. polymorpha has been isolated from various substrates in the USA, Brazil, Spain and Costa Rica.     

Origin of juvenile chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> (Salmonidae) in the Sea of Okhotsk coastal waters off South Sakhalin

Based on the data of the analysis of distribution of juvenile chum salmon Oncorhynchus keta that were marked at salmon hatcheries in the southern part of the Sakhalin Island and Japan it has been established that their stocks in the Sea of Okhotsk coastal waters off South Sakhalin and Japan are of mixed origin. One part of the stock is composed of juveniles from hatcheries located in the southern part of Sakhalin, and the other part is composed of migrants from the waters adjacent to Japan. The first part is formed by juveniles both from hatcheries on the Sea of Okhotsk and Sea of Japan coasts of South Sakhalin. The second part is formed by juveniles reared at hatcheries in all regions of Japan: the Pacific and Sea of Okhotsk coasts of Honshu and Hokkaido, and from the Sea of Okhotsk coast of Hokkaido and Izmena (Nemuro) Strait. In July, in the Sea of Okhotsk coastal waters off South Sakhalin, the length and weight of most juvenile chum salmon of Japanese origin exceed 10 cm and 10 g, and juveniles of Sakhalin origin are always smaller than 10 cm and 10 g, which makes it possible to differentiate juveniles in trawl catches.     

Genetic analysis of four wild chum salmon<Emphasis Type="Italic">Oncorhynchus keta</Emphasis> populations in China based on microsatellite markers

Synopsis To assess the genetic variation and population structure of wild chum salmon in China, we analyzed microsatellite loci for populations in the Amur, Wusuli, Suifen Current and the Tumen rivers. We evaluated expected heterozygosity with two estimators of genetic differentiation (F_ST and G_ST) and Nei’s standard genetic distance. The average expected heterozygosity across the 10 loci was 0.65 in the Wusuli River and the Suifen Current River, 0.64 in the Amur River and 0.66 in the Tumen River, The results of this study show that the recent declines in chum salmon have not led to low levels of genetic variability in China. The proportion of inter-population subdivision among chum salmon was between 5.7 and 6.8%. According to the estimator used, the NJ tree based on Nei’s standard genetic distance indicated that there were two different branches (the Sea of Okhotsk branch and the Sea of Japan branch), the Amur River and the Wusuli River populations were closer, while the Suifen Current River and the Tumen River clustered together. The genetic test for population bottlenecks provided no evidence for a significant genetic signature of population decline, which is consistent with the record of the four populations we have in the last few years.     

In planta transformation of <Emphasis Type="Italic">Notocactus scopa</Emphasis> cv. <Emphasis Type="Italic">Soonjung</Emphasis> by <Emphasis Type="Italic">Agrobacterium </Emphasis><Emphasis Type="Italic">tumefaciens</Emphasis>

Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.