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Kazumi Hosoya Hiroshi Ashiwa Masakazu Watanabe Ken-ya Mizuguchi Toshio Okazaki 《Ichthyological Research》2003,50(1):0001-0008
Two biological types of Japanese dark chub, so-called types A and B of Zacco temminckii, were taxonomically inspected. A comparison of types A and B with the lectotypes of Leuciscus sieboldii and L. temminckii in Siebold's collection revealed that type A is identical to L. sieboldii, whereas type B matches L. temminckii. Hence, Zacco sieboldii and Z. temminckii were redescribed on the basis of the lectotype and additional specimens from Japan. Zacco sieboldii is distinguishable from Z. temminckii by having a narrower band on the anterior portion of both body sides, nine branched rays of anal fin (10 in Z. temminckii), lateral line scales not less than 53 (not more than 52 in Z. temminckii), and scales above lateral line not less than 13 (not more than 11 in Z. temmincki). A key to the species of Japanese Zacco is also provided.
Received: August 15, 1999 / Revised: July 25, 2002 / Accepted: August 19, 2002
Acknowledgments We express our cordial thanks to all the following investigators: Dr. M.J.P. Van Oijen (RMNH) for the specimen loan of von
Siebold's collection; Professor San-Rin Jeon, Sang-Myung University (formerly, Seoul) for providing several papers on Korean
Zacco congeners; Dr. Harumi Sakai, National Fisheries University; Dr. Tetsuo Furukawa-Tanaka, Museum of Nature and Human Activities,
Hyogo; Dr. Seishi Kimura, Mie University; Dr. Akihisa Iwata, Kyoto University; Dr. Osamu Katano, National Research Institute
of Fisheries Sciences; Mr. Kazuo Hoshino, Oita Marine Palace; and Dr. Kouichi Kawamura, National Research Institute of Aquaculture,
for the valuable comments and information on the ecological aspects of both species of the Japanese dark chub.
Correspondence to:Kazumi Hosoya 相似文献
3.
In previous studies we reported that while core populations of Sitka spruce [Picea sitchensis (Bong.) Carr] have little within-population genetic structure, peripheral populations are strongly spatially structured at
distances up to 500 m. Here we explore the implications of this difference in structure on ex situ gene conservation collections
and estimates of genetic diversity from research collections. We test the effects of varying the number of individuals sampled
and the total area they are sampled across on capture of neutral genetic variation in collections from core, continuous versus
peripheral, disjunct populations. Bivariate response surface analysis of genetic marker data for eight sequence tagged site
loci from core and peripheral populations suggest that a population sample from 150 trees covering at least 225 ha would be
adequate for capturing 95% of the genetic diversity (as measured by allelic richness or expected heterozygosity) in core populations.
However, a larger sample of 180 individuals from an area of at least 324 ha is needed in peripheral populations to capture
the same proportion of standing variation because of stronger within-population spatial genetic structure. Standard population
sampling protocols for estimating among and within-population genetic diversity would significantly underestimate the within-population
allelic richness and expected heterozygosity of peripheral but not core populations, potentially leading to poor representation
of genetic variation in peripheral populations as well as erroneous conclusions about their genetic impoverishment. 相似文献
4.
Ryuji Uesugi Jun Nishihiro Yoshihiko Tsumura Izumi Washitani 《Conservation Genetics》2007,8(1):111-121
Populations of a threatened aquatic plant, Nymphoides peltata, have rapidly degenerated under the influence of recent artificial changes in Lake Kasumigaura of Japan. To estimate the
potential of soil seed banks for genetic restoration of the species, we used 10 microsatellite markers to analyze the genetic
variation in adults and in seedlings that emerged from soil seed banks. About 187 leaf samples from the cultured stocks that
were collected in 17 adult subpopulations in 1995 and 2000 and from three subpopulations that were newly discovered in 2002
were analyzed. As a result, only 18 genets could be identified, suggesting that clonal diversity of the adult population had
already become extremely low. Genetic tests were performed on 430 seedlings from seed banks at six locations of natural lakeshores
and three of the restoration sites that were artificially constructed in an attempt to assign them to the remnant adult population;
many of the seedlings showed genetic variation different from the adults. Furthermore, the seedlings preserved seven alleles
that had been lost from remnant adults. However, they had lower average numbers of alleles and heterozygosity levels (NA = 1.5–3.1,
H
E = 0.146–0.487) than the remnant adults (NA = 3.5, H
E = 0.539) and showed high inbreeding coefficients, suggesting that the seed banks were produced by inbreeding. Thus, although
the seed banks had a certain potential to restore genetic diversity, the fitness reduction in seed banks caused by inbreeding
could affect the success of restoration based on seed banks. 相似文献
5.
Cypripedium macranthos var. rebunense is an endangered plant endemic to Rebun Island, Japan. A proper understanding of genetic diversity is needed when conducting
conservation programs for rare and endangered species. We therefore examined the genetic diversity of C. macranthos var. rebunense using allozyme markers with a view to future conservation. Our study revealed that C. macranthos var. rebunense has relatively high genetic diversity (P was 0.62, n
a and n
e were 1.85 and 1.28 respectively, and H
o and H
e were 0.163 and 0.187, respectively) when compared with other plant taxa. The natural habitats of C. macranthos var. rebunense are geographically separated into northern and the southern populations. Disappearance of alleles and increase in homozygosity
expected as a result of the bottleneck effect were observed, particularly in the southern populations composed of a small
number of plants. As additional negative effects (inbreeding depression and further genetic drift) due to fragmentation are
predicted in these populations, the southern populations may show deterioration of genetic diversity in the near future. 相似文献
6.
The relationship between Sporidiobolus johnsonii and S. salmonicolor was investigated using rDNA sequence data. Two statistically well-supported clades were obtained. One clade included the
type strain of S. johnsonii and the other included the type strain of S. salmonicolor. However, some mating strains of S. salmonicolor were found in the S. johnsonii group. These strains belonged to mating type A2 and were sexually compatible with mating type A1 strains from the S. salmonicolor group. DNA–DNA reassociation values were high within each clade and moderate between the two clades. In the re-investigation
of teliospore germination, we observed that the basidia of S. salmonicolor were two-celled. In S. johnsonii, basidia were not formed and teliospore germination resulted in direct formation of yeast cells. We hypothesize that the
S. johnsonii clade is becoming genetically isolated from the S. salmonicolor group and that a speciation process is presently going on. We suspect that the observed sexual compatibility between strains
of the S. johnsonii and S. salmonicolor groups and the possible genetic flow between the two species has little biological relevance because distinct phenotypes
have been fixed in the two taxa and intermediate (hybrid) sequences for LSU and ITS rDNAs have not been detected.
An erratum to this article can be found at 相似文献
7.
Micropropagation was assessed as an ex situ conservation strategy for the endangered Australian plant Pimelea spicata (Thymelaeaceae). Although regeneration of this species was achieved, several physiological problems were observed and examined. Explants of P. spicata had a higher multiplication rate on MS medium, than on ½ MS, but there was a significantly higher percentage of necrotic shoot tips on the higher salt medium. Increasing calcium concentration and gas exchange exacerbated shoot-tip necrosis. A number of hyperhydrated shoots were produced in all treatments, the cause of which could not be determined, although less hyperhydicity was observed in the ½ MS treatment. Shoots, rooted in vitro on ½ MS in the absence of plant growth regulators, were successfully acclimatised to greenhouse conditions, while direct rooting of microshoots using IBA gel treatment proved unsuccessful. This is the first report of tissue culture propagation of this endangered species. 相似文献
8.
We examined the genetic population structure of Lefua echigonia (Japanese name, hotoke-dojo) using polymerase chain reaction restriction-fragment length polymorphisms (PCR-RFLPs) of the mitochondrial cytochrome b gene and two allozymic loci. The phylogenetic relationships of L. echigonia and those among L. echigonia, Lefua sp. (nagare hotoke-dojo), and L. nikkonis (ezo hotoke-dojo) were also investigated based on the nucleotide sequences of the cytochrome b gene. PCR-RFLP analysis revealed 18 mitotypes in L. echigonia, 2 in Lefua sp., and 1 in L. nikkonis. Phylogenetic trees based on the cytochrome b sequences indicated that the 18 mitotypes in L. echigonia were divided into five distinct groups (South-Kanto, North-Kanto, Tohoku, Echigo, and Tokai-Kinki clades) that differed by 8.5–15.3%, reflecting region-specific geographic distributions. The distributions of alleles in two allozymic loci roughly corresponded to those of the mitotype groups. The divergence times of the five groups were estimated to be about 3.4–7.7 million years ago by applying a general rate for mitochondrial DNA, suggesting that the divergence among them might have occurred in the late Tertiary. It can be inferred that the regional differentiation of each group was mainly due to geographic isolation and that this has been maintained, because the boundaries among the groups corresponded to geological features. The trees also supported the existence of three taxa, L. echigonia, Lefua sp., and L. nikkonis. We concluded that Lefua sp. was distinguished from other species in Lefua by morphological and ecological characters and also by genetic divergences of the cytochrome b gene. Our study also demonstrated the superior efficacy and simplicity of PCR-RFLP analysis as a method for detecting genetic variation in L. echigonia. 相似文献
9.
Hiroyuki Motomura Sven O. Kullander Tetsuo Yoshino Yukio Iwatsuki 《Ichthyological Research》2002,49(4):307-317
A taxonomic review of seven-spined Polynemus species recognizes two species as valid: P. hornadayi Myers, 1936, currently known only from western Sarawak, Kalimantan, Malaysia, and P. paradiseus Linnaeus, 1758, distributed from India to Thailand and regarded as a senior synonym of P. aureus Hamilton, 1822, P. longifilis Cuvier in Cuvier and Valenciennes, 1829, P. risua Hamilton, 1822, and P. toposui Hamilton, 1822. Polynemus hornadayi differs from P. paradiseus in having a strongly protruded occipital profile (vs. nearly straight in the latter), lower counts of anal fin soft rays (mode 11 vs. 12) and gill rakers (26 vs. 32 or 33), higher counts of pectoral fin rays (18 vs. 17), scales above and below the lateral line (11 and 18 vs. 7 and 11, respectively), and pored lateral line scales (94 vs. 70), the fifth pectoral filament longest (vs. sixth), the fourth pectoral filament longer (extending well beyond the posterior central margin of the caudal fin vs. not reaching posterior central margin), a longer pectoral fin ray (posterior tip of pectoral fin reaching to midpoint of anal fin base vs. not reaching), a deeper maxilla posterior margin (mean 5% of SL vs. 4% of SL), and a well-developed swimbladder (vs. absent). 相似文献
10.
We investigated the genetic structure of Miscanthus sinensis ssp. condensatus on Miyake Island, which was devastated by a volcanic eruption in 2000, by amplified fragment length polymorphisms (AFLPs) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for chloroplast DNA (cpDNA) variation, to develop recommendations for the revegetation of devastated sites. Genetic differentiation among populations was significant, and five populations were classified into three regional groups. The aspect ratios of leaf-blades varied significantly among populations, but both geographical proximity and morphological similarities did not precisely reflect genetic similarities. In the airport population, we found a rare haplotype that may have been transmitted from outside the island. These findings will assist the revegetation of the island. 相似文献
11.
Akihisa Torii Antony S. Harold Takakazu Ozawa Yukio Iwatsuki 《Ichthyological Research》2003,50(2):129-139
This study redescribes Bregmaceros mcclellandi Thompson, 1840, based on one specimen (74.4 mm SL) from the Bay of Bengal and 66 specimens (30.0–84.7 mm SL) from Mumbai
(Bombay), India, because the type specimens have apparently been lost. The present specimens are characterized by having black
dorsal, pectoral, and caudal fins and show the following morphology: caudal fin slightly forked; body chromatophores present
mainly at the dorsal part; no scales on cheek; vertebrae 52–55 (13–15 + 38–41); dorsal rays 52–59; anal rays 54–60; pectoral
rays 18–20; caudal rays 27–31 (principal rays 14); transverse scales 14–15. In the 66 Mumbai specimens, it was confirmed that
the distinctive black fin pigmentation developed sequentially with growth, with complete pigmentation first on the anterior
lobe of the dorsal fin, then simultaneously on the posterior lobe of the dorsal fin, the caudal fin, and the pectoral fin,
and last, on the anal fin. This species is known only from the Arabian Sea, Bay of Bengal, and Gulf of Thailand. A review
of 16 nominal Bregmaceros species indicates that, besides B. mcclellandi, the distinctive dark fin pigmentation is found in B. atripinnis (Tickell), B. atlanticus Goode and Bean, B. japonicus Tanaka, and B. lanceolatus Shen. B. atripinnis is considered a junior synonym of B. mcclellandi, and the others are clearly distinct from B. mcclellandi. Comments are made on some of the characters to more fully characterize the species and for reference in future revisionary
and phylogenetic studies.
Received: June 17, 2002 / Revised: December 2, 2002 / Accepted: December 24, 2002 相似文献
12.
Bettina Heider Meike S. Andersson Rainer Schultze-Kraft 《Biodiversity and Conservation》2007,16(6):1617-1631
Flemingia macrophylla (Willd.) Kuntze ex Merr., a multi-purpose legume with potential as dry-season forage crop, mainly occurs in subhumid to humid
environments of tropical and subtropical Asia. Despite increasing interest in conservation of germplasm suitable for low-input
production systems information on the genetic diversity of F. macrophylla is extremely scarce. The creation of baseline data is supposed to contribute to more efficient conservation management and
to identify collecting strategies of novel germplasm. Random amplified polymorphic (RAPD) markers were used to investigate
the genetic variation among 37 F. macrophylla accessions. Germplasm analysed in this study originated from Bac Kan province, Northeast Vietnam. Eight primers generated
a total of 47 amplified RAPD loci of which 38 were polymorphic. Jaccard’s similarity coefficients among accessions ranged
from 0.069 to 1 with a mean of 0.67. The UPGMA dendrogram revealed three clusters along with three outliers. No correspondence
between geographic and genetic distance was found (Mantel test: R = 0.21; P = 0.016). Analysis of molecular variance (AMOVA) revealed significant (P < 0.001) differentiation between accessions collected in lowland and upland regions. Results of UPGMA clustering were confirmed
by the pattern of principle coordinates analysis (PCO) plotting. Future collecting strategies should target populations at
large distances and along the altitudinal range. Ex situ conservation should encompass those accessions that showed genetic
divergence. In situ conservation may consist of establishing a system of interconnected population fragments to guarantee
continuing genetic exchange via corridors and of rehabilitating degraded habitats. 相似文献
13.
The maintenance of genetic diversity is one of the chief concerns in the captive breeding of endangered species. Using microsatellite and mtDNA markers, we examined the effects of two key variables (parental number and duration of breeding period) on effective population size (Ne) and genetic diversity of offspring in an experimental breeding program for the endangered Tokyo bitterling, Tanakia tanago. Average heterozygosity and number of alleles of offspring estimated from microsatellite data increased with parental number in a breeding aquarium, and exhibited higher values for a long breeding period treatment (9 weeks) compared with a short breeding period (3 weeks). Haplotype diversity in mtDNA of offspring decreased with the reduction in parental number, and this tendency was greater for the short breeding period treatment. Genetic estimates of Ne obtained with two single‐sample estimation methods were consistently higher for the long breeding period treatment with the same number of parental fish. Average Ne/N ratios were ranged from 0.5 to 1.4, and were high especially in the long breeding period with small and medium parental number treatments. Our results suggest that the spawning intervals of females and alternative mating behaviors of males influence the effective size and genetic diversity of offspring in bitterling. To maintain the genetic diversity of captive T. tanago, we recommend that captive breeding programs should be conducted for a sufficiently long period with an optimal level of parental density, as well as using an adequate number of parents. Zoo Biol 31:656‐668, 2012. © 2011 Wiley Periodicals, Inc. 相似文献
14.
In vitro propagation of Rhododendron ponticum L. subsp. baeticum, an endangered species present in limited and vulnerable populations as a Tertiary relict in the southern Iberian Peninsula, was attained. Several cytokinin:IAA ratios and a range of zeatin concentrations were evaluated for their effect on shoot multiplication from apical shoots and nodal segments. The type of cytokinin and the origin of the explant were the most important factors affecting shoot multiplication. The highest shoot multiplication rate was obtained from single-nodal explants on medium supplemented with zeatin. Increasing zeatin concentration promotes shoot multiplication independently of explant type, although this effect tends to decrease with higher zeatin concentration. Shoot growth was higher in apical shoots and it was not stimulated by the presence of auxin. A number of experiments were conducted to identify suitable procedures for rooting of in vitro produced shoots. The best results in terms of in vitro rooting were obtained with Andersons modified medium with macrosalts reduced to one-half, regardless of the auxin or its concentration in the medium. Although rooting frequency rose to 97% by basal immersion of shoots in auxin concentrated solution followed by in vitro culture on an auxin-free medium, the survival of the plants after 6 months of acclimatization was poor (50%). Best results (100% rooting and survival) were observed for ex vitro rooting. The micropropagated plants from this study were successfully reintroduced into their natural habitat (87% of survival after 8 months). 相似文献
15.
Marjan Khalili Mahani Nobuyuki Inomata Alireza Saboori Baraldin Ebrahim Sayed Tabatabaei Hiroko Ishiyama Ardeshir Ariana Alfred E. Szmidt 《Experimental & applied acarology》2009,48(4):273-289
Allothrombium
pulvinum Ewing is a common natural enemy of aphids and some other arthropods. So far, there are no studies that have addressed genetic
variation of this predatory mite. We investigated genetic variation of A. pulvinum across its whole known range in Iran. A 410 bp portion of the mitochondrial cytochrome c oxidase subunit I gene (coxI) and 797–802 bp portion of the internal transcribed spacer 2 of rDNA (ITS2) were sequenced for 55 individuals from 11 populations, resulting in 12 and 26 haplotypes, respectively. In the coxI region, haplotype and nucleotide diversities varied among populations from 0.00 to 0.90 and from 0.0000 to 0.0110, respectively.
In the ITS2 region they varied from 0.20 to 0.91 and from 0.0006 to 0.0023, respectively. For both gene regions the highest haplotype
and nucleotide diversities were detected in population Mahmoud Abad from northern Iran. Statistically significant population
differentiation (F
ST) was detected in most pair-wise population comparisons. The results of population differentiation for both gene regions were
generally congruent indicating that A. pulvinum from Iran consists of genetically different populations. This suggests that A. pulvinum comprises at least two geographically distinct populations or even more than one species. This study is an initial step towards
understanding genetic variation of A. pulvinum, a taxon for which little molecular information is available. More intensive sampling and analysis of additional DNA regions
are necessary for more detailed classification of this taxon. 相似文献
16.
Genetic differences among 18 Lentinula edodes strains isolated from a fallen trunk of Quercus mongolica var. grosseserrata were characterized by mating tests and restriction fragment length polymorphism (RFLP) analyses of mitochondrial DNA (mtDNA). These strains could be divided into six genets of different mating types. Because the mtDNA of the 18 strains showed four different RFLP genotypes, these strains seemed to have originated from at least 4 distinct parental strains. Strains belonging to the same genet were collected from fruiting bodies located not more than about 1m apart on the fallen tree. Implications of these findings regarding the degree of genetic variation and territory sizes of individual genets of wood-decaying basidiomycetes such as L. edodes are discussed. 相似文献
17.
Features of otoliths in Opsaridium microcephalum juveniles were observed, and the increment formation pattern was validated using Alizarin Complexone (ALC). The sagitta was
arrowhead shaped with an obvious core and rostra, the latter being fragile and easily destroyed by extracting and grinding
processes. Increments around the core were readable but not in the rostra. The asteriscus was oval shaped with an ambiguous
core leading to difficulty in discerning the first increment. The lapillus was round and fan shaped with an obvious core.
Increments in the lapillus were clearly deposited from the core to the margin. These features made the lapillus the most appropriate
for reading otolith increments. Increments counts in the lapillus formed after ALC treatment agreed with days elapsed, showing
the daily formation of increments. Consequently, the lapillus is only appropriate for daily increment analysis in Opsaridium microcephalum.
Received: December 4, 2001 / Revised: August 14, 2002 / Accepted: September 11, 2002
Acknowledgments The authors express great thanks to J.S. Likongwe and E. Kaunda, Department of Aquaculture and Fisheries Science, Bunda College
of Agriculture, University of Malawi, for their advisory comments. The authors are also grateful to the Japan International
Cooperation Agency (JICA) for giving us an opportunity to work on this subject.
Correspondence to:Shinsuke Morioka 相似文献
18.
The Japanese squirrel (Sciurus lis) is endemic to Honshu and Shikoku, Japan. In suburban environments this squirrel has tended to disappear from smaller and/or
more isolated woodlots. In this study, genetic structure was compared from 1999 to 2004 for two subpopulations, one in a continuous
mountain forest of western Tokyo and the other in a neighbouring woodlot isolated by a busy road. By sequencing 434 bp of
the mitochondrial DNA control region of all 69 squirrels living in the two habitats, nine haplotypes were detected. Both the
number of haplotypes and their genetic diversity were lower in the isolated woodlot (5 and 0.62, respectively) than in the
continuous forest (8 and 0.79). Yearly comparisons revealed that only two to three haplotypes occurred simultaneously in the
isolated woodlot whereas four to six were always found in the continuous forest, although the number of resident squirrels
per year did not differ between the two sites. Haplotype dynamics revealed that the female population in the isolated woodlot
was in a monotypic state for over two years before immigration of females with different haplotypes occurred. In the isolated
woodlot immigration was thus restricted and turnover was lower, particularly among females. Such demographic factors seem
to maintain the lower genetic diversity of the isolated subpopulation. 相似文献
19.
Teruyuki Matsumoto Yasushi Obatake Yukitaka Fukumasa-Nakai Eiji Nagasawa 《Mycoscience》2003,44(3):197-202
20.
Summary The generation of transgenic Cucumis sativus cv. Greenlong plants resistant to phosphinothricin (PPT) was obtained using Agrobacterium tumefaciens-mediated gene transfer. The protocol relied on the regeneration of shoots from cotyledon explants. Transformed shoots were
obtained on Murashige and Skoog medium supplemented with 4.4 μM 6-benzylaminopurine 3.8 μM abscisic acid, 108.5 μM adenine sulfate, and 2 mg l−1 phosphinothricin. Cotyledons were inoculated with the strain EHA105 harboring the neomycin phosphotransferase II (npt II), and phosphinothricin resistance (bar) genes conferring resistance to kanamycin and PPT. Transformants were selected by using increasing concentrations of PPT
(2–6 mg l−1). Elongation and rooting of putative transformants were performed on PPT-containing (2 mg l−1) medium with 1.4 μM gibberellic acid and 4.9 μM indolebutyric acid, respectively. Putative transformants were confirmed for transgene insertion through PCR and Southern
analysis. Expression of the bar gene in transformed plants was demonstrated using a leaf painting test with the herbicide Basta. Pre-culture of explants
followed by pricking, addition of 50 μM acetosyringone during infection, and selection using PPT rather than kanamycin were found to enhance transformation frequency
as evidenced by transient β-glucuronidase assay. Out of 431 co-cultivated explants, 7.2% produced shoots that rooted and grew
on PPT, and five different plants (1.1%) were demonstrated to be transgenic following Southern hybridization. 相似文献