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1.
Molecular and morphological differences between two geographic populations of Salanx ariakensis (Salangidae) from Korea and Japan 总被引:2,自引:1,他引:1
Geographic variations of a salangid, Salanx ariakensis, from Korea and Japan, based on partial mtDNA cyt b gene sequences and morphometric data, are presented and compared with Salanx cuvieri from China. Analyses of molecular variance (AMOVA) suggested that the two populations of S. ariakensis differed significantly from each other in pairwise fixation index (F
ST = 0.43), although their reciprocal monophyly was not constructed in the phylogenetic analysis. The phylogenetic analysis,
however, supported the reciprocal monophyly of S. ariakensis (Korean population + Japanese population) and S. cuvieri. Differences in genetic structure between the two populations of S. ariakensis were suggested by diversity indices, mismatch distribution shape, and minimum spanning network. In particular, diversity
indices indicated that the Korean population was historically larger and more stable than the Japanese population. In addition,
both the principal component analysis (PCA) and canonical discriminant analysis (CDA) for morphometric characters, and the
Kruskal–Wallis test for some meristic characters, showed that the two populations of S. ariakensis differed from each other, although morphological differences between the two populations of S. ariakensis were smaller than those between S. ariakensis and S. cuvieri. Such morphological differences were consistent with the differences in mtDNA. 相似文献
2.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan. 相似文献
3.
Cupressus chenggiana S. Y. Hu (Cupressaceae) is an endemic and endangered conifer species in southwest China. In order to study the population
genetics and design the effective conservation methods, we aimed to develop microsatellite primers for this species in the
present study. We developed eight new microsatellite loci for this species through biotin capture method. Polymorphism of
each locus was further assessed in 18 individuals from three geographically distant populations. The number of alleles per
locus ranged from 6 to 11 with an average of 8.13. The observed and expected heterozygosities ranged from 0.219 to 0.296 and
from 0.374 to 0.470, with averages of 0.254 and 0.417, respectively. We further found that three of nine microsatellite loci
developed previously for another congeneric species showed polymorphic banding patters. We performed primer-crossing tests
of these loci in the other two congeneric species which are closely related to C. chenggiana (C. gigantea and C. duclouxiana). These microsatellite markers would be effective for analyzing genetic diversity and population genetic structure of this
species and its morphological differentiation with the close relatives. 相似文献
4.
Elizabeth S. MacAvoy Lorna M. McGibbon James P. Sainsbury Hayley Lawrence Carol A. Wilson Charles H. Daugherty Geoffrey K. Chambers 《Conservation Genetics》2007,8(2):305-318
Tuatara (Sphenodon spp) populations are restricted to 35 offshore islands in the Hauraki Gulf, Bay of Plenty and Cook Strait of New Zealand.
Low levels of genetic variation have previously been revealed by allozyme and mtDNA analyses. In this new study, we show that
six polymorphic microsatellite loci display high levels of genetic variation in 14 populations across the geographic range
of tuatara. These populations are characterised by disjunct allele frequency spectra with high numbers of private alleles.
High F
ST (0.26) values indicate marked population structure and assignment tests allocate 96% of all individuals to their source populations.
These genetic data confirm that islands support genetically distinct populations. Principal component analysis and allelic
sequence data supplied information about genetic relationships between populations. Low numbers of rare alleles and low allelic
richness identified populations with reduced genetic diversity. Little Barrier Island has very low numbers of old tuatara
which have retained some relictual diversity. North Brother Island’s tuatara population is inbred with fixed alleles at 5
of the 6 loci. 相似文献
5.
6.
The endangered herb Kirengeshoma palmata, from eastern Asia, has had its population severely reduced in number through habitat loss and fragmentation. All of the
individuals within five subgroups at Mt. Baek-un-san, in the southern part of Korea, were genetically surveyed by allozyme
analysis. Genetic diversity levels within subgroups were relatively high, and a consistently high outcrossing rate as well
as a negligible biparental mating rate were confirmed by this study. Several groups of visibly connected ramets were observed
in a clustered distribution which suggested cloning. Absence of mating partner rather than pollinators decreased seed production
in small mating groups. The present genetic structure of the five subgroups was probably the result of local extinction of
intervening populations. Because K. palmata may be a self-incompatible species, populations with few genets face lowered seed set due to mate scarcity. Thus, this type
of population may be at an increased risk of extinction as a result of inbreeding depression, loss of genetic variability,
and reduced sexual reproduction. The small, genetically depauperate subgroups may need an input of seeds or plants from other
populations in China or Japan in order to regenerate, but the possibility of outcrossing depression leads us to recommend
outbreeding among the local subgroups of Mt. Baek-un-san to restore genetic variability. 相似文献
7.
A pea rust fungus, Uromyces viciae-fabae, has been classified into two varieties, var. viciae-fabae and var. orobi, based on differences in urediniospore wall thickness and putative host specificity in Japan. In principal component analyses, morphological features of urediniospores and teliospores of 94 rust specimens from Vicia, Lathyrus, and Pisum did not show definite host-specific morphological groups. In molecular analyses, 23 Uromyces specimens from Vicia, Lathyrus, and Pisum formed a single genetic clade based on D1/D2 and ITS regions. Four isolates of U. viciae-fabae from V. cracca and V. unijuga could infect and sporulate on P. sativum. These results suggest that U. viciae-fabae populations on different host plants are not biologically differentiated into groups that can be recognized as varieties.Contribution no. 184, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan 相似文献
8.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae. 相似文献
9.
Mycena cupulicola sp. nov. and M. adscendens var. carpophila, new to Japan, are described and illustrated. The former is characterized by having lageniform caulocystidia with a slightly thick-walled broadened base and no cheilocystidia. The latter is characterized by having a white pileus up to 1mm in diameter and narrowly conical caulocystidia. Mycena cryptomeriicola was confirmed to have inamyloid basoidiospores. 相似文献
10.
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
11.
Floral development in three species each of Leptospermum and Kunzea, and one species of Agonis, is described and compared. Differences in the number of stamens and their arrangement in the flower at anthesis are determined by the growth dynamics of the bud. In Leptospermum, early expansion of the bud is predominantly in the axial direction and causes the stamen primordia to be initiated in antepetalous chevrons. In Kunzea, early expansion occurs predominantly in the lateral direction and successive iterations of stamen primordia are inserted alternately at more or less the same level. In both genera, further expansion in the lateral plane spreads the stamens into a ring around the hypanthium. Agonis flexuosa is similar to Leptospermum. Other variable factors include the timing at which stamen initiation commences (earlier in Leptospermum than Kunzea), the duration of stamen initiation (hence the total number of stamens produced – varies within genera), and very late differential expansion that forces stamens into secondary antesepalous groups in A. flexuosa and L. myrsinoides.The authors thank Dr H. Toelken for kindly providing some material and the impetus for this project. This research was supported by Australian Research Council grant AS19131815. 相似文献
12.
Sarawood Sungkaew Atchara Teerawatananon John A. N. Parnell Chris M. A. Stapleton Trevor R. Hodkinson 《Kew Bulletin》2008,63(4):669-673
Summary A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa. 相似文献
13.
AFLP analysis of genetic relationships among aromatic grapevines (<Emphasis Type="Italic">Vitis vinifera</Emphasis>) 总被引:2,自引:0,他引:2
Fanizza G Chaabane R Lamaj F Ricciardi L Resta P 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(6):1043-1047
Genotypic diversity has been detected among aromatic grapevines (Vitis vinifera) by molecular markers (AFLPs). The 22 primer-pairs generated a total of 1,331 bands of which 564 (40%) were polymorphic over all the genotypes. The bootstrap analysis pointed out that a large number of polymorphic bands (200–400) has to be used for a better estimation of the genetic distances among genotypes; 383 polymorphic AFLP bands were used for the cluster and the principal coordinate analyses because they did not present missing data across all the genotypes. The cluster analysis (UPGMA), based on polymorphic AFLP markers, revealed no relationship between the Moscato and Malvasia grapevines. The Malvasias, unlike the Moscatos distinguished by their distinct muscat aroma, have to be considered a more complex group because it includes muscat and non-muscat grapevines. The principal coordinate analysis (PCO) confirmed the pattern of the cluster analysis only for those varieties which presented a low coefficient of dissimilarity, while for the other varieties there was no correspondence between the two analyses. The pattern of aggregation among aromatic grapevines in the cluster and principal coordinate analyses does not support any classification that might include an aromatic grapevine group in V. vinifera. Even though some synonyms and homonyms are present among aromatic grapevines (V. vinifera), genetic diversity exists among genotypes in AFLP markers.Communicated by H.F. Linskens 相似文献
14.
Genetic variability among 122 Rhynchosporium secalis isolates collected from barley in three regions of Tunisia was investigated using host differentials, amplified fragment
length polymorphism (AFLP), and microsatellite markers. The isolates were collected from a widely grown scald-susceptible
barley cultivar Rihane and a range of local landrace cultivars in geographically distinct regions with different agroclimatic
conditions. Pathotypic diversity (the proportion of unique pathotypes) was high in R. secalis populations from the high (100% diversity), moderate (95%), and low (100%) rainfall areas of Tunisia, and from both Rihane
(which is the sole variety grown in the high rainfall region) and local landraces (which predominate in the low rainfall area).
This may reflect a general adaptability for aggressiveness and suggests that the widely grown cultivar Rihane has exerted
little or no selection pressure on the pathogen population since its release in 1983. Genotypic diversity (GD), defined as
the probability that two individuals taken at random had different genotypes, was high for populations from Rihane, local
landraces, and different agro-ecological zones (GD = 0.96–0.99). There was low genetic differentiation among pathogen populations
from different host populations (G
ST ≤ 0.08, θ ≤ 0.12) and agro-ecological zones (G
ST ≤ 0.05, θ ≤ 0.04), which may be partly explained by gene flow due to the movement of infected stubble around the country.
There was no correlation (r = 0.06, P = 0.39) between virulence phenotype and AFLP haplotype. A phenetic tree revealed groups with low bootstrap values that did
not reflect the grouping of isolates based on host, pathotype, or agro-ecological region. The implications of these findings
for R. secalis evolutionary potential and scald-resistance breeding in Tunisia are discussed. 相似文献
15.
D. J. Goyder 《Kew Bulletin》2008,63(2):331-333
Summary
Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed. 相似文献
16.
Cortinarius subalboviolaceus var. niigatensis var. nov., which grows in deciduous forests, is described and illustrated from Niigata and Gunma prefectures, Japan. It differs
from C. subalboviolaceus var. subalboviolaceus mainly in its more distinct violet coloration and somewhat larger size of the basidiocarp. 相似文献
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19.
ANGUSTIFOLIA (AN), a plant homolog of C-terminal binding protein, controls the polar elongation of leaf cells and the trichome-branching pattern in Arabidopsis thaliana. In the present study, degenerate PCR was used to isolate an ortholog of AN, referred to as LgAN, from larch (Larix gmelinii). The LgAN cDNA is predicted to encode a protein of 646 amino acids that shows striking sequence similarity to AN proteins from other plants. The predicted amino acid sequence has a conserved NAD-dependent 2-hydroxy acid dehydrogenase (D2-HDH) motif and a plant AN-specific LxCxE/D motif at its N-terminus, as well as a plant-specific long C-terminal region. The LgAN gene is a single-copy gene that is expressed in all larch tissues. Expression of the LgAN cDNA rescued the leaf width and trichome-branching pattern defects in the angustifolia-1 (an-1) mutant of Arabidopsis, showing that the LgAN gene has effects complementary to those of AN. These results suggest that the LgAN gene has the same function as the AN gene. 相似文献
20.
Summary A new species of Macroptilium sect. Microcochle (Benth.) J. A. Lackey is herein described from the states of Piauí and Bahia, Brazil. Macroptilium cochleatum is characterized by few-flowered inflorescences, calyx teeth longer than the tube, a tightly four-coiled keel, and linear,
patent fruits. The discovery of this unique Macroptilium species, with its distally coiled keel, expands the diagnostic features of the genus. A key to the Brazilian species of sect.
Microcochle is provided. 相似文献