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1.
Ljubinka Francuski Jasmina Ludoški Ante Vujić Vesna Milankov 《Journal of Insect Conservation》2011,15(3):379-388
Cryptic species and phenotypic divergent units provided useful information about hidden biodiversity in the Merodon genus (Diptera, Syrphidae) on the Balkan Peninsula. Discrimination three cryptic species within both the M. aureus (M. aureus A, M. aureus B and M. aureus C) and M. cinereus (M. cinereus A, M. cinereus B and M. cinereus C) complexes was done by study of subtle wing variation (wing size and shape) using a geometric morphometric approach. Observed
interspecific differentiation is generally in agreement with a previous study using molecular markers (allozyme loci, COI
mtDNA). A considerable evolutionary and phenotypic intraspecies diversity of the M. aureus A, M. aureus B, M. aureus C, M. cinereus A, M. cinereus B, M. cinereus C and M. funestus species from the Balkan Peninsula has important implications for diagnosing biodiversity, including endemic and cryptic species.
Observed phenotypic divergent units within the species might be considered as an evolutionary potential of the M. aureus group and used for defining conservation priorities. This study has contributed to the recognition of the value of wing traits
in order to decipher the hidden diversity and evolutionary diversification. 相似文献
2.
Qiang Fan Sufang Chen Renchao Zhou Xu Xiang Wenbo Liao Suhua Shi 《Conservation Genetics》2011,12(3):753-760
Understanding the amount and distribution of genetic diversity in natural populations can inform the conservation strategy
for the species in question. In this study, genetic variation at eight nuclear microsatellite loci was used to investigate
genetic diversity and population structure of wild litchi (Litchi chinensis Sonn. subsp. chinensis). Totally 215 individuals were sampled, representing nine populations of wild litchi. All eight loci were polymorphic, with
a total of 51 alleles. The expected heterozygosity in the nine populations ranged from 0.367 to 0.638 with an average value
of 0.526. Inbreeding within wild litchi populations was indicated by a strong heterozygote defect. Significant bottleneck
events were detected in the populations from Yunnan and Vietnam, which could be responsible for lower levels of genetic diversity
in these populations. Measures of genetic differentiation (F
ST = 0.269) indicated strong differentiation among wild litchi populations. Significant correlation was found between genetic
differentiation and geographical distance (r = 0.655, P = 0.002), indicating a strong isolation by distance in these populations. Bayesian clustering suggested genetic separation
among three regional groups, namely, the western group, the central group and the eastern group. Some conservation strategies
for wild litchi populations were also proposed based on our results. 相似文献
3.
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
4.
Summary A key is presented to the Nepenthes group Montanae in Peninsular Malaysia, Thailand and Cambodia. Nepenthes bokor Cheek is described from Cambodia and Nepenthes thai Cheek from peninsular Thailand. The affinities of both taxa are discussed and their conservation status assessed. 相似文献
5.
Agbeko Kodjo Tounou Christiann Kooyman Ouro Kobi Douro-Kpindou Hans Michael Poehling 《BioControl》2008,53(5):813-828
Field trials were conducted to evaluate the efficacy of wheat bran bait formulations of Paranosema locustae and Metarhizium anisopliae for controlling grasshoppers in southeast Niger. Treatments consisted of wheat bran baits mixed with M. anisopliae, P. locustae + M. anisopliae or with P. locustae spores and P. locustae + sugar. Oedaleus senegalensis, Pyrgomorpha cognata and Acrotylus blondeli were the predominant species at the time of application representing ca. 94% of the total population. Bran application was
done when O. senegalensis (ca. 75% of the population) was at its early developmental stages, with first, second and third instars accounting for 64–85%.
Grasshopper population reduction, P. locustae prevalence and level of infections in the predominant species were monitored. Manual application of P. locustae and M. anisopliae formulated in wheat bran has proven to induce consistent pathogen infection in grasshopper populations. Population density
over the three weeks monitoring, typically decreased by 44.7 ± 6.9%, 52.8 ± 8.4%, 73.7 ± 5.5% and 89.1 ± 1.8% in P. locustae, P. locustae + sugar, M. anisopliae and P. locustae + M. anisopliae treated plots respectively. Paranosema locustae prevalence in surviving adult grasshoppers at 28 after application was 48.1 ± 2.3%, 28.9 ± 4.8% and 27.4 ± 3.7%, with infection
level of 6.2 ± 0.8 × 106, 2.3 ± 0.3 × 104 and 2.1 ± 0.3 × 103 spores mg−1 host weight in O. senegalensis, A blondeli and P. cognate respectively. Other species that each accounted for <2% of the community, namely Aiolopus thalassinus, A. simulatrix, Acorypha glaucopsis, Acrotylus patruelis, Anacridium melanorhodon, Diabolocatantops axillaris, Kraussaria angulifera and Schistocerca gregaria were found to show sign of infection. The results from this study suggest that wheat bran application of M. anisopliae and P. locustae alone or in combination, targeting early instars grasshopper could be a valuable option in grasshopper control programs. 相似文献
6.
Summary Seven new names at species rank are proposed in Memecylon sect. Afzeliana Jacq.-Fél., a group of forest shrubs and small trees confined to Guineo-Congolian Africa. The group is centred in Cameroon,
where 17 of the 20 species occur. A new flower type, the “star-flower” in Memecylon is revealed, and its taxonomic and ecological importance discussed. Three new, locally endemic species from the South West
Province of Cameroon are described, mapped and illustrated: M. kupeanum R. D. Stone, Ghogue & Cheek, M. bakossiense R. D. Stone, Ghogue & Cheek, and M. rheophyticum R. D. Stone, Ghogue & Cheek. Two new names, M. accedens R. D. Stone, Ghogue & Cheek and M. hyleastrum R. D. Stone & Ghogue and one new combination, M. mamfeanum (Jacq.-Fél.) R. D. Stone, Ghogue & Cheek are provided at species level for three taxa originally proposed as varieties of
M. afzelii G. Don. The taxon M. arcuatomarginatum var. simulans Jacq.-Fél. is also elevated to species status, as M. simulans (Jacq.-Fél.) R. D. Stone & Ghogue. Conservation assessments are provided for all the newly named taxa. A key is provided
to the species of Memecylon sect. Afzeliana. 相似文献
7.
Iain Darbyshire 《Kew Bulletin》2008,63(2):261-268
Summary Three new species are described in Barleria L. sect. Stellatohirta M. Balkwill from tropical Africa: B. aristata from south-central Tanzania, B. aenea from south-western Tanzania and northeast Zambia, and B. purpureotincta from south-western Zambia. Their affinities and conservation status are discussed. 相似文献
8.
Commiphora wightii is a medicinally important endangered species endemic to the Thar Desert of Rajasthan, India and adjoining areas of Pakistan.
The populations of this species are declining sharply because of its extensive use as a natural herb. Random amplified polymorphic
DNA analysis was conducted to find the genetic variation among 7 populations of C. wightii. Of the 100 random primers screened, 44 primers yielded 220 loci. Statistical analysis indicated low genetic diversity (H
pop = 0.0958; I = 0.1498; mean polymorphic loci = 14.28%), and high genetic differentiation among the populations (G
ST = 0.3990; AMOVA Φ
ST of 0.3390; Bayesian θ
(II) = 0.3002). The low genetic diversity may be due to geographic isolation and restricted gene flow (N
m = 0.7533) between the fragmented populations. Unsustainable utilization of the plant has fragmented the population continuum
which served the purpose of genetic exchange between populations. Mantel’s test was performed which revealed a highly significant
positive correlation between genetic and geographic distance (r
2 = 0.614, P = 0.023) among the populations studied. Low variation can also be attributed to poor seed setting and the slow growth pattern
of the species, which is also an apomict. In UPGMA dendrogram the Commiphora wightii samples were divided into two major and one minor cluster. These findings can serve as a guide to preserving the genetic
resources of this medicinal plant species. 相似文献
9.
Nina Yasuda Satoshi Nagai Chunlian Lian Masami Hamaguchi Takeshi Hayashibara Kazuo Nadaoka 《Conservation Genetics》2008,9(4):1011-1013
We isolated 11 polymorphic microsatellites from blue coral (Heliopora coerulea), whose conservation and management are of great concern. The number of alleles ranged from 3 to 20 with an average of 5.5,
and the observed and expected heterozygosities ranged from 0.115 to 0.833 and from 0.371 to 0.915, respectively. These loci
are useful for conservation genetics in H. coerulea populations. 相似文献
10.
Berchemiella wilsonii var. pubipetiolata (Rhamnaceae) is an endangered tree in eastern China. Habitat destruction has resulted in fragmentation of remnant populations
and extinction of local populations. AFLP and cpDNA markers were used to determine the population structure of remnant populations
of B. wilsonii var. pubipetiolata. Moderate nuclear genomic diversity was found within each of the four remnant populations (H
S = 0.141–0.172), while the cpDNA haplotype diversity in each population ranged from 0.356 to 0.681. Six haplotypes were identified
by a combined cpRFLP and cpSSR analysis in a total of 89 individuals. AMOVA revealed significantly AFLP genetic differentiation
within and between regions (ΦSC = 0.196, ΦCT = 0.396, respectively), and a high cpDNA haplotype differentiation between regions (ΦCT = 0.849). The results suggest low gene flow between populations of B. wilsonii var. pubipetiolata. Strong genetic divergence between two regional populations as revealed by both AFLP and cpDNA markers provided convincing
evidence that two distinct evolutionary lineages existed, and should be recognized as ‘evolutionary significant units’ (ESUs)
for conservation concerns. 相似文献
11.
We investigated the degree and distribution of the genetic variation, and phylogeography, of two species of Malagasy poison
frogs, Mantella cowani and M. baroni. The former is critically endangered due to its restricted distribution, habitat destruction and overcollection for the pet
trade. Analysis of 526 bp of mtDNA (cytochrome b) resulted in separate haplotype networks for the two species, and discovered hybridization at a single locality. The two
networks confirm the status of M. baroni and M. cowani as separate evolutionary species and units for conservation. Within both mitochondrial haplotype networks, specimens from
different localities shared numerous identical haplotypes, even those from the most distant sample sites of M. baroni. Most populations were characterized by high haplotype diversity and no haplotype clades exclusive to geographical regions
were observed. Protection of a few large populations of these species is therefore likely to conserve much of the mtDNA genetic
diversity found in the entire species. While M. baroni is widespread and occurs in many nature reserves, we recommend efficient legal protection of some M. cowani habitats to protect this species against extinction. 相似文献
12.
A genetic transformation protocol for green ash (Fraxinus pennsylvanica) hypocotyl explants was developed. Green ash hypocotyls were transformed using Agrobacterium tumefaciens strain EHA105 harboring binary vector pq35GR containing the neomycin phosphotransferase (nptII) and β-glucuronidase (GUS) fusion gene, and an enhanced green fluorescent protein gene. Pre-cultured hypocotyl explants were
transformed in the presence of 100 μM acetosyringone using 90 s sonication plus 10 min vacuum-infiltration. Kanamycin at 20 mg l−1 was used for selecting transformed cells. Adventitious shoots regenerated on Murashige and Skoog medium supplemented with
13.3 μM 6-benzylaminopurine, 4.5 μM thidiazuron, 50 mg l−1 adenine sulfate, and 10% coconut water. GUS- and polymerase chain reaction (PCR)-positive shoots from the cut ends of hypocotyls
were produced via an intermediate callus stage. Presence of the GUS and nptII genes in GUS-positive shoots were confirmed by PCR and copy number of the nptII gene in PCR-positive shoots was determined by Southern blotting. Three transgenic plantlets were acclimatized to the greenhouse.
This transformation and regeneration system using hypocotyls provides a foundation for Agrobacterium-mediated transformation of green ash. Studies are underway using a construct containing the Cry8Da protein of Bacillus thuringiensis for genetic transformation of green ash. 相似文献
13.
Summary The first occurrence of the genus Metarungia Baden (Acanthaceae) in west Africa is recorded with the discovery of an isolated population of the widespread eastern African taxon M. pubinervia (T. Anderson) Baden in eastern Nigeria. The conservation status of this species is discussed. 相似文献
14.
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
15.
Subspecific taxa of species complexes can display cryptic morphological variation, and individuals and populations can often
be difficult to identify with certainty. However, accurate population identification is required for comprehensive conservation
and breeding strategies and for studies of invasiveness and gene flow. Using five informative microsatellite markers and a
Bayesian statistical approach, we developed an efficient polymerase chain reaction-based diagnostic tool for the rapid identification
of individuals and populations of the Acacia saligna species complex of Western Australia. We genotyped 189 individuals from 14 reference populations previously characterised
based on morphology and used these data to investigate population structure in the species complex. High total genetic diversity
(H
T = 0.729) and high population differentiation (θ = 0.355) indicated strong intraspecific structuring. With the provision of prior population information, the reference data
set was optimally resolved into four clusters, each corresponding to one of the four main proposed subspecies, with very high
membership values (Q > 97%). The reference data set was then used to assign individuals and test populations to one of the four subspecies. Assignment
was unequivocal for all test individuals from two populations of subsp. lindleyi and for all but one individual of subsp. stolonifera. Individuals from populations of subsp. saligna and subsp. pruinescens showed a degree of genetic affinity for the two subspecies in their assignments, although the majority of individuals were
correctly assigned to subspecies. The diagnostic tool will assist in characterising populations of A. saligna, especially naturalised and invasive populations of unknown origin. 相似文献
16.
Samantha M. Wisely Rachel M. Santymire Travis M. Livieri Sara A. Mueting JoGayle Howard 《Conservation Genetics》2008,9(2):389-399
Population augmentation with translocated individuals has been shown to alleviate the effects of bottlenecks and drift. The
first step to determine whether restoration for genetic considerations is warranted is to genetically monitor reintroduced
populations and compare results to those from the source. To assess the need for genetic restoration, we evaluated genetic
diversity and structure of reintroduced (n = 3) and captive populations of the endangered black-footed ferret (Mustela nigripes). We measured genotypic changes among populations using seven microsatellite markers and compared phenotypic changes with
eight morphometric characters. Results indicated that for the population which rapidly grew post-reintroduction, genetic diversity
was equivalent to the captive, source population. When growth languished, only the population that was augmented yearly maintained
diversity. Without augmentation, allelic diversity declined precipitously and phenotypic changes were apparent. Ferrets from
the genetically depaupertate population had smaller limbs and smaller overall body size than ferrets from the two populations
with greater diversity. Population divergence (F
ST = 0.10 ± 0.01) was surprisingly high given the common source of populations. Thus, it appears that 5–10 years of isolation
resulted in both genotypic divergence and phenotypic changes to populations. We recommend translocation of 30–40 captive individuals
per annum to reintroduction sites which have not become established quickly. This approach will maximize the retention of
genetic diversity, yet maintain the beneficial effects of local adaptation without being swamped by immigration. 相似文献
17.
The Oregon spotted frog (Rana pretiosa) is one of the most threatened amphibians in the Pacific Northwest. Here we analyzed data from 13 microsatellite loci and
298 bp of mitochondrial DNA in frogs collected from 23 of the remaining R. pretiosa populations in order to (1) assess levels of genetic diversity within populations of R. pretiosa, (2) identify the major genetic groups in the species, (3) estimate levels of genetic differentiation and gene flow among
populations within each major group, and (4) compare the pattern of differentiation among R. pretiosa populations with that among populations of R. cascadae, a non-endangered congener that also occurs in Oregon and Washington. There is a strong, hierarchical genetic structure in
R. pretiosa. That structure includes six major genetic groups, one of which is represented by a single remaining population. R. pretiosa populations have low genetic diversity (average H
e = 0.31) compared to R. cascadae (average H
e = 0.54) and to other ranid frogs. Genetic subdivision among populations is much higher in R. pretiosa than in R. cascadae, particularly over the largest geographic distances (hundreds of kilometers). A joint analysis of migration rates among populations
and of effective sizes within populations (using MIGRATE) suggests that both species have extremely low migration rates, and
that R. pretiosa have slightly smaller effective sizes. However, the slight difference in effective sizes between species appears insufficient
to explain the large difference in genetic diversity and in large-scale genetic structure. We therefore hypothesize that low
connectivity among the more widely-spaced R. pretiosa populations (owing to their patchier habitat), is the main cause of their lower genetic diversity and higher among-population
differentiation. Conservation recommendations for R. pretiosa include maintaining habitat connectivity to facilitate gene flow among populations that are still potentially connected,
and either expanding habitat or founding additional ‘backup’ populations to maintain diversity in the isolated populations.
We recommend that special consideration be given to conservation of the Camas Prairie population in Northern Oregon. It is
the most geographically isolated population, has the lowest genetic diversity (H
e = 0.14) and appears to be the only remaining representative of a major genetic group that is now almost extinct. Finally,
because the six major groups within R. pretiosa are strongly differentiated, occupy different habitat types, and are geographically separate, they should be recognized as
evolutionarily significant units for purposes of conservation planning. 相似文献
18.
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
19.
The analysis of 135 mitochondrial D-loop sequences of the Iberian autochthonous red-legged partridge (Alectoris rufa) from wild population hunting bags from various locations and fowl runs in Spain yielded 37 different haplotypes. Among these,
three haplotypes correspond to chukar partridges (Alectoris chukar), indicating genetic introgression from birds illegally introduced for restocking: three individuals carrying such haplotypes
where found in natural populations, one appeared among those sampled on a mass reproduction farm and the remaining 10 in another
fowl-run. The geographical origin of the contaminating chukar haplotypes could be assigned to the most easterly area of the
chukar partridge geographical distribution in China. Molecular diversity parameters in the A. rufa samples indicate a considerable amount of genetic variation. ΦST showed significant differences among populations that are not explained by geographical distance alone. Particularly, one
northern population (Palencia) shows a certain degree of genetic differentiation that could reflect a previously suggested
subspecies division.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
20.
Yessica Rico Consuelo Lorenzo Francisco X. González-Cózatl Eduardo Espinoza 《Conservation Genetics》2008,9(6):1467-1477
The Tehuantepec jackrabbit (Lepus flavigularis) is an endangered species restricted to a small area in the Isthmus of Tehuantepec, Oaxaca, Mexico. To evaluate its phylogeographic
structure, population genetics, and demographic history we sequenced the mitochondrial Control Region hypervariable domain
(CR-1) for 42 individuals representing the entire species range. Phylogenetic patterns indicated that this species is subdivided
into two highly divergent clades, with an average nucleotide genetic distance of 3.7% (TrN) between them. Clades A and B are
geographically distributed in non-overlapping areas to the west and to the east of the Isthmus of Tehuantepec, respectively.
Genetic diversity indices showed reduced genetic variability in L. flavigularis when compared to other species of Lepus within main clades and within populations. This low genetic diversity coupled with the restricted distribution to very small
areas of occurrence and limited gene flow suggest that genetic drift has played an important role in the evolution of this
species. Historical demographic analysis also pointed out that these two clades underwent a recent population expansion that
started about 9,000 years ago for clade A and 3,200 years ago for clade B during the Holocene. Consequently, from the conservation
perspective our results suggest that populations included in clades A and B should be regarded as distinct evolutionary lineages. 相似文献