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1.
J. C. Hunter 《Trees - Structure and Function》1997,11(3):169-175
For the angiosperm dominants of northern California’s mixed evergreen forests, this study compares the display of photosynthetic
tissue within leaves and along branches, and examines the correspondence between these morphological attributes and the known
environmental tolerances of these species. Measurements were made on both sun and shade saplings of six species: Arbutus
m
e
n
z
i
e
s
i
i (Ericaceae), C
h
r
y
s
o
l
e
p
i
s
c
h
r
y
s
o
p
h
y
l
l
a (Fagaceae), L
i
t
h
o
c
a
r
p
u
s
d
e
n
s
i
f
l
o
r
u
s (Fagaceae), Quercus
c
h
r
y
s
o
l
e
p
i
s (Fagaceae), Quercus
w
i
s
l
i
z
e
n
i
i (Fagaceae), and Umbellularia
c
a
l
i
f
o
r
n
i
c
a (Lauraceae). All species had sclerophyllous leaves with thick epidermal walls, but species differed in leaf specific weight,
thickness of mesophyll tissues and in the presence of a hypodermis, crystals, secretory idioblasts, epicuticular deposits,
and trichomes. The leaves of Arbutus were 2 – 5 times larger than those of C
h
r
y
s
o
l
e
p
i
s, L
i
t
h
o
c
a
r
p
u
s and Umbellularia and 4 – 10 times larger than those of both Quercus species. Together with differences in branch architecture, these leaf traits divide the species into groups corresponding
to environmental tolerances. Shade-tolerant C
h
r
y
s
o
l
e
p
i
s, L
i
t
h
o
c
a
r
p
u
s, and Umbellularia had longer leaf lifespans and less palisade tissue, leaf area, and crown mass per volume than the intermediate to intolerant
Arbutus and Quercus. Having smaller leaves, Quercus branches had more branch mass per leaf area and per palisade volume than other species, whereas Arbutus had less than other species. These differences in display of photosynthetic tissue should contribute to greater growth for
Quercus relative to the other species under high light and limited water, for Arbutus under high light and water availability, and for C
h
r
y
s
o
l
e
p
i
s, L
i
t
h
o
c
a
r
p
u
s, and Umbellularia under limiting light levels.
Accepted: 22 March 1996 相似文献
2.
Kwang‐Su Lee Tae Hwa Kang Ji Woong Jeong Dong Pyo Ryu Heung‐Sik Lee 《Entomological Research》2015,45(5):225-234
A taxonomic review of the Korean Lymantria Hübner, 1819 was conducted. A total of nine species of five subgenera with two unrecorded species are listed: Lymantria (Porthetria) dispar Linnaeus 1758, L. (P.) xylina Swinhoe 1903, L. (Lymantria) monacha (Linnaeus 1758), L. (L.) minomonis Matsumura 1933 (new to Korea), L. (L.) similis monachoides Schintlimeister 2004 (new to Korea), L. (L.) lucescens (Butler 1881), L. (Nyctria) mathura Moore 1865, L. (Collentria) fumida Butler 1877, and L. (Spinotria) bantaizana Matsumura 1933. Lymantria (Lymantria) minomonis and L. (L.) similis monachoides are newly added to the Korean fauna. Lymantria (L.) minomonis was found only on Bogildo Island of Jeollanam‐do in the southern part of Korea, and L. (L.) similis monachoides was collected in central Korea. Lymantria (Porthetria) xylina and L. (Collentria) fumida were not examined in this study, and it is considered that the previous records were due to misidentification or they are only distributed in the northern part of the Korean Peninsula. We provide diagnoses of two unrecorded species and adult habitus and genitalia photos of the Korean Lymantria species. 相似文献
3.
CHRISTOPHE DAUGERON PATRICK GROOTAERT 《Zoological Journal of the Linnean Society》2005,145(3):339-391
Six clades are inferred from a phylogenetic analysis including 42 species belonging to the Empis (Coptophlebia) hyalea‐group. These clades are named as follows: E. (C.) acris, E. (C.) aspina, E. (C.) atratata, E. (C.) hyalea, E. (C.) jacobsoni and E. (C.) nahaeoensis. The presence of two dorsal more or less developed epandrial projections is considered autapomorphic for the E. (C.) hyalea‐group in addition to two characters previously found to support the monophyly of this group (presence of an unsclerotized zone in the middle of labella and epandrium unpaired). Amongst the cladistically analysed species, 24 are newly described [ E. ( C. ) acris , E. ( C. ) aspina , E. ( C. ) cameronensis , E. ( C. ) duplex , E. ( C. ) incurva , E. ( C. ) inferiseta , E. ( C. ) kuaensis , E. ( C. ) lachaisei , E. ( C. ) lamellalta , E. ( C. ) lata , E. ( C. ) loici , E. ( C. ) longiseta , E. ( C. ) mengyangensis , E. ( C. ) menglunensis , E. ( C. ) missai , E. ( C. ) nimbaensis , E. ( C. ) padangensis , E. ( C. ) parvula , E. ( C. ) projecta , E. ( C. ) pseudonahaeoensis , E. ( C. ) submetallica , E. ( C. ) urumae , E. ( C. ) vitisalutatoris and E. ( C. ) woitapensis ], five are reviewed [E. (C.) hyalea Melander, E. (C.) jacobsoni De Meijere, E. (C.) ostentator Melander, E. (C.) sinensis Melander and E. (C.) thiasotes Melander] and 13 were recently described in two previous papers. Two additional species, E. (C.) abbrevinervis De Meijere and E. (C.) multipennata Melander, are also reviewed but not included in the cladistic analysis since they are only known from the female. A lectotype is designated for E. (C.) jacobsoni. A key is provided to the six clades of the E. (C.) hyalea‐group as well as to species of each clade. A catalogue of the E. (C.) hyalea‐group, including 72 species, is given. The taxonomic status of 25 additional species mainly described by Bezzi and Brunetti, from the Oriental and Australasian regions, is discussed. The E. (C.) hyalea‐group is firstly recorded from the Palaearctic Region and Australia. Finally, the distribution and the habitats of the species compared with their phylogeny suggest a possible relationship between the diversification of the group and forest fragmentations during the Quaternary. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 145 , 339–391. 相似文献
4.
Food attraction of the fungivorous nematodes Aphelenchus avenae and Aphelenchoides spp. to seven fungal species (Pyrenochaeta lycopersici, Botrytis cinerea, Rhizoctonia solani strains AG 3 and AG 2‐1, Verticillium dahliae, Pochonia bulbillosa, Mortierella hyalina and Trichoderma harzianum) was determined on agar plates by counting the number of test nematodes present on the mycelium of each fungus 24 h after inoculation. Population growth of A. avenae and Aphelenchoides spp. on five of the seven fungi included in the attraction test (P. lycopersici, R. solani strain AG 3, V. dahliae, P. bulbillosa and T. harzianum) was also determined on agar plates by counting nematode numbers every week during a 6‐week period. A. avenae and Aphelenchoides spp. were attracted to all the fungi tested. A. avenae was preferentially attracted to V. dahliae (P < 0.0001), and Aphelenchoides spp. did not show any preference except for low attraction to R. solani. A. avenae and Aphelenchoides spp. reproduced on all fungal species tested. After 6 weeks of incubation, the highest number of nematodes was found on P. lycopersici and P. bulbillosa, while the lowest number occurred on R. solani for A. avenae and on T. harzianum for Aphelenchoides spp. The suitability of a fungus as a host was not clearly related to the attraction to that fungus. 相似文献
5.
Fujii T Tanaka N Yokoyama T Ninaki O Oshiki T Ohnuma A Tazima Y Banno Y Ajimura M Mita K Seki M Ohbayashi F Shimada T Abe H 《Genetica》2006,127(1-3):253-265
Bombyx mori is a female-heterogametic organism (female, ZW; male, ZZ) that appears to have a putative feminizing gene (Fem) on the W chromosome. The paternally transmitted mutant W chromosome, Df(p
Sa
+
p
W +
od
)Fem, derived from the translocation-carrying W chromosome (p
Sa
+
p
W +
od
), is inert as femaleness determinant. Moreover, this Df(p
Sa
+
p
W +
od
)Fem chromosome has been thought to have a female-killing factor because no female larvae having the Df(p
Sa
+
p
W +
od
)Fem chromosome are produced. Initially, to investigate whether the Df(p
Sa
+
p
W +
od
)Fem chromosome contains any region of the W chromosome or not, we analyzed the presence or absence of 12 W-specific RAPD markers.
The Df(p
Sa
+
p
W +
od
)Fem chromosome contained 3 of 12 W-specific RAPD markers. These results strongly indicate that the Df(p
Sa
+
p
W +
od
)Fem chromosome contains the region of the W chromosome. Moreover, by using phenotypic and molecular markers, we confirmed that
the Df(p
Sa
+
p
W +
od
)Fem chromosome is connected with a partially deleted Z chromosome and that this fused chromosome behaves as a Z chromosome during
male meiosis. Furthermore, we demonstrated that the ZZW-type triploid female having the Df(p
Sa
+
p
W +
od
)Fem chromosome is viable. Therefore, we concluded that the Df(p
Sa
+
p
W +
od
)Fem chromosome does not have a female-killing factor but that partial deletion of the Z chromosome causes the death of the ZW-type
diploid female having the Df(p
Sa
+
p
W +
od
)Fem chromosome. Additionally, our results of detailed genetic analyses strongly indicate that the female-killing chromosome composed
of the Df(p
Sa
+
p
W +
od
)Fem chromosome and deleted Z chromosome was generated by translocation between the Z chromosome and the translocation-carrying
W chromosome, p
Sa
+
p
W +
od
. 相似文献
6.
7.
Phylogeny and classification of Aedini (Diptera: Culicidae), based on morphological characters of all life stages 总被引:5,自引:0,他引:5
JOHN F. REINERT RALPH E. HARBACH IAN J. KITCHING 《Zoological Journal of the Linnean Society》2004,142(3):289-368
Higher‐level relationships within Aedini, the largest tribe of Culicidae, are explored using morphological characters of eggs, fourth‐instar larvae, pupae, and adult females and males. In total, 172 characters were examined for 119 exemplar species representing the existing 12 genera and 56 subgenera recognized within the tribe. The data for immature and adult stages were analysed separately and in combination using equal (EW) and implied weighting (IW). Since the classification of Aedini is based mainly on adult morphology, we first tested whether adult data alone would support the existing classification. Overall, the results of these analyses did not reflect the generic classification of the tribe. The tribe as a whole was portrayed as a polyphyletic assemblage of Aedes and Ochlerotatus within which eight (EW) or seven (IW) other genera were embedded. Strict consensus trees (SCTs) derived from analyses of the immature stages data were almost completely unresolved. Combining the adult and immature stages data resulted in fewer most parsimonious cladograms (MPCs) and a more resolved SCT than was found when either of the two data subsets was analysed separately. However, the recovered relationships were still unsatisfactory. Except for the additional recovery of Armigeres as a monophyletic genus, the groups recovered in the EW analysis of the combined data were those found in the EW analysis of adult data. The IW analysis of the total data yielded eight MPCs consisting of three sets of two mutually exclusive topologies that occurred in all possible combinations. We carefully studied the different hypotheses of character transformation responsible for each of the alternative patterns of relationship but were unable to select one of the eight MPCs as a preferred cladogram. Overall, the relationships within the SCT of the eight MPCs were a significant improvement over those found by equal weighting. Aedini and all existing genera except Ochlerotatus and Aedes were recovered as monophyletic. Ochlerotatus formed a polyphyletic assemblage basal to Aedes. This group included Haemagogus and Psorophora, and also Opifex in a sister‐group relationship with Oc. (Not.) chathamicus. Aedes was polyphyletic relative to seven other genera, Armigeres, Ayurakitia, Eretmapodites, Heizmannia, Udaya, Verrallina and Zeugnomyia. With the exception of Ae. (Aedimorphus), Oc. (Finlaya), Oc. (Ochlerotatus) and Oc. (Protomacleaya), all subgenera with two or more species included in the analysis were recovered as monophyletic. Rather than leave the generic classification of Aedini in its current chaotic state, we decided a reasonable and conservative compromise classification would be to recognize as genera those groups that are ‘weighting independent’, i.e. those that are common to the results of both the EW and IW analyses of the total data. The SCT of these combined analyses resulted in a topology of 29 clades, each comprising between two and nine taxa, and 30 taxa (including Mansonia) in an unresolved basal polytomy. In addition to ten genera (Armigeres, Ayurakitia, Eretmapodites, Haemagogus, Heizmannia, Opifex, Psorophora, Udaya, Verrallina and Zeugnomyia), generic status is proposed for the following: (i) 32 existing subgenera of Aedes and Ochlerotatus, including nine monobasic subgenera within the basal polytomy, i.e. Ae. (Belkinius), Ae. (Fredwardsius), Ae. (Indusius), Ae. (Isoaedes), Ae. (Leptosomatomyia), Oc. (Abraedes), Oc. (Aztecaedes), Oc. (Gymnometopa) and Oc. (Kompia); (ii) three small subgenera within the basal polytomy that are undoubtedly monophyletic, i.e. Ae. (Huaedes), Ae. (Skusea) and Oc. (Levua), and (iii) another 20 subgenera that fall within the resolved part of the SCT, i.e. Ae. (Aedes), Ae. (Alanstonea), Ae. (Albuginosus), Ae. (Bothaella), Ae. (Christophersiomyia), Ae. (Diceromyia), Ae. (Edwardsaedes), Ae. (Lorrainea), Ae. (Neomelaniconion), Ae. (Paraedes), Ae. (Pseudarmigeres), Ae. (Scutomyia), Ae. (Stegomyia), Oc. (Geoskusea), Oc. (Halaedes), Oc. (Howardina), Oc. (Kenknightia), Oc. (Mucidus), Oc. (Rhinoskusea) and Oc. (Zavortinkius). A clade consisting of Oc. (Fin.) kochi, Oc. (Fin.) poicilius and relatives is raised to generic rank as Finlaya, and Downsiomyia Vargas is reinstated from synonymy with Finlaya as the generic name for the clade comprising Oc. (Fin.) leonis, Oc. (Fin.) niveus and their relatives. Three other species of Finlaya?Oc. (Fin.) chrysolineatus, Oc. (Fin.) geniculatus and Oc. (Fin.) macfarlanei? fall within the basal polytomy and are treated as Oc. (Finlaya) incertae sedis. Ochlerotatus (Ochlerotatus) is divided into three lineages, two of which, Oc. (Och.) atropalpus and Oc. (Och.) muelleri, are part of the basal polytomy. The remaining seven taxa of Oc. (Ochlerotatus) analysed, including the type species, form a reasonably well‐supported group that is regarded as Ochlerotatus s.s. Ochlerotatus (Rusticoidus) is retained as a subgenus within Ochlerotatus s.s. Ochlerotatus (Nothoskusea) is recognized as a subgenus of Opifex based on two unique features that support their sister‐group relationship. A new genus, Tanakaius gen. nov. , is proposed for Oc. (Fin.) togoi and the related species Oc. (Fin.) savoryi. The taxonomic status and generic placement of all currently valid species of Aedini are listed in an appendix. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 142 , 289?368. 相似文献
8.
Russell Taylor 《Biodiversity and Conservation》2009,18(10):2563-2583
Communal Areas Management Programme for Indigenous Resources (CAMPFIRE) is a long-term programmatic approach to rural development
that uses wildlife and other natural resources as a mechanism for promoting devolved rural institutions and improved governance
and livelihoods. The cornerstone of CAMPFIRE is the right to manage, use, dispose of, and benefit from these resources. Between
1989 and 2006, CAMPFIRE income, mostly from high valued safari hunting, totalled nearly USD
30 million, of which 52 allocated to sub-district wards and villages for community projects and household benefits. Whilst a number of assumptions underlying the success of CAMPFIRE as an innovative model for CBNRM have yet to be met, CAMPFIRE confirms the concept that devolving responsibility and accountability for natural resource management can be highly effective for the collective and participatory management of such resources. Elephant numbers in CAMPFIRE areas have increased and buffalo numbers are either stable or decreased slightly during the life of the programme. However, offtake quotas for these two species have increased with a concomitant decline in trophy quality. Although the amount of wildlife habitat diminished after 1980, following the commencement of CAMPFIRE the rate of habitat loss slowed down and in some specific instances was even reversed. More recently there has been increased pressure on habitats and other natural resources as a consequence of deterioraa
30 million, of which 52% was
allocated to sub-district wards and villages for community projects and household benefits. Whilst a number of assumptions
underlying the success of CAMPFIRE as an innovative model for CBNRM have yet to be met, CAMPFIRE confirms the concept that
devolving responsibility and accountability for natural resource management can be highly effective for the collective and
participatory management of such resources. Elephant numbers in CAMPFIRE areas have increased and buffalo numbers are either
stable or decreased slightly during the life of the programme. However, offtake quotas for these two species have increased
with a concomitant decline in trophy quality. Although the amount of wildlife habitat diminished after 1980, following the
commencement of CAMPFIRE the rate of habitat loss slowed down and in some specific instances was even reversed. More recently
there has been increased pressure on habitats and other natural resources as a consequence of deteriorating socio-economic
conditions in the country. Where devolution has been successful, promising results have been achieved and the recent acceptance
and implementation of direct payments to communities is probably the most significant development since 2000. That this has
happened can be attributed to CAMPFIRE enabling communities to maximize their roles within the existing set of rules, and
by so doing, allowing these rules to be challenged. Donor (73%) and government (27%) investments into the programme amounted
to 35 million during the period 1989 to 2003. Since 2003 however, donor funding has been reduced to <$600,000 over the past
5 years. 相似文献
9.
Ortega E Bosković RI Sargent DJ Tobutt KR 《Molecular genetics and genomics : MGG》2006,276(5):413-426
Cross-compatibility relationships in almond are controlled by a gametophytically expressed incompatibility system partly mediated by stylar RNases, of which 29 have been reported. To resolve possible synonyms and to provide data for phylogenetic analysis, 21 almond S-RNase alleles were cloned and sequenced from SP (signal peptide region) or C1 (first conserved region) to C5, except for the S
29
allele, which could be cloned only from SP to C1. Nineteen sequences (S
4
, S
6
, S
11
–S
22
, S
25
–S
29
) were potentially new whereas S
10
and S
24
had previously been published but with different labels. The sequences for S
16
and S
17
were identical to that for S
1
, published previously; likewise, S
15
was identical to S
5
. In addition, S
4
and S
20
were identical, as were S
13
and S
19
. A revised version of the standard table of almond incompatibility genotypes is presented. Several alleles had AT or GA tandem repeats in their introns. Sequences of the 23 distinct newly cloned or already published alleles were aligned. Sliding windows analysis of Ka/Ks identified regions where positive selection may operate; in contrast to the Maloideae, most of the region from the beginning of C3 to the beginning of RC4 appeared not to be under positive selection. Phylogenetic analysis indicated four pairs of alleles had ‘bootstrap’ support > 80%: S
5
/S
10
, S
4
/S
8,
S
11
/S
24
, and S
3
/S
6
. Various motifs up to 19 residues long occurred in at least two alleles, and their distributions were consistent with intragenic recombination, as were separate phylogenetic analyses of the 5′ and 3′ sections. Sequence comparison of phylogenetically related alleles indicated the significance of the region between RC4 and C5 in defining specificity.An erratum to this article can be found at 相似文献
10.
Genetics of tolerance to iron chlorosis was investigated in eight crosses involving parents distinctly different in their level of tolerance. The segregating populations with parents and F1s were screened under actual stress conditions in the field. Also, selected crosses were studied for Fe3+ uptake capacity. Tolerance/moderate tolerance to Fe chlorosis was dominant over susceptibility and it was controlled by two sets of nonallelic genes with complementary interaction. Gene Ic
1 has been found to be basic and in complementation with Ic
3 it confers tolerance. Likewise, Ic
2 with Ic
4 confers tolerance. The basic genes Ic
1 and Ic
2 are nonallelic and, in the absence of their respective complementary genes Ic
3
and
4
, ineffective, which results in susceptibility. Of tolerant cultivars, ARC 10372 and Cauvery have been tentatively assigned the genotype of Ic
1
, Ic
2
, Ic
3
, Ic
4
, and moderately tolerant IET 7613, Prasanna and Akashi Ic
1
,
2
Ic
3
Ic
4
. The susceptible ARC 5723 has been assigned Ic
1
,
2
, Ic
3
, Ic
4
, and IET 9829, Ic
1
,
2
Ic
3
Ic
4
. IET 7614 is susceptible, due to the presence of inhibitory genes I-Ic
1
, I-Ic
2
together with ic
1
pt>, ic
2
, Ic
3
, Ic
4
. Further, the gene Pc for purple coleoptile shows linkage with one of the complementary genes with a crossover value of 15.26%, while the gene(s) for seedling height Ts with Ic
1 with a crossover value of 1.7%. It is possible that the gene(s) for iron chlorosis tolerance might belong to the second linkage group, where genes for purple leaf were located. 相似文献
11.
We previously identified both self-incompatible and self-compatible plants in a natural population of self-incompatible Petunia axillaris subsp. axillaris, and found that all the self-compatible plants studied carried either SC1- or SC2-haplotype. Genetic crosses showed that SC2 was identical to S17 identified from another natural population of P. axillaris, except that its pollen function was defective, and that the pollen-part mutation in SC2 was tightly linked to the S-locus. Recent identification of the S-locus F-box gene (SLF) as the gene that controls pollen specificity in S-RNase-based self-incompatibility has prompted us to examine the molecular basis of this pollen-part mutation. We cloned and sequenced the S17-allele of SLF of P.axillaris, named PaSLF17, and found that SC2 SC2 plants contained extra restriction fragments that hybridized to PaSLF17 in addition to all of those observed in S17 S17 plants. Moreover, these additional fragments co-segregated with SC2. We used the SC2-specific restriction fragments as templates to clone an allele of PaSLF by PCR. To determine the identity of this allele, named PaSLFx, primers based on its sequence were used to amplify PaSLFalleles from genomic DNA of 40 S-homozygotes of P. axillaris, S1 S1 through S40 S40. Sequence comparison revealed that PaSLFx was completely identical with PaSLF19 obtained from S19 S19. We conclude that the S-locus of SC2 contained both S17-allele and the duplicated S19-allele of PaSLF. SC2 is the first naturally occurring pollen-part mutation of a solanaceous species that was shown to be associated with duplication of the pollen S. This finding lends support to the proposal, based on studies of irradiation-generated pollen-part mutants of solanaceous species, that duplication, but not deletion, of the pollen S, causes breakdown of pollen function. 相似文献
12.
Aims: To evaluate the frequency of the aerolysin (aerA), cytotoxic enterotoxin (alt) and serine protease (ahp) genes in Aeromonas hydrophila isolates from different sources, and to determine the relationship between the presence of these genes and virulence of A. hydrophila in zebrafish. Methods and Results: Aeromonas hydrophila isolates from clinical cases (n = 40), from healthy fish (n = 22) and from water environment (n = 21) were analysed with respect to the prevalence of aerA, alt and ahp genes by PCR assay. These virulence factors occur among clinical isolates as well as among isolates from healthy fish and water environment. The majority (97·6%) of the strains examined carried one or more virulence genes. The isolates were divided into seven genetic profiles on the basis of PCR result: aerA+alt+ahp+ (62·7%), aerA+alt+ahp? (13·3%), aerA+alt?ahp+ (10·8%), aerA?alt+ahp+ (4·8%), aerA?alt?ahp+ (3·6%), aerA+alt?ahp? (2·4%) and aerA?alt?ahp? (2·4%). A higher frequency of genetic group aerA+alt+ahp+ was determined in the isolates from diseased animals compared to those from healthy fish or water environments. Virulence properties of 26 representative strains belonging to the seven genetic profiles were further characterized. Results demonstrated that as the present of virulence genes increased, the proteolytic, haemolytic and cytotoxic activities of extracellular products also increased. And the 50% lethal doses (LD50s) of aerA+alt+ahp+ isolates (<105) in zebrafish were lower when compared with the strains expressing one or combinations of two virulence genes (>106). Conclusions: Virulence properties of A. hydrophila correlated well with the presence of virulence genes tested. aerA+alt+ahp+ was more frequent virulence genotype in A. hydrophila isolates from clinical diseases than from healthy fish and water environment, and the aerA+alt+ahp+ isolates were more virulent to zebrafish compared to the other six genetic profiles. Significant and Impact of the Study: The detection for aerA, alt and ahp can be used for virulence typing of A. hydrophila isolates. 相似文献
13.
14.
A self-compatible mutant S allele conferring a dominant negative effect on the functional S allele in Ipomoea trifida 总被引:2,自引:0,他引:2
A spontaneously occurring self-compatible mutant has been identified in Ipomoea trifida, a species possessing sporophytic self-incompatibility controlled by a single multiallelic S locus. Analysis of the segregation of compatibility/incompatibility phenotypes in selfed and crossed progenies of the self-compatible
mutant plant indicated that the self-compatibility trait was caused by a mutation at the S locus; the mutated S allele was therefore designated Sc. RFLP analysis of progeny plants segregating for the Sc allele using the SSP gene (a gene linked closely to the S locus of I. trifida) as a probe confirmed that the mutation was present at the S locus. Self-incompatibility responses were examined in F1 progenies obtained from crosses between the self-compatible mutant and self-incompatible plants homozygous for one of three
S alleles, S
1
, S
3
and S
22
, where the dominance relationship is S
22
>S
1
>S
3
. All F1 progeny plants from crosses with S
22
and S
1
homozygotes were self-incompatible and exhibited the respective phenotypes of each self-incompatible parent (either S
22
or S
1
) in both stigma and pollen. However, of the F1 progeny plants from the cross with the S
3
homozygote, those carrying the genotype ScS
3
were all self-compatible and cross-compatible as both female and male parents with the S
3
homozygote. These results indicate that the dominance relationship between the four S alleles is: S
22
>S
1
>Sc>S
3
and so reveal the unexpected finding that the mutated Sc allele is dominant over a functional S
3
allele. A possible explanation for this observation is that the gene product encoded by the Sc allele confers a dominant negative effect on the S
3
gene product.
Received: 21 June 2000 / Accepted: 18 July 2000 相似文献
15.
Phytochemical Study of Juglans regia L. Pericarps from Greece with a Chemotaxonomic Approach
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Phytochemical research of different polarity extracts from green Juglans regia L. pericarps from Greece afforded 32 compounds: four pentacyclic triterpenes (1 – 4), three sesquiterpenes (5 – 7), four tetralones (8 – 11), two naphthoquinones (12 and 13), seven phenolic acids (14 – 20), one diarylheptanoid (21), one neo‐lignan (22), seven flavonoids (23 – 29), two phenylethanoids (30 and 31) and one hydrolysed tannin (32). Compounds 4 and 29 are isolated for the first time from the species, while compounds 3, 7, 20, 22, 23, 24, 25, 26, 28, 30 are reported for the first time in Juglandaceae. Chemotaxonomic significance of isolated compounds into Junglandaceae family is thoroughly discussed. 相似文献
16.
Genetic variation in nuclear and mitochondrial markers supports a large sex difference in lifetime reproductive skew in a lekking species
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Yvonne I. Verkuil Cedric Juillet David B. Lank Fredrik Widemo Theunis Piersma 《Ecology and evolution》2014,4(18):3626-3632
Sex differences in skews of vertebrate lifetime reproductive success are difficult to measure directly. Evolutionary histories of differential skew should be detectable in the genome. For example, male‐biased skew should reduce variation in the biparentally inherited genome relative to the maternally inherited genome. We tested this approach in lek‐breeding ruff (Class Aves, Philomachus pugnax) by comparing genetic variation of nuclear microsatellites (θn; biparental) versus mitochondrial D‐loop sequences (θm; maternal), and conversion to comparable nuclear (Ne) and female (Nef) effective population size using published ranges of mutation rates for each marker (μ). We provide a Bayesian method to calculate Ne (θn = 4Neμn) and Nef (θm = 2Nefμm) using 95% credible intervals (CI) of θn and θm as informative priors, and accounting for uncertainty in μ. In 96 male ruffs from one population, Ne was 97% (79–100%) lower than expected under random mating in an ideal population, where Ne:Nef = 2. This substantially lower autosomal variation represents the first genomic support of strong male reproductive skew in a lekking species. 相似文献
17.
Application of desmid diversity in assessing the water quality of 12 freshwater resources in Thailand 总被引:1,自引:0,他引:1
Desmids from 12 freshwater resources in the northern part of Thailand were investigated during 2002 to 2003. A total of 91
taxa were found. They belonged to 17 genera: Actinotaenium, Spirotaenia, Netrium, Gonatozygon, Pleurotaenium, Closterium, Euastrum, Micrasterias, Cosmarium, Cosmocladium, Stuarastrum, Staurodesmus, Xanthidium, Teilingia, Spondylosium, Hyalotheca and Desmidium. The water qualities in all the water resources were classified as oligotrophic to meso-eutrophic by trophic status. The
taxa that could possibly be used as bioindicators of trophic state were Staurastrum gutwinskii, Spondylosium pandurifoemae, Cosmarium capitulum, C. mediosrobiculatum var. egranutum, S. tortum, Closterium gracile var. elongatum, C. kuetzingii and Closterium dianae var. dianae. The most frequently found taxa were Staurastrum limneticum var. burmense, S. tetracerum var. tetraerum, Pleurotaenium trabecula, Closterium ehrenbergii var. ehrenbergii and C. kuetzingii. The rare taxa in this study were Actinotaenium sp. Spirotaenia condensata, Pleurotaenium burmense var. dacchense and Micrasterias apiculata. Forty-one taxa of desmids were identified as new records for Thailand.
Presented at the 6th Meeting of the Asian Pacific Society of Applied Phycology, Manila, Philippines. 相似文献
18.
Tao R Watari A Hanada T Habu T Yaegaki H Yamaguchi M Yamane H 《Plant molecular biology》2007,63(1):109-123
This study demonstrates that self-compatible (SC) peach has mutant versions of S haplotypes that are present in self-incompatible (SI) Prunus species. All three peach S haplotypes, S
1
, S
2
, and S
2m
, found in this study encode mutated pollen determinants, SFB, while only S
2m
has a mutation that affects the function of the pistil determinant S-RNase. A cysteine residue in the C5 domain of the S
2m
-RNase is substituted by a tyrosine residue, thereby reducing RNase stability. The peach SFB mutations are similar to the SFB mutations found in SC haplotypes of sweet cherry (P. avium) and Japanese apricot (P. mume). SFB
1
of the S
1
haplotype, a mutant version of almond (P. dulcis) S
k
haplotype, encodes truncated SFB due to a 155 bp insertion. SFB
2
of the S
2
and S
2m
haplotypes, both of which are mutant versions of the S
a
haplotype in Japanese plum (P. salicina), encodes a truncated SFB due to a 5 bp insertion. Thus, regardless of the functionality of the pistil determinant, all three peach S haplotypes are SC haplotypes. Our finding that peach has mutant versions of S haplotypes that function in almond and Japanese plum, which are phylogenetically close and remote species, respectively, to peach in the subfamily Prunoideae of the Roasaceae, provides insight into the SC/SI evolution in Prunus. We discuss the significance of SC pollen part mutation in peach with special reference to possible differences in the SI mechanisms between Prunus and Solanaceae. 相似文献
19.
Summary The presence of a Ca2+ channel in the plasmalemma of tonoplast-freeNitellopsis obtusa cells was demonstrated and its characteristics were studied using current- and voltage-clamp techniques. A long-lasting inward membrane current (I
m
), recorded using a step voltage clamp, consisted of a single component without time-dependent inactivation. Increasing either [Ca2+]
o
or [Cl–]
o
1) enhanced the maximum amplitude of inwardI
m
((I
m
)
p
) and 2) shifted the peak voltage ((V
m
)
p
) at(I
m
)
p
to more positive values under ramp-shaped voltage clamping and 3) depolarized the peak value of action potentials. This behavior is consistent with predictions based on the Nernst equation for Ca2+ but not for Cl–. DIDS (4,4-diisothiocyano-2,2-disulfonic acid stilbene) did not suppress(I
m
)
p
in tonoplast-free cells, in contrast with its effect on normal cells. La3+ and nifedipine blocked(I
m
)
p
irreversibly. On the other hand, Ca2+ channel agonist, BAY K 8644 irreversibly enhanced(I
m
)
p
. Both Sr2+ influx and K+ efflux increased upon excitation. The charge carried by Sr2+ influx was compensated for by K+ efflux. It is concluded that only the Ca2+ channel is activated during plasmalemma excitation in tonoplast-free cells. In terms of the magnitude of(I
m
)
p
, Sr2+ could replace Ca2+, but Mn2+, Mg2+ and Ba2+ could not. External pH affected(I
m
)
p
and the membrane conductance (g
m
) at(I
m
)
p
((g
m
)
p
). Increasing the external ionic strength caused increases in both(I
m
)
p
and(g
m
)
p
, and shifted(V
m
)
p
to positive values. At the same time, Sr2+ influx increased. Thus Ca2+ channel activation seems to be enhanced by increasing external ionic strength. The possible involvement of surface potential is discussed. 相似文献
20.
K. Okazaki M. Kusaba D. J. Ockendon T. Nishio 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(8):1329-1334
Forty three S tester lines of Brassica oleracea were characterized using DNA and protein gel-blotting analyses. DNA gel-blot analysis of HindIII-digested genomic DNA with class-I and class-II SLG probes revealed that 40 lines could be classified as class-I S haplotypes while three lines could be classified as class-II S haplotypes. The band patterns in the S tester lines were highly polymorphic. Although the S tester lines typically showed two bands corresponding to SLG and SRK in the analysis with the class-I SLG probe, only one band was observed in the S
24
homozygote. This band was identified as SRK, suggesting that this haplotype has no class-I SLG band. In the analysis using the class-II SLG probe, one plant yielded a different band pattern from the known class-II haplotypes, S
2
, S
5
and S
15
. Unexpectedly, this plant was reciprocally cross-incompatible with the S
2
haplotype. Therefore, it was designated as S
2-b
. We found an S
13
haplotype having a restriction fragment length polymorphism different from that of the S
13
homozygotes of the S tester line. These findings indicate that S homozygous lines with the same S specificity do not necessarily show the same band pattern in the DNA gel-blot analysis. Soluble stigma proteins of 32 S homozygotes were separated by isoelectric focusing and detected using anti-S
22
SLG antiserum. S haplotype-specific bands were detected in 27 S homozygotes but not in five S homozygotes, including the S
24
homozygote. This is consistent with the observation that the S
24
haplotype had no SLG band.
Received: 13 July 1998 / Accepted: 29 September 1998 相似文献