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1.
CLARENCE STERLING F.L.S 《Botanical journal of the Linnean Society. Linnean Society of London》1974,68(4):283-290
The pistil in the flowers of the Iphigenieae (Camptorrhiza, Iphigenia, Omithoglossum) is usually tricarpellate. The carpels are coherent generally, with closed sutures and seemingly bitegmic ovules. Camptorrhiza differs from the others in having a single compound style. The pistils of most species of these genera have a common vascular structure: three dorsal bundles which run into the style(s), a number of lateral bundles, six placental bundles, and up to three compound septal bundles. The latter nine bundles usually differentiate from a central vascular plexus above the base of the locules. There may be fewer than three septal bundles in some specieS. When present, the septal bundles usually die out in the ovuliferous region, but in some cases they persist to the apex of the locules. 相似文献
2.
Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a positive relationship between pollen size and style length.Five floral traits were observed to be correlated among42 bumblebee-pollinated Pedicularis species(Orobanchaceae) in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin's functional hypothesis between pollen size and stigma depth. 相似文献
3.
K. W. Hilu 《Genetics》1988,118(1):163-167
Finger millet (Eleusine corocana subsp. coracana), an important cereal in East Africa and India, is a tetraploid species with unknown genomic components. A recent cytogenetic study confirmed the direct origin of this millet from the tetraploid E. coracana subsp. africana but questioned Eleusine indica as a genomic donor. Chloroplast (ct) DNA sequence analysis using restriction fragment pattern was used to examine the phylogenetic relationships between E. coracana subsp. coracana (domesticated finger millet), E. coracana subspecies africana (wild finger millet), and E. indica. Eleusine tristachya was included since it is the only other annual diploid species in the genus with a basic chromosome number of x = 9 like finger millet. Eight of the ten restriction endonucleases used had 16 to over 30 restriction sites per genome and were informative. E. coracana subsp. coracana and subsp. africana and E. indica were identical in all the restriction sites surveyed, while the ct genome of E. tristachya differed consistently by at least one mutational event for each restriction enzyme surveyed. This random survey of the ct genomes of these species points out E. indica as one of the genome donors (maternal genome donor) of domesticated finger millet contrary to a previous cytogenetic study. The data also substantiate E. coracana subsp. africana as the progenitor of domesticated finger millet. The disparity between the cytogenetic and the molecular approaches is discussed in light of the problems associated with chromosome pairing and polyploidy. 相似文献
4.
Armillaria root rot is a serious disease, chiefly of woody plants, caused by many species of Armillaria that occur in temperate, tropical and subtropical regions of the world. Very little is known about Armillaria in South America and Southeast Asia, although Armillaria root rot is well known in these areas. In this study, we consider previously unidentified isolates collected from trees with symptoms of Armillaria root rot in Chile, Indonesia and Malaysia. In addition, isolates from basidiocarps resembling A. novae-zelandiae and A. limonea, originating from Chile and Argentina, respectively, were included in this study because their true identity has been uncertain. All isolates in this study were compared, based on their similarity in ITS sequences with previously sequenced Armillaria species, and their phylogenetic relationship with species from the Southern Hemisphere was considered. ITS sequence data for Armillaria also were compared with those available at GenBank. Parsimony and distance analyses were conducted to determine the phylogenetic relationships between the unknown isolates and the species that showed high ITS sequence similarity. In addition, IGS-1 sequence data were obtained for some of the species to validate the trees obtained from the ITS data set. Results of this study showed that the ITS sequences of the isolates obtained from basidiocarps resembling A. novae-zelandiae are most similar to those for this species. ITS sequences for isolates from Indonesia and Malaysia had the highest similarity to A. novae-zelandiae but were phylogenetically separated from this species. Isolates from Chile, for which basidiocarps were not found, were similar in their ITS and IGS-1 sequences to the isolate from Argentina that resembled A. limonea. These isolates, however, had the highest ITS and IGS-1 sequence similarity to authentic isolates of A. luteobubalina and were phylogenetically more closely related to this species than to A. limonea. 相似文献
5.
Brooks DR 《The Journal of parasitology》2004,90(3):594-597
The species recently described as Acanthostomum macroclemidis possesses the gonotyl in the form of a solid muscular pad uniquely diagnostic for species of Proctocaecum and is accordingly transferred to that genus. An artificial key to the 5 acanthostomine genera, as well as an updated phylogenetic hypothesis for the 10 known species of Proctocaecum, based on 11 characters and including 2 species described since the last phylogenetic analysis, are presented. The single most parsimonious phylogenetic tree with a consistency index of 87.5% suggests that Proctocaecum originated in Africa and spread to North America and South America before the breakup of Pangaea. As a result, the 2 North American and 1 South American species are most closely related to different African members of the genus. African and Indo-Pacific species inhabit crocodylids; hence, the occurrence of North American species in alligatorids and chelonians and a South American species in alligatorids are the result of host switches. 相似文献
6.
GC-MS analysis of Iphigenia stellata Blatter in methanol extract revealed the presence of twenty chemical compounds in corm, nine in capsule wall, seven in leaves and six in seeds. Amongst the different phytochemicals identified 2-furan-carboxaldehyde-5-(hydroxymethyl) (38% in corms), glycerine (35.4% in seeds) and n-hexadecanoic acid (31.5% in leaves, 28%) in capsule wall) were significant. Iphigenia stellata is known for the presence of colchicine. However, in the methanol extract it was not detected. 相似文献
7.
Patterns of morphological variation in the Burmannia coelestis species complex are investigated, and three distinct species recognized. Burmannia coelestis sensu stricto (widespread in Asia, extending from eastern Nepal and Assam to New Guinea and northern Australia) possesses outer perianth lobes with conspicuous double margins running the entire lengths of the lobes. The name B. chinensis is revived for specimens from north-eastern India, southern China, northern Indochina and northern Thailand which possess outer perianth lobes with single margins or short double margins. A new species, B. filamentosa , is described from Guangdong province, China; it is distinctive in possessing narrow triangular outer and inner perianth lobes, and stamens with prominent filaments. 相似文献
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9.
M. Sivadasan 《Plant Systematics and Evolution》1986,153(3-4):165-170
Amorphophallus nicolsonianus species nova, with cylindrical or napiform corms, is the only representative of the sect.Rapyogkos in India. All the other hitherto known species of this region have globose or depressed globose corms. The new species is related to some Indochinese species and toA. hildebrandtii (
Engl.)Engl. & Gehrm. from Madagascar. 相似文献
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11.
L. Baldoni C. Guerrero K. Sossey-Aloui A. G. Abbott A. Angiolillo R. Lumaret 《Plant biology (Stuttgart, Germany)》2002,4(3):346-351
Abstract: The purpose of this study was to assess nucleotide variation at a non-coding chloroplast DNA region in Olea species, to evaluate their phylogenetic relationships within the Olea genus and, more particularly, to clarify the relationships between cultivated olive (O. europaea) and the other taxa of section Olea. The analysis was made on an intergenic region between the trnT (UGU) and trnL (UAA) 5' exon, within a large single copy region of the chloroplast genome. Site-specific primers were used to amplify the region by PCR. This sequence analysis was applied to the same array of Olea species as assayed by Lumaret et al. (2000[16] ) using cpDNA RFLPs, thus making it possible to compare phylogenetic relationships analysed at two complementary levels of cpDNA variation. On the 666 bp aligned sequence, 8 different haplotypes were defined, with 9 single nucleotide mutations, a different length of a poly-T region and an indel for O. paniculata. Haplotypes were shared by the species pairs O. europaea-O.laperrinei, O. maroccana-O. cerasiformis, O. capensis-O. lancea and O. africana-O.indica. Phylogenetic analyses of these data distinguished four groups: the species Olea capensis and O. lancea, which both belong to subgenus Ligustroides, the Olea forms from southeast Africa, those from Asia and the taxa of northwest Africa and the Mediterranean Basin, which include olive crop. The results are consistent with those previously found using cpDNA RFLPs, with some minor differences observed within each group. They constitute further evidence to clarify the phylogeny of Olea. 相似文献
12.
利用多基因序列探讨稻属药稻复合体二倍体物种的系统发育关系 总被引:12,自引:2,他引:10
稻属药稻复合体Oryza officinalis complex中有5个二倍体物种,涉及B、C和E3个染色体组,分布在亚洲、非洲和大洋洲。其中,O.australiensis是稻属中惟一含E染色体组的物种;O.punctata则是惟一含B染色体组的物种。虽然O.officinalis、O.rhizomatis和O.eichingeri都含C染色体组,但由于它们间断分布在亚洲和非洲,可能在稻属异源多倍体成种中发挥了不同作用。染色体组B、C和E之间,以及上述二倍体物种之间的系统发育关系及其在稻属多倍体物种形成 相似文献
13.
Two species of Camellia L. (Theaceae) are described here as new: C. curryana and C. longii. The new species were discovered in the southern Annamite Mountains of Vietnam and are endemic to tropical rainforest remnants that occur at altitudes between 1500 and 1700 m a.s.l. Camellia curryana possesses almost sessile, unevenly circular, two whorled, white‐cream and proximally yellowish flowers, proximally joined outer stamens, three styles and mature fruit that dehisces into three parts, or longitudinally into two halves. Camellia longii has campanulate or almost campanulate, intensely dark orange to red flowers with uneven whitish margins, 5–6 petals and 3–2 petaloids, filaments that are united with the petals and one another, a diamond shaped ovary and compound 5–6 styles that are connate at the base. 相似文献
14.
钾对番红花球茎膨大的生理生态效应 总被引:3,自引:0,他引:3
名贵中药番红花球茎的大小是决定其入药器官—柱头多少的关键,用4个不同K水平的营养液培养番红花,结果表明,随着施钾水平的提高,叶片中的钾含量、叶绿素含量、ATP相对含量及叶片净光合速率也相应提高,使得叶片作为“代谢源”的能力加强.随着施钾水平提高,新球茎富集钾的能力、可溶性糖含量、Vc含量和蛋白质含量也增加,致使新球茎作为“代谢库”的功能也增强,球茎膨大速率加快,本文对钾元素通过加强“源”和“库”的功能来提高番红花球茎膨大速率的机理进行探讨,为番红花的进一步研究与利用提供了新的依据。 相似文献
15.
Dowling AP Ochoa R Beard JJ Welbourn WC Ueckermann EA 《Experimental & applied acarology》2012,57(3-4):257-269
The genus Raoiella is best known because of the red palm mite, R. indica, a major pest of palms spreading aggressively throughout the Americas. Not much was known about the biology, geographic origins, or evolutionary history of the genus when R. indica emerged as a major invasive pest. This paper attempts to address some of the basic historical questions regarding the palm mite as well as the genus. Molecular characters from COI and 28S regions were used to produce a phylogenetic hypothesis for the genus in an effort to understand its geographic origin. It also uses COI barcode data to delimit several potentially new species discovered by the authors in Australia. Results show a basal split between R. indica and all other Raoiella species, which indicates Africa or the Middle East as the most probable origin of the genus. Additionally, COI data suggests that at least eight new species are represented among the 20 Australian populations included in this study. 相似文献
16.
Developmental and stress regulation of gene expression for a 9-cis-epoxycarotenoid dioxygenase, CstNCED, isolated from Crocus sativus stigmas 总被引:1,自引:0,他引:1
Oxidative cleavage of cis-epoxycarotenoids by 9-cis-epoxycarotenoid dioxygenase (NCED) is the critical step in the regulation of abscisic acid (ABA) synthesis in higher plants. ABA has been associated with dormancy and flower senescence, while also regulating plant adaptive responses to various environmental stresses. An NCED gene, CstNCED, was cloned from Crocus sativus stigmas. The deduced amino acid sequence of the CstNCED protein shared high identity with other monocot NCEDs, and was closely related to the liliopsida enzymes. At the N-terminus of CstNCED a chloroplast transit peptide sequence is located. However, its expression in chloroplast-free tissues suggested localization in other plastid types. The relationship between expression of CstNCED and the endogenous ABA level was investigated in the stigma and corms, where it was developmentally regulated. The senescence of the unpollinated stigma is preceded by an increase in ABA levels and CstNCED expression. In corms, a correlation was observed between CstNCED expression and dormancy. Furthermore, CstNCED expression was correlated with the presence of zeaxanthin in the dormant corms. When detached C. sativus leaves and stigmas were water and salt stressed, increases in CstNCED mRNA were observed. The results provided evidence of the involvement of CstNCED in the regulation of ABA-associated processes such as flower senescence and corm dormancy in monocotyledonous saffron. 相似文献
17.
云南丽江山慈菇遗传多样性的DALP分析 总被引:6,自引:0,他引:6
采用DALP (Direct amplification of length polymorphism) 分子标记技术, 对产自云南的药用植物丽江山慈菇Iphigenia indica (L.) Kunth的9个居群进行DNA指纹检测。筛选出5个引物组合, 扩增共产生131条DNA片段, 其中104 条谱带具有遗传多态性, 约占79 39%, 平均每组引物扩增所得多态条带为20 8, 9个居群平均多态百分率为42 21%。9个居群平均观察等位基因数Na为1 4224, 总Na为1 7939; 平均有效等位基因数Ne 为1 3141, 总Ne 为1 4810; 平均遗传多样性指数H为0 1745, 总H为0 2831; 平均Shannon 多样性指数I 为0 2527, 总I为0 4231; 总基因多样性Ht为0 2831, 居群内多样性Hs 为0 1745, 居群间基因分化系数Gst为0 3834, 即丽江山慈菇有61 66%的遗传变异来自居群内, 38 34%来自居群间, 居群间存在较高水平的遗传分化。滇西北居群的遗传多样性明显高于滇中居群的遗传多样性, 这与滇中地区丽江山慈菇野生资源被大规模挖掘有着直接的关系。 相似文献
18.
R. K. Aggarwal T. Kivisild J. Ramadevi L. Singh 《Journal of Zoological Systematics and Evolutionary Research》2007,45(2):163-172
Two small endangered populations of Indian wolves were recently shown to be distant from other wolf and dog mtDNA lineages characterized so far. None of the inner branches in the tree of canid species based on partial hypervariable D-loop sequences were, however, statistically supported by the data raising the question whether the two Indian wolf lineages represent two new species, occupying an intermediate position between Canis latrans and C. lupus or have diverged from the sub-species of C. lupus due to isolation and drift. Here we report complete D-loop, cytochrome b, and 16S rRNA sequences data for 23 additional wolves from India analysed in the context of other canid species. Extended analyses of D-loop data and partial sequences of 16S rRNA showed highly reticulated pattern and were unable to resolve unambiguously the phylogenetic relationship of Indian wolves among other canid species. The phylogenetic reconstructions of cytochrome b sequences, however gave significant statistical support for the inner branches supporting genetic distinction of the two Indian wolf lineages within themselves as well as from all other wolves of the world, including individuals belonging to subspecies C. lupus chanco and C. lupus pallipes to which the two Indian wolf populations have been traditionally assigned. Their genetic differentiation relative to worldwide variation of wolves supports the suggestion to treat them as separate wolf species, C. himalayensis and C. indica . 相似文献
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Marcin Piątek Kai Riess Dariusz Karasiński Nourou S. Yorou Matthias Lutz 《Organisms Diversity & Evolution》2016,16(4):743-760
The order Ceraceosorales (Ustilaginomycotina) currently includes the single genus Ceraceosorus, with one species, Ceraceosorus bombacis, parasitic on Bombax ceiba in India. The diversity, biogeography, evolution, and phylogenetic relationships of this order are still relatively unknown. Here, a second species of Ceraceosorus is described from West Africa as a novel species, Ceraceosorus africanus, infecting Bombax costatum in Benin, Ghana, and Togo. This species produces conspicuous fructifications, similar to corticioid basidiomata when mature, but sorus-like in early stages of ontogenetic development. The fructifications cover much of the leaf surface and resemble leaf blight. This contrasts with the inconspicuous fructifications of C. bombacis comprising small spots scattered over the lower leaf surface that resemble leaf spot. Both species of Ceraceosorus differ in several micromorphological traits, infect different host plant species in widely separated geographical areas, and are separated by a considerable genetic distance in 28S rDNA and RPB2 genes. The distinct corticioid fructification of C. africanus is a unique morphological trait within the Ustilaginomycotina. Molecular phylogenetic analyses of a single gene dataset (D1/D2 28S rDNA) supported the monophyly of the two Ceraceosorus species and the Ceraceosorales and their placement within the Ustilaginomycotina. Molecular phylogenetic analyses of a multigene dataset (18S/5.8S/28S rDNA/RPB2/TEF1) revealed Exobasidium rhododendri (Exobasidiales) as the closest relative of Ceraceosorus, both clustering together with Entyloma calendulae (Entylomatales), indicating affinities to the Exobasidiomycetes. This phylogenetic placement is in agreement with ultrastructural characteristics (presence of local interaction zone and interaction apparatus) reported for the Ceraceosorales, Entylomatales, and Exobasidiales. 相似文献