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1.
Four new species ofJacaranda have been found in the coastal mountain-ranges of SE-Brazil where they occupy characteristic ecological positions.J. montana andJ. subalpina are related toJ. puberula agg.,J. pulcherrima shows affinities toJ. ulei but also toJ. subalpina. J. crassifolia is very distinct and possibly related toJ. obovata.
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2.
The compositions of leaf monoterpenoids from 11 species in the Juniperus section (Juniperus chinensis var. chinensis,J. virginiana, J. communis var. montana,J. rigida, J. chinensis var. globosa,J. chinensis var. sargentii,J. chinensis ‘Kaizuka Variegata’,J. squamata ‘Wilsonii’,J. x media ‘Shimpake’,J. x media ‘Plamosa Aurea’, andJ. squamata ‘Aloderi’) were comparatively analyzed by GC-MS. Of the 24 compounds identified, α-pinene, myrcene, limonene, terpinolene, and bornyl acetate were common to all, but particular combinations differed remarkably among taxa. The simplest composition (eight compounds) was found in.J, chinensis var. chinensis; the most complex (19 compounds), inJ. x media ‘Shimpake’. Cluster analysis generated four distinctive clades within the Juniperus section. The minimum spanning network revealed thatJ. squamata ‘Wilsonii’ andJ. x media ‘Shimpake’ were most similar in their chemical makeup.  相似文献   

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The genus Jatropha belongs to the family Euphorbiaceae having significant economic importance. The present investigation was undertaken with an aim to understand phylogenetic relationships among seven species (J. curcas, J. glandulifera, J. gossypifolia, J. integerrima, J. multifida, J. podagrica, and J. tanjorensis.) which are widely distributed in India, using nuclear ribosomal DNA ITS sequence (nrDNA ITS) and to compare the results with multilocus marker analysis systems reported earlier for the same genus. The size variation obtained among sequenced nrDNA ITS regions was narrow and ranged from 647 to 654 bp. The overall mean genetic distance (GD) of genus Jatropha was found to be 0.385. Highest interspecific GD (0.419) was found between J. glandulifera and J. multifida. The least interspecific GD (0.085) was found between J. gossypifolia and J. tanjorensis. The highest intraspecific GD was observed in J. podagrica (0.011) and least in J. gossypifolia (0.002). The phylogram obtained using nrDNA ITS sequence showed congruence with the phylograms obtained using multilocus markers system reported earlier with minor variations. The present study also strongly supports high phylogentic closeness of J. curcas and J. integerrima. The only exception found was J. podagrica which clustered with J. multifida in earlier based on multilocus marker analysis, was clustered with J. curcas in the present analysis. The sequence data generated in the present investigation will help for further studies in intraspecies population, and their phylogentic analysis, biogeographical, molecular evolution studies and also pave way for future phylogetic and/or evolution studies among the other groups belongs to the family Euphorbiaceae.  相似文献   

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Despite Juniperus spp. being an important component of Mediterranean arid and semi‐arid ecosystems, there is a lack of complex studies on their biogeographical patterns. Using 16 morphological cone and seed traits and three nuclear microsatellite markers, we investigated the morphological and genetic variability of seven Mediterranean and Macaronesian Juniperus taxa (J. oxycedrus ssp. oxycedrus, J. oxycedrus ssp. badia, J. brevifolia, J. cedrus, J. deltoides, J. macrocarpa and J. navicularis) to identify biogeographical trends and interspecific genetic relationships. The highest gene diversity was measured in J. oxycedrus ssp. oxycedrus (HE = 0.716) and the lowest in J. brevifolia (HE = 0.441). The west Mediterranean was characterized by a higher level of genetic diversity than the east Mediterranean. A lack of significant genetic differences between European and African populations of J. oxycedrus suggests that the Strait of Gibraltar was not a significant barrier to gene flow, but has promoted some morphological differentiation. The genetic and morphological results strongly support the recognition of J. macrocarpa, J. navicularis and J. deltoides at the species rank, whereas J. oxycedrus ssp. badia should be included in J. oxycedrus. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174 , 637–653.  相似文献   

7.
In the order Coniferales, only the family Cupressaceae is regarded as being a significant source of airborne allergens, withJuniperus ashei characterized as the most significat aeroallergen. Pollen of the closely related speciesJ. virginiana has been shown to cross-react withJ. ashei pollen, however,J. virginiana pollen is not considered an important aeroallergen. Although there have been several reports of allergies toPinus pollen, the pollen of this genus is regarded as hypoallergenic. Our previous studies have shown that pollen extracts ofJ. ashei, J. virginiana, J. pinchotii, Cupressus macrocarpa, Pinus echinata andP. taeda all contained several proteins with the same molecular weights including the reported allergen ofJ. ashei. The present study compared the biochemistry ofJ. ashei, J. virginiana andP. echinata pollen. A time course experiment ofJ. ashei, J. virginiana andP. echinata showed thatJ. ashei released a greater quantity of protein within the first minute of moistening. SDS-PAGE analyses showed that the reported allergen ofJ. ashei pollen extracts was released in large quantities within the first minute of extraction. It was also determined that individual pollen grains ofP. echinata contained a greater quantity of protein than the pollen ofJ. ashei andJ. virginiana, but due to the large size of pine pollen there was less protein per gram of pollen. Lipid analysis of these three taxa showed that the pollen ofP. echinata contained more lipid per grain and per gram of pollen. Results indicate that the rapid release of the reported allergen fromJ. ashei pollen contributes to the allergenicity of this species compared to bothJ. virginiana andP. echinata.  相似文献   

8.
Oil samples from six species of Juniperus include 37 detected components, of which most are quantitatively highly variable. Nine chromatographic patterns were identified, including one for each of two subspecies of J. occidentalis and, surprisingly, two different patterns in both J. californica and J. monosperma. The chemical evidence supports earlier taxonomic conclusions based on morphology and natural history that J. occidentalis subsp. occidentalis and J. occidentalis subsp. australis are indeed subspecies, that the former is intermediate between the latter and J. osteosperma, and that J. californica and J. osteosperma are closely related but distinct species. It is concluded that the techniques of gas chromatography have considerable potential as a taxonomic tool.  相似文献   

9.
Random amplified polymorphic DNAs (RAPDs) and leaf volatile terpenoids were used to compare junipers from Abha, Saudi Arabia with J. excelsa from Greece and J. procera from Addis Ababa, Ethiopia. Both the RAPDs and terpenoids clearly identified the Abha juniper as J. procera. The migration and evolution of J. excelsa or pre-J. excelsa junipers southward from Asia Minor into Africa is discussed. A computer program, PCO3D, is now available for 3-D ordination of RAPDs data. In addition, this research supports the recognition of both J. excelsa and J. procera as separate species.  相似文献   

10.
Fourteen new species of palms (Arecaceae) from Madagascar are described and named, based on material collected over the last 15 years. Twelve species belong to the genus Dypsis, namely D. andilamenensis Rakotoarin. & J. Dransf., D. anjae Rakotoarin. & J. Dransf., D. betsimisarakae Rakotoarin. & J. Dransf., D. culminis Rakotoarin. & J. Dransf., D. dracaenoides Rakotoarin. & J. Dransf., D. gautieri Rakotoarin. & J. Dransf., D. gronophyllum Rakotoarin. & J. Dransf., D. jeremiei Rakotoarin. & J. Dransf., D. metallica Rakotoarin. & J. Dransf., D. reflexa Rakotoarin. & J. Dransf., D. sancta Rakotoarin. & J. Dransf. and D. vonitrandambo Rakotoarin. & J. Dransf. and two species belong to the genus Ravenea: R. beentjei Rakotoarin. & J. Dransf. and R. hypoleuca Rakotoarin. & J. Dransf. Despite the fact that most of these species have been recorded from protected areas that are difficult to access in the eastern region of Madagasacar, they are all threatened. Based on IUCN categories and criteria, seven are Critically Endangered and seven are Vulnerable.  相似文献   

11.
A survey of the tribe Justicieae from the Caatinga biome, in the State of Bahia, revealed the following four new species of Justicia (Acanthaceae): J. angustissima, J. attenuata, J. chlamidocalyx and J. jacuipensis. J. attenuata and J. jacuipensis are known only from the types; the latter is considered Critically Endangered (CR) because the area where it was collected has been flooded since the construction of the Pedra do Cavalo dam and the region around this area has been extensively disturbed. J. angustissima and J. chlamidocalyx were found in six locations. They have a wide distribution in Central Bahia and the conservation status of both species should be classified as Least Concern (LC). The four species are described and illustrations and comments are provided.  相似文献   

12.
The present investigation was undertaken with an aim to check the ability of cross species amplification of microsatellite markers isolated from Jatropha curcas—a renewable source of biodiesel to deduce the generic relationship with its six sister taxa (J. glandulifera, J. gossypifolia, J. integerrima, J. multifida, J. podagrica, and J. tanjorensis). Out of the 49 markers checked 31 markers showed cross species amplification in all the species studied. JCDS-30, JCDS-69, JCDS-26, JCMS-13 and JCMS-21 amplified in J. curcas. However, these markers did not show any cross species amplification. Overall percentage of polymorphism (PP) among the species studied was 38% and the mean genetic similarity (GS) was found to be 0.86. The highest PP (24) and least GS (0.76) was found between J. curcas/J. podagrica and J. curcas/J. multifida and least PP (4.44) and highest GS (0.96) was found between J. integerrima/J. tanjorensis. Dendrogram analysis showed good congruence to RAPD and AFLP than nrDNA ITS data reported earlier. The characterized microsatellites will pave way for intraspecies molecular characterization which can be further utilized in species differentiation, molecular identification, characterization of interspecific hybrids, exploitation of genetic resource management and genetic improvement of the species through marker assisted breeding for economically important traits.  相似文献   

13.
The high‐Andean genus Jivarus Giglio‐Tos from Ecuador, Colombia and Peru is revised. Morphological cladistic analysis indicated that Jivarus montanus and the new species digiticercus sp.n. and rugosus sp.n. must be treated as a separate genus, Maylasacris gen.n. The remaining species included in the analysis are assigned to the genus Jivarus, for which the following six species groups are identified: americanus group, antisanae group, carbonelli group, cohni group, pictifrons group and jagoi group. Twenty‐nine species are recognized for Jivarus, with ten described as new: J. rectus sp.n. , J. megacercus sp.n. , J. spatulus sp . n. , J. auriculus sp.n. , J. riveti sp.n. , J. sphaericus sp.n. , J. discoloris sp . n. , J. profundus sp.n. , J. ronderosi sp.n. and J. guarandaensis sp.n. The following new synonymies are proposed: Jivarus albolineatus Ronderos with J. antisanae (Bolivar) syn.n. , J. cerdai Ronderos and J. osunai Ronderos with J. alienus (Walker) syn.n. , and J. rubriventris Ronderos with J. ecuadorica (Hebard) syn.n. ; the new combinations Jivarus ecuadorica (Ronderos) comb.n. and Maylasacris montanus (Ronderos) comb.n. are proposed. Keys to the species of the genera and a review of the morphological characters defining the taxa are provided. Patterns of distribution of the clades coincide with the geography of the northern Andes of Colombia and Ecuador. Areas of endemism of the Jivarus species groups and Maylasacris are delimited by both the high‐altitude curves, including transverse zones, and the drier climates of the intra‐Andean valleys, clearly indicating recent, post‐glacial palaeogeography, as shown also in vegetation distributions. This paper has been formatted with many embedded links to images of type and paratype specimens, maps based on geo‐referenced specimen data and species keys available on the Orthoptera Species file online ( http://orthoptera.speciesfile.org ).  相似文献   

14.
The sexual phase of three species of Jamesonia (J. imbricata, J. rotundifolia and J. scammaniae) has been studied, from spore germination to gametangia formation, with special attention to the morphological development of prothalli. This is the first work to deal with gametophytes of species in this genus. All three species have trilete, tetrahedrical spores that germinate following the Vittaria type. The developmental pattern of J. imbricata and J. rotundifolia is intermediate between the Adiantum and Ceratopteris types, as the initial mitotic activity is assumed by an obconical apical cell, substituted later by a lateral meristem. In J. scammaniae, no apical cell or lateral meristem is formed, so the prothalli remain ameristic throughout the developmental process. Adult gametophytes are naked and variable in shape, in the same species ranging from typical cordate prothalli to irregularly lobed forms. Gametangia of normal shape and size was observed in both J. imbricata and J. rotundifolia, but not in J. scammaniae. Apogamy could be expected to occur in the genus, a phenomenon to be examined in the future. Comparisons are made with known species of related genera and results are discussed from an ecological perspective in the paramo environment.  相似文献   

15.
Genus Jatropha with 172 species having significant economic importance belongs to the family Euphorbiaceae. There are no reports on molecular characterization and phylogenetic relationship among the species of Jatropha. Hence, the present study was undertaken to assess the extent of genetic variability that exist and also to establish phylogenetic relationship among Jatropha curcas, J. glandulifera, J. gossypifolia, J. integerrima, J. multifida, J. podagrica and J. tanjorensis using RAPD and AFLP. The percentage of loci that are polymorphic among the species studied was found to be 97.74% by RAPD and 97.25% by AFLP. The mean percentage of polymorphism (PP) was found to be 68.48 by RAPD and 71.33 by AFLP. The phylogram generated with RAPD and AFLP data showed maximum similarity. With the generated data maximum relatedness was found between J. curcas and J. integerrima this may be the reason for the success of inter hybrid crosses between these two species. Neither RAPD nor AFLP data generated in this study supports the view of J. tanjorensis, a natural interspecific hybrid between J. curcas and J. gossypifolia. The present study concludes that both RAPD and AFLP techniques are comparable in divergence studies of Jatropha species. The markers generated by RAPD and AFLP can be employed efficiently for interspecific hybrids identification, marker assisted selection and genetic resource management.  相似文献   

16.
Enzyme electrophoresis was used to estimate genetic diversity and population structure of Juniperus rigida (Cupressaceae) and Juniperus coreana in Korea. In J. rigida, 16 of the 22 loci (72.7%) showed detectable polymorphism. Genetic diversity (0.224) was higher than average values for species with similar life history traits. The endemic species (J. coreana) was found to have fewer alleles per locus (1.39 vs. 1.61), fewer alleles per polymorphic locus (2.42 vs. 2.63), lower percent polymorphic locus (54.6 vs. 72.7%), and lower diversity (0.199 vs. 0.224) than J. rigida. These genetic diversity parameters indicated that J. coreana was genetically depauperate relative to its presumptive progenitor, J. rigida. Analysis of fixation indices showed a substantial deficiency of heterozygotes relative to Hardy–Weinberg expectations suggesting inbreeding in J. coreana. The G ST values of J. rigida and J. coreana were 0.173 and 0.118 respectively. The indirect estimate of gene flow based on mean G ST was moderate (Nm = 1.19 for J. rigida and 1.86 for J. coreana). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
Displacement of native plant species by non‐indigenous congeners may affect associated faunal assemblages. In endangered salt marshes of south‐east Australia, the non‐indigenous rush Juncus acutus is currently displacing the native rush Juncus kraussii, which is a dominant habitat‐forming species along the upper border of coastal salt marshes. We sampled insect assemblages on multiple plants of these congeneric rushes in coastal salt marshes in Sydney, New South Wales, Australia, and compared the abundance, richness, diversity, composition and trophic structure between: (i) J. acutus and J. kraussii at invaded locations; and (ii) J. kraussii at locations either invaded or not invaded by J. acutus. Although J. acutus supported a diverse suite of insects, species richness and diversity were significantly greater on the native J. kraussii. Moreover, insect assemblages associated with J. kraussii at sites invaded by J. acutus were significantly different from, and more variable than, those on J. kraussii at non‐invaded sites. The trophic structure of the insect assemblages was also different, including the abundance and richness of predators and herbivores, suggesting that J. acutus may be altering consumer interactions, and may be spreading in part because of a reduction in herbivory. This strongly suggests that J. acutus is not playing a functionally similar role to J. kraussii with respect to the plant‐associated insect species assemblages. Consequently, at sites where this non‐indigenous species successfully displaces the native congener, this may have important ecological consequences for community composition and functioning of these endangered coastal salt marshes.  相似文献   

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In pepper plants (genus Capsicum), the resistance against Tobamovirus spp. is conferred by L gene alleles. The recently identified L variant L1a can recognize coat proteins (CPs) of Tobacco mild green mosaic virus Japanese strain (TMGMV‐J) and Paprika mild mottle virus Japanese strain (PaMMV‐J), but not of Pepper mild mottle virus (PMMoV), as the elicitor to induce resistance at 24 °C. Interestingly, L1a gene‐mediated resistance against TMGMV‐J, but not PaMMV‐J, is retained at 30 °C. This observation led us to speculate that L1a can discriminate between CPs of TMGMV‐J and PaMMV‐J. In this study, we aimed to determine the region(s) in CP by which L1a distinguishes TMGMV‐J from PaMMV‐J. By using chimeric CPs consisting of TMGMV‐J and PaMMV‐J, we found that the chimeric TMGMV‐J CP, whose residues in the β‐sheet domain were replaced by those of PaMMV‐J, lost its ability to induce L1a gene‐mediated resistance at 30 °C. In contrast, the chimeric PaMMV‐J CP with the β‐sheet domain replaced by TMGMV‐J CP was able to induce L1a gene‐mediated resistance at 30 °C. Furthermore, viral particles were not detected in the leaves inoculated with either chimeric virus. These observations indicated that the amino acids within the β‐sheet domain were involved in both the induction of L1a gene‐mediated resistance and virion formation. Further analyses using chimeric CPs of TMGMV‐J and PMMoV indicated that amino acids within the β‐sheet domain alone were not sufficient for the induction of L1a gene‐mediated resistance by TMGMV‐J CP. These results suggest that multiple regions in Tobamovirus CP are implicated in the induction of L1a gene‐mediated resistance.  相似文献   

20.
The genetic diversity among eight Jatropha species and three Jatropha curcas accessions were analyzed using ISSR-PCR. Nine ISSR primers generated reproducible amplification banding pattern of 61 polymorphic bands out of 64 scored accounting for 98.14% polymorphism across the species. The ISSR primers viz., I1, I2, I3, I4, I5, I6, I7 and I10 generated 100% polymorphic patterns. Jaccard’s coefficient of similarity varied from 0.346 to 0.807, indicative of high level of genetic variation among the genotypes studied. The UPGMA cluster analysis indicated three distinct clusters, one comprising all accessions of J. curcas L (TNMJ1, TNMJ 22 and TNMJ 23), while second included four species viz., J. tanjorensis J. L. Ellis et Saroja., J. gossypifolia L., J. podagrica Hook and J. maheshwarii Subrum and M.P. Nayer and the third cluster included another four species viz., J. villosa Wight J. multifida L., J. integerrima Jacq and J. glandulifera Roxb. The overall grouping pattern of clustering corresponds well with principal component analysis (PCA) confirming patterns of genetic diversity observed among the species. So far, there are no reports on the molecular diversity of the Jatropha species through ISSR marker. This study provides valid guidelines for collection, conservation and characterization of Jatropha genetic resources and also for further breeding programme towards biodiesel production.  相似文献   

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