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1.
2.
A taxonomic revision ofCordylanthus subg.Hemistegia based on evidence from morphology, chromosome numbers, habitat, ecology, and geographic distribution is presented, recognizing four species and five subspecies. Three new combinations on the subspecific level are proposed. The first chromosome counts for subg.Hemistegia are reported with haploid numbers ofn = 14, 15, and 21. Each species is illustrated with line drawings showing habit and floral morphology; distribution maps indicate sites of known populations. The possible extinction ofC. mollis ssp.mollis andC. pamatus is discussed, and the urgent need for preservation of their saline and alkaline habitats is emphasized.  相似文献   

3.
Leymus mollis (2n = 4x = 28, NsNsXmXm) possesses novel and important genes for resistance against multi-fungal diseases. The development of new wheat—L. mollis introgression lines is of great significance for wheat disease resistance breeding. M11003-3-1-15-8, a novel disomic substitution line of common wheat cv. 7182 –L. mollis, developed and selected from the BC1F5 progeny between wheat cv. 7182 and octoploid Tritileymus M47 (2n = 8x = 56, AABBDDNsNs), was characterized by morphological and cytogenetic identification, analysis of functional molecular markers, genomic in situ hybridization (GISH), sequential fluorescence in situ hybridization (FISH)—genomic in situ hybridization (GISH) and disease resistance evaluation. Cytological observations suggested that M11003-3-1-15-8 contained 42 chromosomes and formed 21 bivalents at meiotic metaphase I. The GISH investigations showed that line contained 40 wheat chromosomes and a pair of L. mollis chromosomes. EST-STS multiple loci markers and PLUG (PCR-based Landmark Unique Gene) markers confirmed that the introduced L. mollis chromosomes belonged to homoeologous group 7, it was designated as Lm#7Ns. While nulli-tetrasomic and sequential FISH-GISH analysis using the oligonucleotide Oligo-pSc119.2 and Oligo-pTa535 as probes revealed that the wheat 7D chromosomes were absent in M11003-3-1-15-8. Therefore, it was deduced that M11003-3-1-15-8 was a wheat–L. mollis Lm#7Ns (7D) disomic substitution line. Field disease resistance demonstrated that the introduced L. mollis chromosomes Lm#7Ns were responsible for the stripe rust resistance at the adult stage. Moreover, M11003-3-1-15-8 had a superior numbers of florets. The novel disomic substitution line M11003-3-1-15-8, could be exploited as an important genetic material in wheat resistance breeding programs and genetic resources.  相似文献   

4.
Bacterial communities of marine sponges are believed to be an important partner for host survival but remain poorly studied. Sponges show difference in richness and abundance of microbial population inhabiting them. Three marine sponges belonging to the species of Pione vastifica, Siphonochalina siphonella and Suberea mollis were collected from Red sea in Jeddah and were investigated using high throughput sequencing. Highly diverse communities containing 105 OTUs were identified in S. mollis host. Only 61 and 43 OTUs were found in P. vastifica and S. siphonella respectively. We identified 10 different bacterial phyla and 31 genera using 27,356 sequences. Most of the OTUs belong to phylum Proteobacteria (29%–99%) comprising of Gammaproteobacteria, Alphaproteobacteria, and Deltaproteobacteria where later two were only detected in HMA sponge, S. mollis. A number of 16S rRNA sequences (25%) were not identified to phylum level and may be novel taxa. Richness of bacterial community and Shannon, Simpson diversity revealed that sponge S. mollis harbors high diversity compared to other two LMA sponges. Dominance of Proteobacteria in sponges may indicate an ecological significance of this phylum in the Red sea sponges. These differences in bacterial composition may be due to difference in location site or host responses to environmental conditions. To the best of our knowledge, the microbial communities of these sponges have never been studied before and this is first attempt to unravel bacterial diversity using PCR-based 454-pyrosequencing method.  相似文献   

5.
Abiotic drivers of environmental stress have been found to induce CAM expression (nocturnal carboxylation) in facultative CAM species such as Mesembryanthemum crystallinum. The role played by biotic factors such as competition with non-CAM species in affecting CAM expression, however, remains largely understudied. This research investigated the effects of salt and water conditions on the competition between M. crystallinum and the C3 grass Bromus mollis with which it is found to coexist in California’s coastal grasslands. We also investigated the extent to which CAM expression in M. crystallinum was affected by the intensity of the competition with B. mollis. We found that M. crystallinum had a competitive advantage over B. mollis in drought and saline conditions, while B. mollis exerted strong competitive effects on M. crystallinum in access to light and soil nutrients in high water conditions. This strong competitive effect even outweighed the favorable effects of salt or water additions in increasing the biomass and productivity of M. crystallinum in mixture. Regardless of salt conditions, M. crystallinum did not switch to CAM photosynthesis in response to this strong competitive effect from B. mollis. Disturbance (i.e., grass cutting) reduced the competitive pressure by B. mollis and allowed for CAM expression in M. crystallinum when it was grown mixed with B. mollis. We suggest that moderate competition with other functional groups can enhance CAM expression in M. crystallinum, thereby affecting its plasticity and ability to cope with biological stress.  相似文献   

6.
《Phytochemistry》1986,25(12):2901-2903
Twenty-eight flavonoid aglycones have been identified from Arnica chamissonis, A. longifolia, A. amplexicaulis, A. mollis, and A. parryi of the subgenus Chamissonis of the genus Arnica. The flavonoid pattern was largely homogeneous. Only A. mollis is an exception by the occurrence of 7-methylation.  相似文献   

7.
《Phytochemistry》1986,25(10):2423-2424
The flavonoids of Fagonia taeckholmiana and four varieties of F. arabica were investigated. Six flavonoids were identified: isorhamnetin 3-glucoside and 3-rutinoside, herbacetin 8-rutinoside, herbacetin 8-methyl ether-3-rutinoside, 3,7-diglucoside and 3-rutinoside-7-glucoside.  相似文献   

8.
Chromosome number determinations were made from 407 wild or transplanted individuals and seedlings representing 65 taxa and hybrids inEuthamia andSolidago. The following are first reports:Euthamia remota, 2n=9II;Solidago leavenworthii, 2n=54;S. mollis, 2n=36;S. mollis var.angustata, 2n=36;S. rigida var.glabrata, 2n=9II;S. sempervirens var.azorica, 2n=9II; andS. sparsiflora, 2n=54. Most species have been sampled only a few times or are consistently of one cytotype. Sufficient counts have been made to indicate some general patterns of cytotype distribution in the following species complexes:S. gigantea, S. canadensis, S. flexicaulis, S. rugosa, andS. uliginosa.  相似文献   

9.
Rapid, reversible colour change is unusual in animals, but is a feature of male chameleon grasshoppers (Kosciuscola tristis). Understanding what triggers this colour change is paramount to developing hypotheses explaining its evolutionary significance. In a series of manipulative experiments the author quantified the effects of temperature, and time of day, as well as internal body temperature, on the colour of male K. tristis. The results suggest that male chameleon grasshoppers change colour primarily in response to temperature and that the rate of colour change varies considerably, with the change from black to turquoise occurring up to 10 times faster than the reverse. Body temperature changed quickly (within 10 min) in response to changes in ambient temperature, but colour change did not match this speed and thus colour is decoupled from internal temperature. This indicates that male colour change is driven primarily by ambient temperature but that their colour does not necessarily reflect current internal temperature. I propose several functional hypotheses for male colour change in K. tristis.  相似文献   

10.
Two growth experiments were conducted with juvenile red abalone, Haliotis rufescens and Japanese abalone, Haliotis discus hannai. The first experiment was set up to determine if nutrient levels used for co-culture of the Rhodophyte, Pacific dulse (Palmaria mollis) directly affected abalone growth. No significant differences (ANOVA; P=0.117) were found in growth of abalone cultured in either ambient seawater alone or seawater supplemented with different NaNO3 loads (1176, 1765, 2353, and 2942 μM day−1 NO3-N), NaH2PO4 (83.3 μM day−1 PO4), and a modified version of Guillard and Ryther's [Gran. Can. J. Microbiol. 8, (1962) 229] f medium containing Fe, Zn, Mn, Cu, Mo, and Co.The second experiment was designed to determine the effect of different nutrient levels on the nutritional value of P. mollis when fed to abalone. P. mollis was cultured with different NaNO3 loads (1176, 1765, 2353, and 2942 μM day−1 NO3-N) and NaH2PO4 (83.3 μM day−1 PO4) in the presence or absence of f medium trace metals (Fe, Zn, Mn, Cu, Mo, and Co). H. discus hannai showed the highest LGR and SGR when fed on P. mollis supplemented with nitrate loads ranging from 1176 to 2353 μM day−1 NO3-N. In contrast, H. rufescens showed the highest linear growth rate (LGR) when fed on P. mollis supplemented with higher nitrate loads of 2353 to 2942 μM day−1 NO3-N, while nitrate load had no significant effect on specific growth rate (SGR). Both abalone species grew better on P. mollis supplied with 0.75f+Zn (day−1) metal solution [Gran. Can. J. Microbiol. 8 (1962) 229] compared to those without trace metal additions, with H. discus hannai showing a further improvement in food conversion efficiencies (FCE).The present work shows that understanding and manipulating the culture environment of P. mollis can significantly affect growth, FCE, and daily food consumption (DFC) of H. discus hannai and H. rufescens.  相似文献   

11.
This study highlights the utility and limitations of multivariate procedures for the analysis and taxonomic interpretation of geographic variation within a complex species. Morphological data from herbarium specimens ofPersoonia mollis (Proteceae) were analyzed by two ordination procedures, multidimensional scaling (MDS) and canonical variate analysis (CVA). Support for the earlier recognition of nine infraspecific taxa was found. However, plots of canonical variate scores against latitute or longitude across parapatric subspecies boundaries revealed unexpected phenetic homogeneity within subspecies with sharp transitions between subspecies. The geographic variation in morphology withinP. mollis can be best described as a mosaic of nine recognisably distinct and internally homogeneous allopatric or parapatric taxa, where neighbouring taxa share surprisingly narrow zones of morphological transition at ecotones. The utility of these procedures was highlighted by the recovery of unexpected patterns of variation. However, questions of rank remain unresolved by phenetic analysis alone.  相似文献   

12.
To broaden the gene pool of domesticated commercial cultivars of narrow-leafed lupin (Lupinus angustifolius L.), wild accessions are used as parents in crossing in lupin breeding. Among the progenies from wild × domesticated (W × D) crosses, the soft-seediness gene mollis is the most difficult domestication gene to be selected by conventional breeding methods, where molecular marker-assisted selection (MAS) is highly desirable. MAS in plant breeding requires markers to be cost-effective and high-throughput, and be applicable to a wide range of crosses in a breeding program. In this study, representative plants from an F8 recombinant inbred line (RIL) population derived from a W × D cross, together with four cultivars and four wild types, were used in DNA fingerprinting by microsatellite-anchored fragment length polymorphisms (MFLP). Two co-dominant MFLP polymorphisms were identified as candidate markers linked to the mollis gene, and one of the candidate markers was selected and converted into a co-dominant, sequence-specific PCR marker. This marker, designated MoLi, showed a perfect match with phenotypes of seed coat permeability on a segregating population consisting of 115 F8 RILs, confirming the close genetic linkage to the mollis gene. Validation tests showed that the banding pattern of marker MoLi is consistent with all the 25 historical and current commercial cultivars released in Australia, and is consistent with mollis genotypes in 119 of the 125 accessions in the Australian L. angustifolius core collection. Marker MoLi provides a cost-effective way to select the mollis gene in a wide range of W × D crosses in lupin breeding.  相似文献   

13.
In Ethiopia, visceral leishmaniasis (VL) is an increasing public health concern. Recently, a new outbreak of VL claimed the lives of hundreds of Ethiopians. Mapping its distribution and the identification of the causative Leishmania species is important for proper use of resources and for control planning. The choice of appropriate typing technique is the key for determining the infecting species. Here we compared three deoxyribonucleic acid (DNA) based markers. We used, for the first time, cpbE and cpbF (cpbE/F) PCR-RFLP and demonstrated that it clearly differentiates Leishmania donovani from Leishmania infantum. The cpbE/F PCR-RFLP gave identical banding pattern for all L. donovani strains irrespective of their geographic origin. With the K26 (primers) PCR-RFLP, the L. donovani strains gave a banding pattern different from L. infantum and showed variation with geographic origin. The Ethiopian isolates typed as L. donovani by the PCR-RFLP of the cpbE/F (gene) and K26 (primers) showed two types of patterns with the T2/B4 (primers) PCR-RFLP; one group with L. infantum-like and the other L. donovani-like pattern. Phylogenetic analysis using cpbE/F sequences showed variation with geographic origin of strains and the African strains of L. donovani are more distantly related to L. infantum. Moreover, the Ethiopian isolates were seen to be closely related to the Sudanese, Kenyan and Indian strains. Thus, we recommend the use of more than one marker to study the population genetics of L. donovani complex.  相似文献   

14.
George W. Argus 《Brittonia》1984,36(3):328-329
In 1788 Walter described three species ofSalix inFlora Caroliniana. HisSalix pentandra is the same asS. caroliniana, andS. alpina andS. occidentalis are the same asS. tristis Aiton (1789).Salix alpina is a later homonym ofS. alpina Scopoli (1722), and must be rejected, butS. occidentalis is the earliest legitimate name forS. tristis and takes precedence.  相似文献   

15.
Chemical studies on Choisya arizonica, C. mollis, C. ternata, Esenbeckia hartmanii, Hesperethusa crenulata, Eremocitrus glauca, Triphasia trifolia, Coleonema album and Pamburus missionis are described with special reference to the limonoid bitter principles. The distribution of limonoids in the Rutaceae and especarlly the subfamily Aurantioideae is discussed. Two new coumarins, 7-isopentenyloxy-8-isopentenylcoumiain from Choisya arizonica and C. mollis and 2′,3′-dihydroxydihydrosuberosin from Coleonema album have been isolated and their structures determined.  相似文献   

16.
Habitats, phenology, food plants of adults and larvae, feeding, mating and egg-laying, the development of the larvae and pupae, and the natural enemies of Lixus paraplecticus L., L. elegantulus Boh., L. angustus Hbst., L. albomarginatus Boh., L. linnei Faust, and L. cylindrus F. were studied. Data on the geographic distribution, conservation, and economic importance of these species are given.  相似文献   

17.
Leymus mollis (Trin.) Pilger (NsNsXmXm, 2n = 28), a wild relative of common wheat, possesses many potentially valuable traits for wheat breeding, i.e., strong and short stems, long spikes with numerous spikelets, tolerance to drought and cold, and resistance to many fungal and bacterial diseases. In this study, we hybridized a wheat–L. mollis triple substitution line 05DM6 × Triticum aestivum L. cv. 7182 to obtain DM45, a single chromosome substitution line. Cytological studies demonstrated that DM45 had a chromosome karyotype of 2n = 42 = 21II. Genomic in situ hybridization analysis indicated that DM45 had a pair of Ns chromosomes from L. mollis. Analysis with DNA markers, i.e., two simple sequence repeats (Xgdm111 and Xgdm126) and two expressed sequence tag-sequence tagged sites (CD453004 and BE443796), showed that the wheat 1Ds chromosome were substituted with a pair of 1Ns chromosomes from L. mollis in DM45. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis suggested that DM45 possessed Ns genome-specific bands in the low and high molecular weight glutenin subunit regions, whereas it lacked one glutenin subunit translated from genes on chromosome 1D, thereby confirming that DM45 was a wheat–L. mollis 1Ns#1 (1D) disomic substitution line. Agronomic trait evaluations showed that DM45 was much improved in terms of the 1000-grain weight and the protein and glutenin contents of its seeds, as well as having more florets and spikelets compared with its relative, common wheat variety 7182. The substitution line DM45 could be used as a novel germplasm in wheat genetic and breeding programs.  相似文献   

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Eleven O-methylated derivatives of kaempferol, quercetin and quercetagetin were isolated from the dichloromethane leaf-wash of Balsamorhiza deltoidea. Four of these compounds represent new reports from either Balsamorhiza or Wyethia: 6-hydroxykaempferol 7-O-methyl ether, quercetin 3′,4′-O-dimethylether, quercetagetin 7-O-methyl ether, and quercetagetin 3,6,7-O-trimethyl ether. We also confirmed the presence of two isoflavones, santal and orobol 3′-O-methyl ether, in W. mollis. The 8-C-prenylated derivatives of naringenin, eriodictyol, and dihydroisorhamnetin were also identified as constituents of W. mollis. The vacuolar flavonoid fraction of Balsamorhiza deltoidea and Wyethia helenioides was shown to consist of simple mono and diglycosides of kaempferol and quercetin.  相似文献   

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