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1.
The present study is aimed to identify genetic variability between two species of Amaranthus viz., A. caudatus and A. hybridus subsp. cruentus, two economically important species, cultivated mainly for grain production. Karyomorphological studies in Amaranthus are scarce, probably due to higher number of small sized chromosomes. Karyomorphological studies were conducted using mitotic squash preparation of young healthy root tips. Karyological parameters and karyotypic formula were established using various software programs and tabulated the karyomorphometric and asymmetry indices viz., Disparity index, Variation coefficient, Total forma percentage, Karyotype asymmetry index, Syi index, Rec index, Interchromosomal and Intrachromosomal asymmetry index and Degree of asymmetry of karyotypes. The mitotic chromosome number observed for A. caudatus was 2n = 32 with a gametic number n = 16 and A. hybridus subsp. cruentus was 2n = 34 with a gametic number n = 17. In A. caudatus the chromosome length during somatic metaphase ranged from 0.8698 to 1.7722 μm with a total length of 39.1412 μm. In A. hybridus subsp. cruentus the length of chromosome ranged from 0.7756 to 1.9421 μm with a total length of 44.9922 μm. Various karyomorphometry and asymmetry indices analyzed revealed the extend of interspecific variation and their evolutionary status.  相似文献   

2.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

3.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

4.
Arbutoid mycorrhizae were synthesized in vitro between Arbutus unedo L. and two isolates of Lactarius deliciosus. The fungal isolates were obtained from sporocarps collected under Pinus sylvestris and in a mixed forest stand of Quercus suber and Pinus pinea. Synthesis tubes filled with a mixture of sterilized peat, vermiculite, and perlite imbibed with nutrient solution were used. Two inoculation methods using solid and liquid media were tested. Shoots from an adult selected clone of A. unedo were used after in vitro rooting by auxin dipping. After 3 months of shoots transfer to the substrate, the root systems were examined for arbutoid mycorrhizae formation and later on ex vitro conditions, 9 months after acclimatization. The inoculum treatment with liquid medium improved the mycorrhizal development for both isolates, in vitro. Sterilized substrate for plant acclimatization increased the mycorrhizal development. The arbutoid mycorrhizae were observed in vitro as well as 9 months after acclimatization. Standard arbutoid mycorrhiza features were observed: pale yellow mantle, typical cruciform appearance, Hartig net (HN), and intracellular hyphal complexes, both confined to the epidermis. L. deliciosus mycorrhizae synthetized in vitro persisted 9 months after plant acclimatization. Morphological observations were confirmed by molecular techniques.  相似文献   

5.
This paper reports on the successful Agrobacterium-mediated transformation of oat, and on some factors influencing this process. In the first step of the experiments, three cultivars, two types of explant, and three combinations of strain/vectors, which were successfully used for transformation of other cereals were tested. Transgenic plants were obtained from the immature embryos of cvs. Bajka, Slawko and Akt and from leaf base explants of cv. Bajka after transformation with A. thumefaciens strain LBA4404(pTOK233). The highest transformation rate (12.3%) was obtained for immature embryos of cv. Bajka. About 79% of the selected plants proved to be transgenic; however, only 14.3% of the T0 plants and 27.5% of the T1 showed GUS expression. Cell competence of both types of explant differed in terms of their transformation ability and transgene expression. The next step of the study was to test the suitability for oat transformation of the pGreen binary vector combined with different selection cassettes: nptII or bar under the nos or 35S promoter. Transgenic plants were selected in combinations transformed with nos::nptII, 35S::nptII and nos::bar. The highest transformation efficiency (5.3%) was obtained for cv. Akt transformed with nos::nptII. A detailed analysis of the T0 plants selected from a given callus line and their progeny revealed that they were the mixture of transgenic, chimeric-transgenic and non-transgenic individuals. Southern blot analysis of T0 and T1 showed simple integration pattern with the low copy number of the introduced transgenes.  相似文献   

6.
Cabbage (Brassica oleracea var. capitata L.) is one of the most popular cultivated vegetables worldwide. Cabbage has rich phenotypic diversity, including plant height, head shape, head color, leaf shape and leaf color. Leaf color plays an important role in cabbage growth and development. At present, there are few reports on fine mapping of leaf color mutants in B. oleracea. In this study, a naturally occurring yellow-green leaf cabbage mutant (YL-1), derived from the self-pollinated progenies of the hybrid ‘Hosom’, was used for inheritance analysis and gene mapping. Segregation populations including F2 and BC1 were generated from the cross of two inbred lines, YL-1 and 01–20. Genetic analysis with the F2 and BC1 populations demonstrated that the yellow-green leaf color was controlled by a single recessive nuclear gene, ygl-1. Insertion–deletion (InDel) markers, designed based on the parental re-sequencing data, were used for the preliminary mapping with BSA (bulked segregant analysis) method. A genetic map constructed with 15 InDels indicated that ygl-1 was located on chromosome C01. The ygl-1 gene is flanked by InDel markers ID2 and M8, with genetic distances of 0.4 cM and 0.35 cM, respectively. The interval distance between two markers is 167 kb. Thus, it enables us to locate the ygl-1 gene for the first time in B. oleracea. This study lays the foundation for candidate gene prediction and ygl-1gene cloning.  相似文献   

7.
A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.  相似文献   

8.
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.  相似文献   

9.
Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae.  相似文献   

10.
Tuber huidongense and T. liyuanum are common commercial white truffles in China that belong to the Rufum and Puberulum groups of the genus Tuber, respectively. Their mycorrhizae were successfully synthesized with two native trees—Castanea mollissima and Pinus armandii—under greenhouse conditions. The identities of the mycorrhizae were confirmed through internal transcribed spacer (ITS) sequence analyses, and their morphological characteristics were described. All of the obtained mycorrhizae have an interlocking pseudoparenchymatous mantle, which is a typical feature of truffle mycorrhizae. The mycorrhizae of T. huidongense on the two trees have hyaline branched emanating hyphae, similar to the documented mycorrhizae of the Rufum group. The unramified, spiky, and hyaline cystidia on the mycorrhizae of T. liyuanum with both C. mollissima and P. armandii further confirmed that this characteristic is constant for the mycorrhizae of the Puberulum group. The successful mycorrhizal syntheses on the two nut-producing trees will be of economic importance in the cultivation of the two truffles.  相似文献   

11.
Seol E  Jung Y  Lee J  Cho C  Kim T  Rhee Y  Lee S 《Plant cell reports》2008,27(7):1197-1206
Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.  相似文献   

12.
Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.  相似文献   

13.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

14.
Amaranth is a new and promising crop for the Russian climate, notable for its well-balanced amino acid composition. Yield increase using the methods of genetic engineering is a challenging task. We generated transgenic plants of amaranth with expression of the Arabidopsis thaliana ARGOS-LIKE gene under the control of the dahlia mosaic virus promoter. We achieved 1.4% transformation effectiveness. In comparison with wild-type amaranth, we observed a 21% increase in stem length, 79% increase in leaf length, and 190% increase in fresh weight of transgenic plants. It was shown that ARGOS-LIKE gene of A. thaliana along with the dahlia mosaic virus promoter can be used to increase primarily the green weight of shoot and leaf size of amaranth.  相似文献   

15.
Leaves of Solanum virginianum plants were used for protoplast isolation. To support cell wall formation and cell division, protoplasts were cultured in thin alginate layers floated in liquid medium. When protoplasts were plated at a density of 1.0 × 106/ml in Kao and Michyaluk (KMp8) medium supplemented with 0.5 mg/l zeatin, 1.0 mg/l 2,4-dichlorophenoxyacetic acid, and 1.0 mg/l α-naphthaleneacetic acid, 42.3% of the dividing cells developed microcalli in 3–4 weeks. Shoot formation via organogenesis of protoplast-derived calli was achieved for 28% of calli transferred to solidified KMp8 medium supplemented with 2.0 g/l zeatin and 0.1 mg/l 3-indol acetic acid in about 2 weeks. Further shoot development was observed in Murashige and Skoog (MS) medium without growth regulators and roots were induced after transfer to MS medium containing 1.0 mg/l 3-indol butyric acid. Regenerated plants have normal morphology.  相似文献   

16.
The effects of Chinese cabbage (Brassica rapa subsp. pekinensis) carrying cry1AC derived from Bacillus thuringiensis (Bt) on leaf bacterial community were examined by analyzing the horizontal transfer of trans-gene fragments from plants to bacteria. The effect of plant pathogenic bacteria on the gene transfer was also examined using Pseudomonas syringae pathovar. maculicola. The frequency of hygromycin-resistant bacteria did not alter in Bt leaves, though slight increase was observed in Pseudomonas-infected Bt leaves with no statistical significance. The analysis of bacterial community profiles using the denaturing gradient gel electrophoresis (DGGE) fingerprinting indicated that there were slight differences between Bt and control Chinese cabbage, and also that infected tissues were dominated by P. syringae pv. maculicola. However, the cultured bacterial pools were not found to contain any transgene fragments. Thus, no direct evidence of immediate gene transfer from plant to bacteria or acquisition of hygromycin resistance could be observed. Still, long-term monitoring on the possibility of gene transfer is necessary to correctly assess the environmental effects of the Bt crop on bacteria.  相似文献   

17.
This study examines the interactions that occur between Saccharomyces cerevisiae and Oenococcus oeni strains during the process of winemaking. Various yeast/bacteria pairs were studied by applying a sequential fermentation strategy which simulated the natural winemaking process. First, four yeast strains were tested in the presence of one bacterial strain leading to the inhibition of the bacterial component. The extent of inhibition varied widely from one pair to another and closely depended on the specific yeast strain chosen. Inhibition was correlated to weak bacterial growth rather than a reduction in the bacterial malolactic activity. Three of the four yeast strains were then grown with another bacteria strain. Contrary to the first results, this led to the bacterial stimulation, thus highlighting the importance of the bacteria strain. The biochemical profile of the four yeast fermented media exhibited slight variations in ethanol, SO(2) and fatty acids produced as well as assimilable consumed nitrogen. These parameters were not the only factors responsible for the malolactic fermentation inhibition observed with the first bacteria strain. The stimulation of the second has not been reported before in such conditions and remains unexplained.  相似文献   

18.
Summary Shoot tips and leaves excised from in vitro shoot cultures of Salvia nemorosa were evaluated for their organogenic capacity under in vitro conditions. The best shoot proliferation from shoot tips was obtained on Murashige and Skoog (MS) medium supplemented with 8.9 μM 6-benzylaminopurine (BA) and 2.9 μM indole-3-acetic acid (IAA). Leaf lamina and petiole explants formed shoots through organogenesis via callus stage and/or directly from explant tissue. The highest values for shoot regeneration were obtained with 0.9 μM BA and 2.9 μM IAA for lamina explants. No shoot organogenesis was obtained on leaf explants cultured on MS medium supplemented with α-naphthaleneacetic acid (NAA). The regenerated shoots rooted the best on MS medium containing 0.6 μM IAA or 0.5 μM NAA. In vitro-propagated plants were transferred to soil with a survival rate of 85% after 3 mo.  相似文献   

19.
20.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

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