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1.
To overexpress the chitosanase gene (csn) in F. solani, a vector based on pCAMBIA 1300 was constructed. The csn gene, which is under control of the Aspergillus nidulans gpdA promoter and A. nidulans trpC terminator, was introduced back into the F. solani genome by Agrobacterium tumefaciens-mediated transformation, and the herbicide-resistance gene bar from Streptomyces hygroscopicus was used as the selection marker. Transformants which showed a significant increase in chitosanase production (~2.1-fold than control) were obtained. Southern blot analysis indicated that most transformants had a single-copy T-DNA integration.  相似文献   

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Small heat shock proteins (sHSPs) act as molecular chaperones and are widely distributed in all kinds of organisms. Comparative analysis revealed that an orthologous shsp was present during insect evolution. Here, hsp21.8b, one insect orthologous shsp, had been identified in Tribolium castaneum. Quantitative real‐time PCR illustrated that Tchsp21.8b was expressed in all developmental stages, along with the lowest expression at early embryonic stage and relative high expression at other stages especially in late eggs and late pupae. In the adult period, Tchsp21.8b exhibited the highest expression level in central nervous system and followed in elytron, epidermis, ovary and fat body. Moreover, it was upregulated 3.39‐fold in response to enhanced heat stress (45°C) for 4 hr but not to cold stress (4°C) and was upregulated by 1.73‐ to 1.94‐fold under ultraviolet (UV) exposure during 4–6 hr. It was also downregulated by 20.8%–41.8% under starvation in 3 days and had a “down‐up‐down” trend under the pathogen stresses. Larval RNA interference of Tchsp21.8b caused 40.6% insects mortality and reduced the oviposition amount by 66.0% and only 21.0% of the ds‐Tchsp21.8b eggs could hatch into larvae. These results suggested that as an orthologous shsp, Tchsp21.8b not only plays important roles in the growth, development and fecundity of T. castaneum but with the competence to resist the environment stresses, although the response is relatively weak compared to other hsps. Results from this study also uncovered the functions of the orthologous shsp in the development and anti‐stresses ability of T. castanuem. It provided more scientific evidence for revealing the physiological mechanisms of shsps of the insects and enhanced the capabilities to control different pests.  相似文献   

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Aspergillus section Nigri strains Aspergillus aculeatus Ege-K 258, A. foeditus var. pallidus Ege-K156, A. niger Ege-K 4 and A. tubingensis Ege-K 265 were used to treat olive mill wastewater (OMW) in an investigation aimed at exploring their dephenolisation and decolourisation ability and, consequently, the economic feasibility of using any or all of these strains in a pre-treatment step in the processing of OMW. Of these strains A. tubingensis Ege-K 265 resulted in an 80% decolourisation of twofold-diluted OMW and a 30% decolourisation of undiluted OMW; in addition, it was able to remove approximately 30% of all phenolic compounds in both twofold-diluted and undiluted OMW. We conclude that A. tubingensis Ege-K 265 could be effectively used in the pre-treatment step of a combined aerobic-anaerobic process to solve the environmental problems caused by OMW in Mediterranean countries.  相似文献   

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High-frequencyin vitro flowering is reported here fromin vitro regenerated shoots ofin vitro-raised seedlings of rare and endemicCeropegia lawii, Ceropegia maccannii, Ceropegia oculata, andCeropegia sahyadrica, as well as the widely distributedCeropegia bulbosa var.bulbosa andCeropegia hirsuta. In our first set of experiments, the MS medium contained 87 mM sucrose and was supplemented with varying concentrations of BAP (4.4 to 26.6 μM). For the second set of trials, varying concentrations of sucrose (87 to 233 mM) were tested in MS media containing a constant 4.4 p.M BAP. Sub-cultured apical as well as axillary buds flowered with similar frequencies after 30 d of incubation. For all six species, the highest percentage of flowering shoots was obtained with either 26.6 μM BAP or 175 mM sucrose. Although smaller in size, theirin vitro flowers were morphologically comparable within wVo-derived flowers. Variations among species were noted for the number of flower buds per shoot and the percentage of flower formation. Because all six species showed similar responses in both experiments, we can suggest that this protocol is applicable across the wide range ofCeropegia species.  相似文献   

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ITS sequences determined for 53 Erysiphe specimens on Syringa and Ligustrum collected in Europe, East Asia, and North and South America were divided into two ITS groups, S and K types. Phylogenetic analysis showed that these two ITS types do not share a common ancestor and form separate clades. The K type on Ligustrum was identified as Erysiphe ligustri based on the three-dimensional branching pattern of appendages. Morphological observations showed that there are some morphological differences—pigmentation of appendages and number of ascospores per ascus—between the S and K types on Syringa. Based on these morphological observations, the S and K types on Syringa were identified as E. syringae and E. syringae-japonicae, respectively. The recent abundant production of chasmothecia by lilac powdery mildew in Europe was caused by E. syringae-japonicae introduced from East Asia. DNA sequence analyses of the rDNA ITS region and the 28S rDNA, tub2, CYP51, and Chs1 genes did not support an interspecific hybrid origin for E. syringae-japonicae. Haplotype analysis suggested that E. syringae originated in North America and independently migrated to East Asia and Europe/South America.  相似文献   

9.
In vitro regeneration of black nightshade (Solanum nigrum L.) plants was achieved through callus-mediated shoot organogenesis followed by 30 d indoor ex vitro adaptation to nutritional stress under environmental ambience and thereafter 6-d outdoor acclimatization in pots prior to field establishment. Relevant physiological parameters including pigment content, chlorophyll a fluorescence, net photosynthetic rate (P N), transpiration rate (E), and stomatal conductance (g s) of in vitro-regenerated plants were investigated during the course of ex vitro adaptation. During the first 4 d of indoor transplantation to potting substrate, there was a marginal reduction in the leaf chlorophyll and carotenoid contents but P N and E were strongly reduced. The stomatal conductance and E/P N ratio were significantly higher in plants up to 20 d of indoor adaptation than those of comparable age grown naturally from seeds. The shape of the OJIP fluorescence transient varied significantly with acclimatization, and the maximum change was observed at 2.0 ms. The 2.0 ms variable fluorescence (V j), 30 ms relative fluorescence (M 0), photon trapping probability (TR0/Abs), and photosystem II (PSII) trapping rate (TR0/RC) showed initial disturbance and subsequent stabilization during 30 d of indoor acclimatization. Energy dissipation (DI0/RC) and electron transport probability (ET0/TR0) showed an initial phase of increase during the 4 d after plants were transplanted outdoors. During the 6-d outdoor acclimatization after transfer of plants to soil, no significant change in total chlorophylls and carotenoids, E, and g s were observed, but P N improved after reduction on the first d. The OJIP-derived parameters experienced change on the first d but were stabilized quickly thereafter. There was no significant difference between outdoor acclimatized plants and those of the seed-grown plants of comparable age with respect to photosynthetic and fluorescence parameters. Direct transfer of plants without indoor acclimatization, however, showed a completely different trend with respect to P N, E, and OJIP fluorescence transients. The bearing of this study on optimizing micropropagation is discussed.  相似文献   

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The life cycle and developmental stages of Aylax hypecoi (Trotter, 1913, Hymenoptera: Cynipidae: Aylacini) were studied in detail. Aylax hypecoi is known to induce galls in fruits of two Hypecoum species — H. imberbe and H. geslini (Papaveraceae) and the larva develops in host plant fruits. The morphology and development of egg, larva and pupa were investigated, which has previously not been done. The shape and size of terminal-instar larvae and associated galls are sex-specific. Overwintering stage, adult emergence and flying periods, and egg productivity were studied also.  相似文献   

13.
Survey of seven strains determined as Septonema ochraceum (Dothideomycetes, inc. sed.) isolated from pine litter or obtained from public collections revealed three new species, Fusicladium cordae, F. sicilianum (Venturiaceae), Cladophialophora matsushimae (Herpotrichiellaceae) and a cryptic species morphologically identical to Devriesia americana (Teratosphaeriaceae), but phylogenetically distinct. Morphological survey and phylogenetic analysis using nucleotide sequence data from the nuclear ribosomal subunit genes indicate a close relationship within three species colonising pine litter needles, F. cordae, F. pini and F. ramoconidii. F. sicilianum is most related to F. rhodense. C. matsushimae represents a species belonging to one of the lineages of the polyphyletic genus Cladophialophora. None of the strains observed can be classified morphologically as S. ochraceum, of which the type material does not exist.  相似文献   

14.
The acetylcholinesterase inhibition by enantiomers of exo‐ and endo‐2‐norbornyl‐Nn‐butylcarbamates shows high stereoselelectivity. For the acetylcholinesterase inhibitions by (R)‐(+)‐ and (S)‐(?)‐exo‐2‐norbornyl‐Nn‐butylcarbamates, the R‐enantiomer is more potent than the S‐enantiomer. But, for the acetylcholinesterase inhibitions by (R)‐(+)‐ and (S)‐(?)‐endo‐2‐norbornyl‐Nn‐butylcarbamates, the S‐enantiomer is more potent than the R‐enantiomer. Optically pure (R)‐(+)‐exo‐, (S)‐(?)‐exo‐, (R)‐(+)‐endo‐, and (S)‐(?)‐endo‐2‐norbornyl‐Nn‐butylcarbamates are synthesized from condensations of optically pure (R)‐(+)‐exo‐, (S)‐(?)‐exo‐, (R)‐(+)‐endo‐, and (S)‐(?)‐endo‐2‐norborneols with n‐butyl isocyanate, respectively. Optically pure norborneols are obtained from kinetic resolutions of their racemic esters by lipase catalysis in organic solvent. Chirality 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

15.
Previous studies on the fourth inversion of the t complex, In17(4), suggest that loci near the center of this inversion have been subjected to segmental recombination during the past 1–2 million years. We have used a combination of PCR-based restriction site (PBR) analysis and DNA sequencing to perform a high-resolution analysis of a 2-million base pair (Mbp) segment in the middle of In17(4). We examined 21 restriction sites that are polymorphic between t haplotypes and their wild-type homologs, over nine distinct loci. In addition, we examined several other polymorphic sites through DNA sequence analysis of two of these nine loci. We analyzed several haplotypes in this way, including the “complete” t haplotypes t w2 , t 0 , t w32 , t w71 , and t w75 . We show that only t w32 is a true “complete” t haplotype; the remaining four t haplotypes have segments of wild-type DNA ranging from less than 100 bp to 2 Mbp. The sizes of these wild-type DNA segments are consistent with their being generated by gene-conversion events. The 2-Mbp segment is located in a region that may contain the t-complex distorter gene Tcd2. One of the nine loci examined in this study is Fgd2, a gene that has been proposed to encode Tcd2. Sequencing and PBR data show that at least a portion of the Fgd2 gene has been converted to the wild-type within t w71 and t w75 mice.  相似文献   

16.
Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this disease.  相似文献   

17.
Micromorphological differences in leaves and pollen between two American (Fraxinus americana L., F. pennsylvanica Marshall) and two European (F. angustifolia Vahl, F. excelsior L.) ash species were studied using scanning electron microscope. The types, dimensions and distribution of characteristic trichomes were established and measured. Capitate hairs on the leaves had the same shape in all researched ash species. Acicular hairs were regularly present in two American ash species, but very rarely in the glabrous phase of F. angustifolia and F. excelsior. Only F. americana had coronulate abaxial surface of leaves. Pollen of F. angustifolia and F. excelsior had 3 (tricolpate) apertures, and F. americana and F. pennsylvanica 4 (stephanocolpate) apertures. Based on the appearance of the reticulum it’s possible to clearly distinguish all four species. F. angustifolia and F. pennsylvanica had muri with transversal ridges and seldom granules. Muri of F. excelsior and F. americana had slightly visible transversal ridges, and because of that noticeable granules.  相似文献   

18.
Genes of CLE (CLAVATA3/ESR-related) family encode peptide ligands that regulate plant development in response to external stimuli such as rhizobial infection and the nitrate application as well as various internal stimuli. To investigate whether LjCLE gene(s) may involve in plant response to inorganic phosphate (Pi), we analyzed Pi responses of 39 LjCLE genes in hydroponically grown Lotus japonicus plants (ecotype Miyakojima ‘MG-20’). Two LjCLE genes, LjCLE19 and 20, were up-regulated specifically and greatly in roots of L. japonicus by Pi addition to the hydroponic solution. When the external Pi level increased, expressions of LjCLE19 and 20 increased before the increase in the Pi content in plants. On the other hand, when the external Pi level decreased, the Pi content in plants decreased first, then expression levels of LjCLE19 and 20 decreased. Based on our results, we discuss the relationship between LjCLE19 and 20 and the tissue Pi levels in plants. This is the first report showing induction of specific CLE genes by phosphate.  相似文献   

19.
The test for somatic mutagenesis and recombination in Drosophila is one of the widely used approaches for determination of possible carcinogenic effects of chemical compounds. The use of heterozygotes for mutant tumor suppressor gene wts enables more direct evaluation of the blastomogenic effects of chemical compounds, by tumor formation in the adult flies. This study presents evaluation of the SMART effectiveness upon the use of Drosophila heterozygotes for the wts P4 gene, first included into the test system. The increase of the test resolution capacity compared to the literature data for the wts P2 allele was observed. Using wts P4 heterozygotes, a total of 20 carcinogenic compounds, and their slightly carcinogenic and non-carcinogenic analogs were tested. Specificity of the method was about 100%, and sensitivity depended on the type of the agent tested. The latter was absolute for the direct action carcinogens, with respect to carcinogens, requiring the metabolic activation. The sensitivity was elective and was limited by the presence of the enzymes capable of activating of these compounds. To increase the test sensitivity, the RNA interference-mediated silencing of the Drosophila p53 functional activity was successfully applied. Moreover, the frequency of wts tumor induction considerably increased both in spontaneous and induced mutagenesis conditions.  相似文献   

20.
The CONSTANS (CO) gene is a key regulator of the response to photoperiod in the model plant Arabidopsis thaliana, and its homologues are present in many plant species. We describe here the isolation of the CO homologue for zinc finger protein gene GmCOL10 (Glycine max CONSTANS-Like 10) from the soybean cultivar Kennong18. Sequence comparisons showed that the closest A. thaliana gene to GmCOL10 is COL5. The expression of GmCOL10 was regulated in a circadian manner, especially under short-day conditions. The expression of GmCOL10 was concentrated in vegetative organs, and in particular in the unifoliolates and cotyledons. An analysis of subcellular localization found GmCOL10 in the nucleus. Our data suggested that GmCOL10 was not related to the photoperiodic pathway of floral transition as Arabidopsis CO does.  相似文献   

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