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1.
红树林内生真菌1893是从中国南海秋茄(Kandelia candel)上分离的一株内生真菌,在液体发酵条件下能够产生包括1893A和1893B在内的多种新物质。为了正确的鉴定该菌株并为进一步的工业应用做准备,本文结合形态学和分子学两方面对它进行了鉴定,首先,在纯培养条件下,将它和具有以下形态特征的相似菌株进行比较:产生受精丝或像受精丝一样的菌丝,这些菌丝又和像雄器一样的菌丝发生明显的融合现象;环状产囊体与大量菌丝缠绕形成菌核前体。进一步通过该菌株在寄主秋茄和非寄主芒果叶子上的培养性状与其它相似真菌比较,结果将该菌株归于拟茎点霉属(Phomopsis)。其次,在ITS序列水平上,将它和具有形态学或生态学相似性的拟茎点霉进行系统发育分析。最后,综合形态学和分子学,红树林内生真菌1893被定为Diaporthe phaseolorum var.sojae,本文是首次报道Diaporthe phaseolorum var.sojae做为内生真菌寄生于秋茄。图5参43。  相似文献   

2.
A mangrove endophytic fungus 1403 isolated from the South China Sea Coast, which is able to produce griseofulvin and anthracenediones under submerged fermentation, was compared with Fusarium genus with the similar morphological characters such as elongated, microconidium-producing conidiophores, ovoid microconidia and straight to slightly curved macroconidia. It was found that the fungus 1403 resembles pathogenic F. verticillioides (teleomophy Gibberella moniliforme) in the production of false head or chains and abundant microconidia on the aerial mycelium, but different in the occasional formation of polyphialides with relatively long as well as short monophialides, in its typical coiled hyphae and mycelia fusion. Through maximum Parsimony and Bayesian analyses, the fungus 1403 was further compared with some similar Fusarium species. The results indicated that this endophyte was identified as Fusarium proliferatum based on the analyses of partial 18S and 28S rDNA genes, ITS region, and EF-1α gene. Foundation project: This research was supported partly by the Guangzhou Natural Science Foundation (Grant No. 2007Z3-EO581), the Guangdong Provincial Natural Science Foundation (Grant No. 2007A0200300001-7; 05003268), the Chinese High-Tech 863 Project (Grant No. 2006AA09Z422), and the National Natural Science Foundation of China (Grant No. 20572136)  相似文献   

3.
The genetic diversity of the mangrove tree speciesKandelia candel andBruguiera gymnorrhiza in the Southwest Islands of Japan was investigated. These islands are located at the periphery of the distribution area of the two species, and their populations are relatively small. Allozyme analyses of 17 loci inK. candel and 13 loci inB. gynmorrhiza revealed very little genetic variation in both species. At the species level, the proportion of polymorphic loci was 4.2%, the average effective number of alleles per locus was 1.02, and the average expected heterozygosity was 0.012 inK. candel. The corresponding figures forB. gymnorrhiza were 9.0%, 1.06 and 0.035, respectively. However, the coefficients of genetic differentiation among the populations were high (G ST=0.165 forK. candel and 0.253 forB. gymnorrhiza). The genetic variation and habitat area ofK. candel on Amami Island is greater than on the islands Okinawa and Iriomote. The genetic variation and habitat area ofB. gymnorrhiza is greater on Iriomote Island than on the islands Okinawa and Amami. The level of genetic variation in both of the species might be related to their population sizes.  相似文献   

4.
In order to investigate flower development and female abortion during sex differentiation of Xanthoceras sorbifolia, anatomical observations and comparative study on differential proteins were carried out in different developmental stages of two types of flowers of this species. It was found that the selective abortion happened in male flower before the formation of megasporocyte. Special proteins related to the female abortion were found through 2-dimensional electrophoretic analysis. Protein A1 (14.2 kD) only existed in florescence of male flower, while B1 (13.7 kD) and B2 (18.2 kD) disappeared in that stage of male flower. They were all considered to be relative to pistil abortion of Xanthoceras sorbifolia. [Supported by the National Natural Science Foundation of China (Grant No.30070613) and Graduate Cultivation Foundation of Beijing Forestry University (Grant No.02jj001)]  相似文献   

5.
PtLFY, a LEAFY (LFY) gene, was cloned from Populus tomentosa (LM50) by PCR. Sequencing analysis indicated that PtLFY was 2 629 bp long, composed of three exons and two introns and encoded 378 amino acids. The splice donor sites and the splice acceptor sites were in identical positions to the LFY and its homologues. The amino acid sequence inferred was 68%-99% homologous to those of LFY and its homologues by blast analysis in GenBank. The Southern blot analysis indicated that there was a single copy of the PtLFY gene in genomic DNA of male and female P. tomentosa (LM50 and 5082). The pBI121-Ptalfy (reverse)-intron-Ptlfy-GUS-nos was constructed using RNA interference (RNAi) technique and verified by PCR and digestion identification and transformed into tobacco. Some transgenic tobacco plants were obtained by PCR and PCR-Southern identification. The growth was generally repressed in transgenic tobacco plants compared with wild-type ones and some phenotypic differences were observed. [Supported by the National Natural Science Foundation of China (Grant No. 30371175) and Postdoctoral Foundation of China (Grant No. 2002032041)]  相似文献   

6.
Total genomic DNA was extracted from leaves of Ginkgo biloba L. by the method of hot CTAB. After determining quantification of DNA sample by microclorimetric spectrophotography, Arabidopsis-type telomere primer and Sau3A I cassette primer were used to isolate telomere-associated sequences from G. biloba L. by the method of cassette-ligation-mediated polymerase chain reaction (PCR). Using this method, two telomere-associated sequences, TAS1 and TAS2, were isolated. The authors preformed Southern hybridization ofEcoR I-treated G. biloba genomic DNA with each clone. The hybridization pattern showed that the clones obtained were derived from G. biloba genomic DNA. There are the Arabidopsis-type TTTAGG tandem repeats in telomeres of G.biloba.  相似文献   

7.
Podophyllotoxin is isolated mainly from the rhizomes of Podophyllum plants, and serves as the main precursor for synthesis of anticancer drugs, such as VP-16 and VM-26. VP-16 and VM-26 are used for curing lung cancer, testicular cancer, neuroblastoma, hepatoma and other tumors. However, these plants are all near-extinction species due to over-collection and their own biological characteristics. The chemical synthesis of podophyllotoxin is so complicated that its price is unbelievably high. This paper discusses the current status of the biosynthetic pathway of podophyllotoxin and that of the podophyllotoxin production using several biotechnological approaches such as plant organ cultures, plant cell cultures with both flasks and bioreactors, hairy root cultures, bioconversions and metabolic regulations. [Supported by the Natural Science Foundation of Tibet (Grant No. 2002-66)]  相似文献   

8.
Mangroves play an important role in coastal ecosystems. In this work, Cladosporium spp were isolated from a natural mangrove environment in Zhanjiang Bay, Guangdong Province, China. Ninety‐one isolates were obtained and identified as Cladosporium cladosporioides, C. colocasiae, C. oxysporum, C. perangustum, C. sphaerospermum, C. tenuissimum and C. uredinicola. Forty‐two isolates were selected and tested for pathogenicity towards mangroves. The results showed that pathogenic isolates were found on Avicennia marina, Kandelia candel and Rhizophora stylosa with prevalence of 93.40%, 83.52% and 7.41%, respectively. This indicated that A. marina and K. candel were more vulnerable to Cladosporium ssp. than R. stylosa. Among the seven species, C. colocasiae had the strongest pathogenic effect towards A. marina and K. candel with a prevalence of 100.00%. The rest of the seven species also showed pathogenic effects on the same plants. These results provided valuable insights into the effect of various pathogens on mangroves.  相似文献   

9.
To analyze the function of PtAP3, an APETALA3 (AP3) homologue gene isolated from Populus tomentosa Carr., the full length sequence (1797 bp) and a fragment (870 bp) of PtAP3 were fused to a CaMV 35S promoter of pBI121 to generate the sense and antisense constructs of PtAP3. These constructs were transformed into tobacco by Agrobacterium infection of leaf disks and selection on kanamycin medium. Some sense and antisense transgenic tobacco plants were obtained by PCR and Southern blot analysis. Great phenotypic differences in transgenic tobacco plants were observed. Almost all of sense PtAP3 to transgenic tobaccos showed a higher growth rate than those of antisense transformants and a few developed pregnancy earlier than wild type seedlings and antisense transformants under the same conditions.  相似文献   

10.
A 1207 bp cDNA fragment (PsG6PDH) was amplified by RT-PCR from cold-induced total RNA of the freezing-tolerant P. Suaveolens, using primers based on the highly conserved region of published plant glucose-6-phosphate dehydrogenase (G6PDH) genes. The sequence analysis showed that PsG6PDH coding region had 1 101 bp and encoded 367 predicted amino acid residues. Moreover, the nucleotide sequence of PsG6PDH showed 83%, 82%, 79%, 79% and 78% identity, and the derived amino acid sequence shared 44.2%, 44.7%, 42.0%, 40.5% and 43.9% identity with those of the Solanum tuberosum, Nicotiana tabacum, Triticum aestivum, Oryza sativa and Arabidopsis thaliana, respectively. The results show that PsG6PDH is a new member of G6PDH gene family and belongs to the cytosolic G6PDH gene. This is the first report on cloning of the G6PDH gene from woody plants.  相似文献   

11.
Fallen wood decomposition rate ofPinus koraiensis andTilia amurensis in broadleaved Korean pine forest was studied in this paper. The result showed that decomposition rate of fallen wood was different from that of little diameter wood and coarse woody debris for the same tree species. Fallen wood decomposition was generally rotten from outside to inside. And decomposition speed of fallen woods was different according to tree species and site, and it was also related to diameter of fallen woods. Decomposition depth ofTilia amurensis fallen wood for 17 years was 14 cm, but that ofPinus koraiensis in the same condition was less than 7 cm.Tilia amurensis was decomposed faster thanPinus koraiensis. For same tree species, if the diameter was small, the decomposition speed was quick. This project was supported by Natural Science Foundation of China (No. 39670144) and funded by the Opened Research Station of Changhai Mountain Forest Ecosystem, Chinese Academy of Sciences. (Responsible editor: Zhu Hong)  相似文献   

12.
Endophytic fungi were isolated from healthy leaves of the evergreen oak Quercus acuta on Mt Takao in eastern Honshu and on Mt Osuzu in Kyushu, Japan, to study the effect of altitude on endophyte assemblages. Phomopsis sp. 1, Discula sp. and an unidentified species (QA-b) were isolated most frequently. Comparisons of the nucleotide sequence of the rDNA ITS regions of QA-b revealed a close match with species of Tubakia. On Mt Takao, Phomopsis sp. 1 and QA-b were isolated frequently, whereas on Mt Osuzu, Discula sp. and QA-b were dominant. The isolation frequency of QA-b decreased as altitude increased, whereas the isolation frequencies of Phomopsis sp. 1 and Discula sp. increased with altitude. In vitro, QA-b did not grow at temperatures <15°C whereas Phomopsis sp. 1 and Discula sp. still grew at 5°C. These results suggest that Phomopsis sp. 1 and Discula sp. are better adapted to lower temperatures and consequently to higher altitude than QA-b.  相似文献   

13.
The population dynamic tendency ofAdenophora lobophylla Hong as an endangered species andAdenophora potaninii Korsh as widespread species, has been predicted by the Leslie matrix. And the comparison and analysis on the age structures between two species have been carried out in this paper. The results demonstrate theA. lobophylla populations which have the reasonable age structures perform slowly negative or positive increment at altitude 2300–3400 m. Especially. below altitude 2700 m. there are many populations performing seriously declining tendency. Contrary.A potaninii populations could adapt to environment perfectly at the corresponding condition without finding the population which performs the seriously declining tendency. The differences in developing tendency of population between the two species demonstrate thatA. lobophylla populations have the weaker ability to adapt to the external unfavorable conditions. The project was supported by Chinese Natural Science Foundation. (No. 3939150) The experiment carried out at the Botanical Department of University Federal Sao Carols in Brazil (Responsible Editor: Zhu Hong)  相似文献   

14.
Antifreeze proteins (AFPs) enable organisms to survive under cold conditions, and have great potential in improving cold tolerance of cold-sensitive plants, In order to determine whether expression of the carrot 36 kD antifreeze protein gene confers improved cold-resistant properties to plant tissues, we tried to obtain transgenic tobacco plants which expressed the antifreeze protein. Cold, salt, and drought induced promoter Prd29A was cloned using PCR from Arabidopsis. Two plant expression vectors based on pBI121 were constructed with CaMV35S:AFP and Prd29A:AFP. Tobacco plantlets were transformed by Agrobacterium-medicated transformation. PCR and Southern blotting demonstrated that the carrot 36 kD afp gene was successfully integrated into the genomes of transformed plantlets. The expression of the afp gene in transgenic plants led to improved tolerance to cold stress. However, the use of the strong constitutive 35S cauliflower mosaic virus (CaMV) promoter to drive expression of afp also resulted in growth retardation under normal growing conditions. In contrast, the expression of afp driven by the stress-inducible Prd29A promoter from Arabidopsis gave rise to minimal effects on plant growth while providing an increased tolerance to cold stress condition (2℃). The results demonstrated the prospect of using Prd29A-AFP transgenic plants in cold-stressed conditions that will in turn benefit agriculture.  相似文献   

15.
Analysis of synonymous codon usage in chloroplast genome of Populus alba   总被引:1,自引:0,他引:1  
Meng Zhou  Wei Long  Xia Li 《林业研究》2008,19(4):293-297
The pattern of codon usage in the chloroplast genome of Populus alba was investigated. Correspondence analysis (a commonly used multivariate statistical approach) and method of effective number of codons (ENc)-plot were conducted to analyze synonymous codon usage. The results of correspondence analysis showed that the distribution of genes on the major axis was significantly correlated with the frequency of use of G+C in synonymously variable third position of sense codon (GC3S), (r=0.349), and the positions of genes on the axis 2 and axis 3 were significantly correlated with CAI (r=-0.348, p〈0.01 and r=0.602, p〈0.01). The ENc for most genes was similar to that for the expected ENc based on the GC3s, but several genes with low ENc values were lying below the expected curve. All of these data indicated that codon usage was dominated by a mutational bias in chloroplast gcnome ofP. alba. The selection in nature for translational efficiency only played a minor role in shaping codon usage in the chloroplast genome ofP alba.  相似文献   

16.
Cottonhead windhairdaisy (Saussurea laniceps Hand.-Mazz.) is one of the most famous and important medicinal herbs in China. Illegal collection from wild populations is increasingly threatening the present environment of S. laniceps. Establishment of an efficient method for micropropagation is the best way to change its endangered situation. When mature seeds of S. laniceps were cultured on hormone-free MS medium, plantlets were formed from germinated seeds in 7–10 d. Then 0.5 cm × 0.5 cm leaf explants were transplanted to MS medium supplemented with 1-naphthalene-acetic acid (NAA)/2,4-D and benzyladenine (BA)/KT and callus was achieved 10 d after transfer. Shoot bud regeneration occurred from callus cultured on MS medium supplemented with different growth regulators 20 d after culturing. The regeneration percentages varied with the different components of plant growth regulators. The percent regeneration from callus pretreated at low temperature of 5°C increased significantly compared with those incubated at 23/20°C directly. Optimal regeneration was observed with explants on media supplemented with 1.5 mg&#8226;L–1 BA plus 0.2 mg&#8226;L-1 NAA. In the presence of 0.2 mg&#8226;L–1 NAA in half-strength MS, 78% of the shoots formed roots. Plantlets from explants showed 63% survival after acclimatization.  相似文献   

17.
Bio-control trials of Chaetomium spirale ND35 against apple canker   总被引:1,自引:0,他引:1  
A new endophytic antagonistic fungus, Chaetomium spirale ND35 from Populus tomentosa, was reported. The bio-control trials of C. spirale ND35 against the Valsa Canker of apple were preliminarily investigated. The results of dual culture on PDA plate showed that C. spirale ND35 was capable of strong antagonism against Valsa ceratosperma, and for inhibiting the mycelial growth of V. ceratosperma,.the crude extract of liquid culture of corn steep powder broth was more effective than that one of malt extract broth (MEB). The results of bio-control in greenhouse and field indicated that the disease incidence of apple tree treated with C. spirale ND35 was lower significantly than that treated by other methods. The re-isolation experiment suggested that C. spirale ND35 could colonize in stems and branches of apple trees successfully, and the ND35 colonization rate of the treatment with solid wheat bran culture was higher than that of corn steep powder broth, but the field experiment result the control effect of liquid culture of C. spirale ND35 was better than that of solid culture.  相似文献   

18.
We examined variations in stand structure and tree growth of a mangrove forest along two gradients: from the river mouth to upper stream and from the riverside to inland, along the Nakara River, Iriomote Island, Japan. Bruguiera gymnorrhiza (L.) Lamk. occurred throughout the intertidal area, though Rhizophora stylosa Griff. and Kandelia candel (L) Druce did not occur upstream. Basal area and maximum tree height of B. gymnorrhiza decreased downstream. The growth rate in stem diameter of B. gymnorrhiza decreased downstream in relation with the soil salinity. The basal area and the maximum tree height of B. gymnorrhiza increased with the distance from the riverside. R. stylosa increased in stem diameter and growth rate toward the riverside.  相似文献   

19.
Phylogenetic relationships ofArundinaria and related genera (Pleioblastus, Pseudosasa, Oligostachyum, Bashania, Clavinodum, etc.) were assessed by analyzing the sequences of the nrDNA internal transcribed spacer (ITS) and the cpDNAtrnL-F intergenic spacer (IGS). Comparison withtrnL-F IGS sequence, the ITS region provided the higher number of parsimony informative characters, and the interspecific variation of the ITS sequence was higher than that of thetrnL-FIGS sequence. The tree obtained by combining both sets of data showed that the species sampled inArundinaria and the related genera were monophyletic and divided into two clades. The relationships and positioning of all the taxa surveryed (includingA. oleosa, A. hsienchuensis, A. chino, A. amara, A. yixingensis, A. amabilis, A. fortunei, A. pygmaea, A. gramineus, A. fargesii, A. faberi, A. hupehense, Pseudosasa japonica cv. Tsutsumiana, P. japonica andBrachystachyum densiflorum) were also discussed. The results from the sequences were broadly consistent with morphological characters, appearing all these taxa sampled belong to the genus ofArundinaria. The topologies of the trees generated from individual data and the combined data were similar. Foundation item: This study was supported by National Natural Science Foundation of China (No. 30170788) Biography: ZHUGE Qiang (1959-), male, professor in Laboratory of Forest Genetics and Gene Engineering, Nanjing Forestry University, Nanjing 210037, P.R. China. Responsible editor: Song Funan  相似文献   

20.
In the Shennongjia National Nature Reserve of Central China, the vegetative growth behavior of henon bamboo (Phyllostachys nigra var.henonis (Mitford) Stapf. ex Rendle) was studied from shoot recruitment to culm establishment. In May, bamboo shoots emerging from the ground achieved an average density of 2.7 shoots m−2 during the sprouting phase of 16 days. However, about 32% of the new shoots died back before maturity. Insect damage, withering death and rodent predation were responsible for 57%, 29% and 14% of the total shoot mortality, respectively. From May to June, the shoots attained 400±23 cm during the height growth phase of 34 days, with a daily rate varying from 1 to 56 cm. All branches and leaves unfolded during the branch spreading phase from June to August. Shoot production was positively related to the density of standing culms, but negatively to both coverage and height of herb layers. Foundation item: This research was financed by the Center for Development Research (ZEF) of the University of Bonn, Germany (P. 52015), the National Natural Science Foundation of China (No. 30470284) and the Scientific Research Foundation for the Returned Overseas Chinese Scholars (No. 2004-527). Biography: Li Zhao-hua (1964-), male, Doctoral of Natural Science (Bonn University), Professor of Ecology (Hubei University, Wuhan 430062, P. R. China). Responsible editor: Chai Ruihai  相似文献   

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