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1.
The activity of antioxidant enzymes and ultrastructural changes in tissues inoculated with P. infestans isolate have been studied in the previously developed independent transgenic lines of tomato with FeSOD1 gene and control plants. It is shown that the activity of superoxide dismutase is significantly higher in transgenic plants than that in control plants (nontransgenic plants). Chlorosis and obvious changes in tissue turgor were observed when the control tomato plants were inoculated, which indicates irreversible damages and unimpeded progression of infection. At the same time, the transgenic lines were characterized by the formation of clearly limited zones of damaged cells that rapidly arrested the infection. In addition, the damages differed from those in nontransgenic plants: the cells along the edges of the infection site were smaller and had heavy invaginations of the cell wall. The contacts between the cells were disrupted in this zone, but they were preserved in undisturbed zones of the tissue. Thus, the expression of the FeSOD1 transgene promotes the emergence of the resistance to P. infestans in tomato transgenic plants.  相似文献   

2.
The objectives of our present study were to isolate antagonistic Streptomyces from tomato rhizosphere, and evaluate the potential strain for the biological control of bacterial canker of tomato. One hundred and seventy strains of isolated from tomato rhizosphere were tested for antibiosis activity against Clavibacter michiganensis subsp. michiganensis on double-layer agar. Sixty-three isolates showed antibiosis activity with diameter of an inhibition zone ranging from 1.0–6.5 cm. Fifteen Streptomyces strains had strong antibiosis activity against C. m. subsp. michiganensis with diameter of the inhibition zone above 4.0 cm on double-layer agar. Especially, the strain named Z-L-22 showed the strongest antibiosis activity with 6.5 cm inhibition zone. The fermentation filtrate also showed a high inhibition activity against Gram-positive bacteria such as Streptomyces scabies, Staphylococcus aureus, and Bacillus subtilis. Morphological, physiological and biochemical tests combined with 16S rDNA sequence analysis were carried out to identify the strain Z-L-22. Characteristics of the Z-L-22 were similar to those of Streptomyces setonii, and the 16S rDNA sequence showed 99.4% homology to S. setonii. Based on the polyphase taxonomic views, the Z-L-22 was identified as S. setonii.  相似文献   

3.
The resistance of transgenic tomato plants containing genes of chitin-binding proteins from Amaranthus caudatus (ac) and A. retraflexus (RS-intron-Shir) and hevein-like antimicrobial peptides (amp1 and amp2) from Stellaria media is analyzed. Lines expressing genes ac, amp1, and amp2 are characterized, unlike the untransformed control, by enhanced resistance to a isolate Phytophthora infestans obtained from potato leaves.  相似文献   

4.
The allelopathic influence of aqueous extracts of Thymus kotschyanus on Bromus tomentellus and Trifolium repens germination (%), germination speed, and seedling growth (length, fresh and dry weight) was examined. It was noted that aqueous extracts had a considerable inhibitory effect on target plant germination, and the effect at 50%, 75%, and 100% concentration was found to be significantly higher than that at lower concentrations (5% and 25%) and control treatment (distilled water). Seedling length in addition to fresh and dry weights was also reduced significantly over control. The inhibitory effect was increased as the extract concentration was increased. B. tomentellus showed a higher sensitivity against T. kotschyanus in allelopathic effects compared to T. repens, which indicates that B. tomentellus planted in rangelands with leaf litter of T. kotschyanus will be adversely affected in terms of its germination, growth, and ultimately low forage production.  相似文献   

5.
The chalcone synthase gene (chs) from Ginkgo biloba L. was cloned by PCR procedure. For constructing a plant expression vector of Gbchs, the gene was digested with XbaI and BamHI and inserted into the pBI121 vector. Gbchs was transferred into tobacco mediated by Agrobacterium tumefaciens LBA4404. PCR and Southern blot were performed, and the results showed that chs had been transformed into the genomic DNA of tobacco. The total flavones in the transformed tobacco leaves was extracted by the methanol extraction method and tested by UV spectrophotometry. The results showed that, compared to the control tobacco, the content in the transgenic tobaccos, n = 6, was generally higher, and the difference reached a significant level (P < 0.05) and highly significant level (P < 0.01), except one sample. Moreover, the highest sample was nearly 7.7 times greater than that of the controls. All these results show that utilizing genetic manipulations to improve plants in order to regulate flavone content by gene engineering may be an effective and hopeful method.  相似文献   

6.
The response of wheat varieties and breeding lines to vernalization and photoperiod in pot experiments is studied and tested by means of allele-specific markers for genes Ppd and Vrn. These markers effectively predict the degree of photoperiod sensitivity of plants to vernalization, which attests to the expediency of using them in breeding practice.  相似文献   

7.
It is shown that constitutive hyperexpression of new hevein-like peptides from the weed plant chickweed (Stellaria media)in mouse-ear cress (Arabidopsis thaliana) plants leads to a substantial increase of their resistance to phytopathogenic fungi Botrytis cinerea and Bipolaris sorokiniana. Thus, common chickweed peptides can play a definite role in protecting this weed plant and be useful as a new genetic tool for producing plants resistant to fungal diseases.  相似文献   

8.
韩媛媛  常亚文  姚舒  毛念  纪兆林 《安徽农业科学》2013,(22):9197-9199,9334
[目的]探讨转截短hpalXoo基因烟草中与抗病性有关的5种防御酶系的活性变化.[方法]以转截短hpalXoo基因烟草A6-1和对应的非转基因烟草Xanthi叶片为材料,接种烟草花叶病毒(TMV),测定苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)的活性.[结果]未接TMV时,转截短hpalXoo基因烟草中POD、PPO和CAT酶活性均高于未转基因对照品种,而SOD和PAL活性与未转基因烟草无显著差异.接种TMV后,转截短hpalXoo基因烟草中5种防御酶活性均显著增加,且高于未转基因烟草,并维持在一个较高的水平.[结论]截短的hpalXoo基因在烟草中表达能显著提高其抗病防御酶活性水平.  相似文献   

9.
In order to explore the influence of crust-covered paving on city landscape plants, the photosynthesis and chlorophyll fluorescence parameters of Firmiana simplex were studied in this paper by the LCI portable plant photosynthesis meter and the OS5-FL-mode pulse modulated chlorophyll fluorometer. The results showed that during the day, the net photosynthetic rates of Firmiana simplex leaves under the crust-covering stress were slightly lower than those of the control, and the differences were significant at 18:00; the transpiration rate of the treatment group showed a single-peak curve, with the peak appearing between 12:00–14:00, while the transpiration rate of the control group showed a bimodal curve with the peak appearing at 10:00 and 16:00, respectively. When the transpiration rate of the control showed a low peak at 14:00, the transpiration rate of treatments was very significantly higher, and the difference was as much as 45.08%. In addition to 16:00 of all day, the water use efficiency of Firmiana simplex leaves under crust-covered condition was slightly higher than that of the control; the differences were not significant in the morning but very significant in the afternoon. The stomatal conductance of treatments was significantly higher than that of the control at 14:00 and slightly lower than the control at any other time. The intercellular CO2 concentration of treatments was higher than that of the control during the day except at 16:00, and the difference was significant at 14:00 and 18:00. The maximal photochemical efficiency of PS II (Fv/Fm) and the potential activity of PS II (Fv/Fo) of treatments were both lower than those of the control during the day except at 18:00, with very significant differences at 14:00. By this token, we concluded that the crust-covered paving had somehow brought a certain stress to the city landscape plant, Firmiana simplex.  相似文献   

10.
RUS1 was one of the disease resistance gene analogs obtained from Setaria italica Beauv. Semi-quantitative RT-PCR analysis result showed that RUS1 gene could be induced by Uromyces setariae-italicae and had relation to the resistance response of Setaria italica Beauv. against Uromyces setariae-italicae infection. Promoter sequence of RUS1 was obtained by the method of Genome Walking, and its length was 675 bp. RUS1 promoter and pCAMBIA1300 vector were fused to construct RUS1::GUS vector. GUS histochemical staining result showed that promoter could activate gene expression. RUS1 gene (including the promoter sequence) was obtained through PCR amplification and then fused with pCAMBIA1300 vector to construct pCAMBIA1300:RUS1 plant expressing vector. The research laid a foundation for gene functional identification of RUS1.  相似文献   

11.
To identify resistance to Fusarium head blight (FHB), cereal yellow dwarf virus (CYDV), stem rust (Sr), and powdery mildew (Pm) in 24 common wheat (Triticum aestivum)-Leymus multicaulis addition/translocation lines that were developed cytogenetically and to verify the authenticity of these lines using microsatellite (SSR) DNA markers. Resistance to FHB was identified in the wheat-L. multicaulis addition lines, Line 9 and Line 26, which both contained L. multicaulis-specific fragments as shown by SSR markers. The translocation line, Trans 1, and the addition lines, Line 5 and Line 29, have resistance to stem rust (IT 0). Resistance to CYDV was evaluated based on virus titers measured by enzyme linked immunosorbent assay (ELISA). The addition line, Line 23, showed low virus titer (0.15), indicating resistance to CYDV. The segregation distribution of CYDV resistance in 98 F2 plants of Line 23/CS showed a significant deviation from 3:1. Inoculation with a set of 14 differential Blumeria graminis f. sp. tritici (Bgt) isolates did not detect powdery mildew resistance in translocation line Trans 1, addition line Line 9 and the amphiploid of wheat-L. multicaulis. However, Line 26 exhibited the resistance response pattern of Kavkaz, which carries Pm8, indicating that Line 26 most likely has the powdery mildew resistance gene Pm8 inherited from its parent lines Feng Kang 7 or Feng Kang 10. Twelve SSR markers, distributed on different homeologous chromosome groups of wheat, which distinguished L. multicaulis addition/translocation chromosomes, were used to verify the presence of L. multicaulis chromatin in the putative wheat-L. multicaulis addition/translocation lines. Of the 24 addition/translocation lines investigated using the 12 polymorphic SSR markers, 18 wheat-L. multicaulis derivatives showed the expected L. multicaulis-specific fragments, indicating that all of these 18 addition/translocation lines would most likely have the introgressed L. multicaulis chromosome(s). Chromosomal rearrangements also were detected in some of the wheat-L. multicaulis introgression lines.  相似文献   

12.
以转ZmPP2 C2基因烟草和非转基因烟草为材料(NC89),采用聚乙二醇(PEG-6000)处理,研究水分胁迫对转ZmPP2 C2基因烟草叶片膜脂过氧化及抗氧化酶活性的影响。结果表明:在15%PEG-6000模拟水分胁迫条件下,随着处理时间的延长,2种烟草叶片的相对电导度、MDA含量及POD活性都呈上升趋势。但转基因烟草相对电导度和MDA含量上升较非转基因烟草低,POD活性的增加明显高于非转基因烟草。胁迫10 d时与胁迫0 d相比,转基因烟草和非转基因烟草POD分别上升了483.54和212.38%,2种烟草SOD活性均表现为先上升后下降,但转基因烟草下降幅度小,且保持比较高的活性。试验结果说明,干旱胁迫下,转ZmPP2 C2基因烟草叶片具有较高的抗氧化酶活性,膜脂过氧化程度低于非转基因烟草。  相似文献   

13.
外源GO基因导入番茄后对叶霉病的抗性机制   总被引:1,自引:0,他引:1  
【目的】研究转GO基因番茄的抗病机制。【方法】通过测定转GO基因番茄和对照未转基因番茄接种叶霉菌Fulvia fulva后,体内超氧物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、多酚氧化酶(PPO)和苯丙氨酸解氨酶(PAL)的活性变化。【结果】接种后转基因番茄株系的SOD、POD、CAT活性均比对照明显增加,且转基因番茄的活性高峰比对照早。转基因番茄在接种后PAL和PPO活性都出现2个活性高峰,且第2个峰值比第1个高,而对照只有1个活性高峰,其总体水平明显低于转基因番茄。用番茄叶霉病(Fulvia fulva)病原菌1.2.3.4生理小种侵染T1代转基因植株。【结论】 结果显示转基因番茄植株的抗病性有不同程度的提高,多数发病时间推迟,病情明显减轻。  相似文献   

14.
Powdery mildew, caused by Blumeria graminis f. sp. tritici, is one of the most important fungal diseases in common wheat (Triticum aestivum L.) worldwide. Wheat germplasm N9436 is resistant to powdery mildew. In the present study, a backward subtracted cDNA library was constructed with cDNA from N9436 leaves inoculated by Blumeria graminis as the driver and cDNA from uninoculated N9436 leaves as the tester. A total of 120 positive clones were randomly chosen from the SSH-cDNA library and were amplified with sp6 and t7 primers to examine the insert size. After screening the repeated and redundant sequences, 59 expressed sequence tags (EST) were acquired. Nucleic acid and protein homology search were performed using the basic local alignment search tool (BLAST) program with the default settings at NCBI website (http://www.ncbi.nlm.nih.gov). BlastX results in nr-protein database revealed that 23 ESTs were highly homologous with known proteins involved in primary metabolism, energy metabolism, transport, signal transduction, and disease resistance and defenses. BlastNr results showed that 47 and 10 ESTs had high identities with known Unigene and function-unknown ESTs, respectively, and two ESTs matched none in the nr-database. Twenty-one ESTs were both in the nucleic acid and protein databases, including seven ESTs associated with powdery mildew resistance. Among them, one was responsible for signal transduction and six for systemic acquired resistance (SAR) system.  相似文献   

15.
利用卡那霉素筛选烟草转基因植株的技术研究   总被引:2,自引:0,他引:2  
待供试材料转基因和非转基因云烟87烟株长至5~7片叶时,在第3片叶上连续5 d喷施400 mg/L的卡那霉素溶液,喷后2 d观察,结果非转基因云烟87烟株叶片全部产生黄色斑点,而带有卡那霉素抗性标记基因的转基因云烟87烟草叶片表现正常。利用此方法对转基因烟草T2代3个株系进行筛选,筛选出22株转基因烟草植株,并用PCR方法对此方法的准确性进行了验证,结果表明,此方法对转基因烟草是一种简单快速的筛选方法。  相似文献   

16.
钾营养对番茄光合作用和产量形成的效应   总被引:11,自引:0,他引:11  
用盆栽试验研究钾营养对番茄光合作用和产量形成的效应,结果表明适量施钾明显增大叶面积,且叶的维管束较发达,净光合率提高并可缓和“午休”现象,光合产物增多.净光合率的提高与气孔导度及水势的提高有一致趋势.电镜观察表明适当施钾的叶绿体呈扁圆形,基粒较多,而缺钾叶绿体则较小而圆,基粒较少,在叶绿体旁有较多线粒体及过氧化体;钾过多的处理在前期光合及生长均受抑制,电镜观察其叶绿体发现其中少量有片层结构失常的情况,积累大量淀粉粒.基粒结构不明显,但开花结实后抑制作用渐消失.施钾使植株上、中、下层叶片在结实期都保持较高叶绿素含量;单果重及单株果数均增高,产量明显增加,果实维生素C及红色素含量提高,品质较好.  相似文献   

17.
The effect of variants of the action of allele lsb differing in strength of manifestation on productivity of buckwheat plants against the background of a recessive homozygote for gene D is studied. An increase of reduction of the branching potential of upper branches leads to a decrease in both biological and grain productivity of plants. However, such plants are much more tolerant to thick planting and to a lesser degree they reduce productivity in a dense crop.  相似文献   

18.
Previous work in the agri-food tradition has framed food auditing as a novelty characteristic of a shift to neoliberal governance in agri-food systems and has tackled the analysis of food “quality” in the same light. This article argues that agri-food scholars’ recent interest in the contested qualities of food needs to be situated alongside a much longer history of contested cultural attributions of trust in food relations. It builds on an earlier discussion suggesting that, although neoliberalism has undoubtedly opened up new spaces for audit activity, older political and social dynamics operating around food audits were established long before the neoliberal historical moment. Breaking new ground (as far as is known) by looking further back than the early history of the organic social movement, it examines intersections of religious food auditing, migrant food culture, and commercial dynamics in food systems. Based on secondary sources, two contrasting case studies are presented to illustrate the flux and complexity for: New World Diaspora migrants to New York City of assuring food was kosher; and more recent Maghrebi migrants to southwest France of assuring food is halal. The article concludes by noting that the neoliberal moment stands not as the unique progenitor of a new style of food authority, but rather as the latest response to a wider rupture in the historically contingent arbitration of new forms of trust in food.  相似文献   

19.
TYLCV侵染对番茄叶片解剖结构和保护酶系统的影响   总被引:2,自引:0,他引:2  
1材料与方法 1.1材料番茄黄化曲叶病毒(TYLCV)是由烟粉虱以持久方式传播,机械接种传毒,但较困难;种子不带毒,植株间接触也不传毒,所以该试验依靠烟粉虱传播使材料获得病毒表现症状。毒原为上海农科院园艺所保持的带有TYLCV的烟粉虱。2006年7月中旬将番茄材料播种在50孔的穴盘中,以草炭为基质,8月中旬定植在具有足够传播TYLCV烟粉虱的玻璃温室内,每天间断性的驱赶,使烟粉虱充分接触试验材料。供试番茄是对TYLCV的感性品种“2300”,健康植株品种“2300”定植在没有毒源的温室内为对照。  相似文献   

20.
Plants need various micro and macronutrients for their growth and metabolism. Of these nickel (Ni) plays a role of micronutrient but causes adverse effects when present above optimum level. To combat such situations plants possess different growth regulators. Jasmonates are a class of plant growth regulators modulating various growth and physiological responses in plants. Aiming to evaluate the effect of nickel and jasmonic acid on growth and antioxidant enzymes Superoxide distmutase (SOD), Catalse (CAT), Ascorbate peroxidase (APX), Guaiacol peroxidase (GPX) and glutathione reductase (GR), seeds of Zea mays L. were sown in field after giving presowing treatment of NiSO4 · 6H2O (8 mM), jasmonic acid JA (10–6, 10–8 and 10–10 M) alone and JA (10–6, 10–8 and 10–10 M) in 1: 1 combination with NiSO4 · 6H2O (8 mM) in plant conservatory, Punjabi University, Patiala, Punjab, India. Plants of each treatment group were then subjected to spraying treatment with the respective treatment solutions at regular intervals of 22 days up to 66 days after sowing (DAS). The present findings signified reduced growth with Ni treatment but co-application of JA alleviated the effect of nickel through activity of antioxidant enzymes.  相似文献   

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