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1.
为了探索小麦成熟胚基因枪转化的影响因素,对Z50、郑麦366、Bobwhite和西农529四个小麦基因型的成熟胚进行了愈伤组织的诱导及植株分化再生研究,同时以郑麦366的成熟胚为外植体分析了不同渗透处理剂、每枪金粉用量和轰击距离对基因枪转化过程的影响。结果表明,Z50、郑麦366、Bobwhite三个基因型的出愈率及胚性愈伤率差异不大,均在85%以上,西农529的出愈率较低,胚性愈伤率与Z50、郑麦366和Bobwhite差异显著。不同小麦基因型分化率差异显著,其中郑麦366分化率最高(39.26%)。基因枪转化结果显示,渗透剂对小麦愈伤组织生长均有一定的抑制作用,蔗糖的抑制作用比甘露醇弱;每枪金粉用量100μg的分化率较高(45.57%),但金粉用量100μg时的GUS瞬时表达量与金粉用量60μg时差异不显著,轰击距离为9cm时的分化率和GUS瞬时表达量均比6cm和12cm时高;蔗糖用量0.4mol、金粉用量60μg、轰击距离9cm时GUS瞬时表达量最高,该条件下小麦成熟胚转化频率达0.67%,已初步优化了基因枪介导的小麦成熟胚遗传转化体系。  相似文献   

2.
为了建立和不断完善大麦单倍体细胞遗传转化体系,并突破其对模式品种的依赖,以2份大面积推广种植的优良大麦品种的花药为受体材料,利用基因枪法将GUS报告基因导入其小孢子,比较了不同基因型大麦花药经基因枪轰击后小孢子转化频率的差异,并探讨了不同轰击次数对小孢子转化频率的影响。研究结果表明,供试品种花药经基因枪轰击后,都有少量小孢子被成功转化,表现GUS活性;玉米泛素基因Ubi启动子能启动报告基因GUS在大麦小孢子中表达;基因枪轰击对小孢子的转化频率存在一定的基因型差异,两轰击处理组合下,品种"花22"的小孢子转化频率比"花30"的分别高出50.9%和77.8%;具有GUS活性的小孢子随轰击次数的增多而增加,轰击2枪较轰击1枪小孢子转化频率高出113.9%(花30)和77.6%(花22)。  相似文献   

3.
基因枪及其与农杆菌相结合的茶树外源基因转化条件优化   总被引:7,自引:0,他引:7  
以GUS为报告基因,对基因枪介导的转化茶树愈伤的有关参数进行优化。比较了不同的预培养条件,含有PVP的培养基可提高转化频率。渗透处理不仅不能提高GUS的表达率,反而使愈伤再生困难。每枪DNA和钨粉的用量分别为0.25μg,125μg时,可得到较高的转化率。在轰击压力7MPa,射程5cm的条件下轰击一次,不论对GUS表达还是愈伤的再生都是较为适合的轰击条件。比较了农杆菌法(AGR),基因枪法(BOM)及农杆菌与基因枪结合(BTA,BPA和BOA)等方法对茶树遗传转化效率的影响。瞬间表达的结果及抗性愈伤筛选的结果都显示,农杆菌与基因枪结合使用比两种方法单独使用更有助于提高茶树转化的效率。  相似文献   

4.
薛仁镐 《大豆科学》2008,27(2):194-198
以萌动1d的半片种子为靶组织,植物表达载体质粒pCAMBIA1301为外源DNA,通过GUS瞬时表达检测,研究了轰击次数、轰击距离、培养时间及靶组织放置方式对基因枪转化效率的影响。结果表明:轰击次数对转化效率有很大影响,轰击2或3次时GUS瞬时表达效率显著高于1次;在所试的3、6、9、12cm4个轰击距离中,9cm轰击距离对GUS瞬时表达效率最高;靶组织培养时间长短对转化效率也有很大影响,培养2d时,转化效率最高,平均每个半片种子达到217.5个蓝色斑点,随着培养时间的延长,GUS基因瞬时表达呈下降趋势,至第28天以后趋于稳定;靶组织不同放置方式对转化效率无明显的差异。本研究优化了影响基因枪法转化大豆萌动种子的主要因素,从而为基因枪介导大豆遗传转化技术体系的建立提供了参数。  相似文献   

5.
小麦遗传转化中潮霉素筛选体系的建立及应用   总被引:1,自引:0,他引:1  
为建立小麦遗传转化中高效的潮霉素筛选体系,以小麦品种郑麦9023的幼胚愈伤组织为材料,探讨了潮霉素浓度、处理时间、恢复培养与否对愈伤组织分化和再生的影响,并对基因枪转化的郑麦9023、邯6172、龙麦30、龙麦31的愈伤组织进行了筛选。结果表明,对小麦幼胚愈伤组织基因枪遗传转化后的筛选以50mg·L-1潮霉素处理30d为宜;恢复培养不能提高筛选阶段愈伤组织的存活率和分化率,但能提高转化后期的成苗率。经过筛选发现郑麦9023抗性愈伤和T0代抗性植株根系及花器官中均有GUS基因的表达;4个小麦品种抗性植株中潮霉素磷酸转移酶基因(hpt)和候选基因PCR阳性率分别为78.95%和73.68%以上;龙麦30、龙麦31的T1代植株的候选基因PCR阳性率分别在33.33%和73.33%以上,T2代阳性率分别在71.43%和75.00%以上。  相似文献   

6.
小麦不同转基因受体材料的植株再生培养研究   总被引:7,自引:4,他引:7  
为了确定适宜的小麦转基因受体材料,通过不同取材和预处理,发现小麦幼胚作为基因枪转化的受体材料,其愈伤组织形成与芽分化能力优于幼穗。幼胚在枪击前的预培养时间对愈伤组织抗轰击损伤和恢复生长能力都有明显影响,预培养2周的幼胚愈伤组织作为受体的再生率较高。在轰击前6h到轰击后18h用0.4mol·L-1甘露醇处理,能增加分化率。小麦基因型不同,基因转化与植株再生的效果也有明显差别,本研究中豫麦18-64是较理想的受体基因型。  相似文献   

7.
以超甜玉米自交系S1及其杂交种粤甜3号的幼胚为材料,通过优化基因枪转化条件,获得18个可育的转基因超甜玉米株系。研究结果显示,金粉直径、氦气压力和轰击距离等均影响基因枪的转化效率,用1.0μL金粉,轰击距离为12cm,压力为1100Pa时,转化效率最高。  相似文献   

8.
基因枪法获得玉米转基因植株的研究   总被引:2,自引:0,他引:2  
采用基因枪轰击转化技术将含有抗除草剂chlorsulfuron基因AHAS的PCD220质粒导入玉米愈伤组织,并再生出具有抗该除草剂的转基因植株,同时研究了影响玉米基因枪转化效率的因素。基因枪轰击时,金粉用量、轰击次数及轰击距离对愈伤组织的转化率有较大影响。转化时,以金粉用量100 μg/枪、轰击2次、发射点与靶细胞的距离9 cm最合适。对所获得的转化植株进行PCR分析及Southern杂交鉴定,部分转化植株呈PCR阳性和明显的杂交信号,说明抗除草剂绿黄隆的基因AHAS已整合到玉米基因组当中,将转基因植株进行自交,获得了T0代的种子。  相似文献   

9.
构建植物表达载体并利用该载体与含有选择压力基因的载体对小麦幼胚愈伤组织进行共转化。比较分析了高渗透压处理阶段使用0.4 mol/L的蔗糖(合12%)代替甘露醇及恢复培养阶段使用过渡浓度的蔗糖(6%,介于高渗透压培养基中蔗糖的浓度12%和分化培养基中蔗糖的浓度3%之间)对分化率和转化效率的影响。结果表明,在采用基因枪轰击法叶小麦幼胚愈伤组织进行转化的体系中,以蔗糖代替甘露醇进行高渗透压处理,进而使用含有较高浓度蔗糖的培养基进行恢复培养的方法简便有效,可以促进分化能力提高,转化效率可达2.1%。  相似文献   

10.
以玉米自交系E28的胚性愈伤组织为受体,分别利用农杆菌介导法和基因枪轰击法对携带有GUS基因和Bar基因的质粒进行转化,借助GUS基因的瞬时表达率和抗性愈伤组织比例建立体系,并对两种方法进行比较。农杆菌介导法以OD6000.6、浸染30 min、25℃共培养3 d、加入0.01%的silwet L-77为最佳参数;基因枪轰击法为4.5 MPa、11 cm轰击距离最佳参数。农杆菌介导法与基因枪轰击法的GUS瞬时表达率没有显著差异,基因枪法的抗性愈伤组织比例显著高于农杆菌介导法,基因枪轰击法较农杆菌介导法更有利于获得转基因后代。  相似文献   

11.
12.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

13.
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.  相似文献   

14.
15.
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.  相似文献   

16.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

17.
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.  相似文献   

18.
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact).  相似文献   

19.
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.  相似文献   

20.
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.  相似文献   

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