首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 250 毫秒
1.
To establish a highly efficient plant regeneration system for wheat genetic transformation, the effects of three different concentrations of dicamba and two different sugar types on callus induction and plant regeneration from mature embryo cultures were evaluated. Callus induction and plant regeneration were obtained from mature embryos of two commercial cultivars Zhoumai 18 and Yumai 34 (Triticum aestivum L.) cultured on L3 basal medium. The results showed that the efficiency of mature embryo culture was significantly influenced by the genotypes, sugar types and dicamba concentrations. 4 mg L^-1 dicamba proved the best effective for inducing embryogenic callus and also gave the highest proportion of plants regenerated across the two cultivars. Substitution of maltose by sucrose significantly improved the plant regeneration efficiency in both cultivars. There was a significant interaction between genotype-by-sugar types, and sugar types-bydicamba concentrations. Overall, Zhoumai 18 gave the highest frequency of plant regeneration (82.65%) when dicamba concentration was 4.0 mg L^-1 and with sucrose in initial callus induction. These results will facilitate genetic transformation work with elite wheat.  相似文献   

2.
Alfalfa (Medicago sativa L.) is an important forage crop in the world and it is of great signiifcance for the improvement of its salt tolerance. To improve salt tolerance in alfalfa, a rice ascorbate peroxidase gene (OsAPX2) was introduced into alfalfa using Agrobacterium tumefaciens-mediated transformation with marker gene bar. The different T-DNA insertions in T1 transgenic alfalfa were identiifed by Southern hybridization. Three independent T2 transgenic lines were selected for stress analysis and the results showed that all of them were salt tolerant compared with wild-type plants. The transgenic plants had low levels of H2O2, malondialdehyde and relative electrical conductivity under salt and drought stresses. Moreover, the contents of chlorophyll and proline, and APX activity were high in transgenic plants under salt and drought stresses. Taken together, the overexpression of OsAPX2 enhances salt tolerance in alfalfa through scavenging reactive oxygen species.  相似文献   

3.
Genetic transformation is an important technique for functional genomics study and genetic improvement of plants. Until now, Agrobacterium-mediated transformation methods using cotyledon as explants has been the major approach for cucumber, and its frequency has been up to 23%. For example, significantly enhancement of the transformation efficiency of this plant species was achieved from the cotyledon explants of the cultivar Poinsett 76 infected by Agrobacterium strains EHA105 with efficient positive selection system in lots of experiments. This review is to summarize some key factors influencing cucumber regeneration and genetic transformation, including target genes, selection systems and the ways of transgene introduction, and then to put forward some strategies for the increasing of cucumber transformation efficiency. In the future, it is high possible for cucumber to be potential bioreactor to produce vaccine and biomaterials for human beings.  相似文献   

4.
Since maize is one of the most important cereal crops in the world,establishment of an efficient genetic transformation system is critical for its improvement.In the current study,several elite corn lines were tested for suitability of Agrobacterium tumefaciens-mediated transformation by using immature embryos as explants.Infection ability and efficiency of transformation of A.tumefaciens sp.strains EHA105 and LBA4404,different heat treatment times of immature embryos before infection,influence of L-cysteine addition in co-cultivation medium after transformation,and how different ways of selection and cultivation influence the efficiency of transformation were compared.Glyphosate-resistant gene 2mG2-EPSPS was transformed into several typical maize genotypes including 78599,Zong 31 and BA,under the optimum conditions.Results showed that the hypervirulent Agrobacterium tumefaciens sp.strain EHA105 was more infectious than LBA4404.Inclusion of L-cysteine(100 mg L-1) in co-cultivation medium,and heating of the immature embryos for 3 min prior to infection led to a significant increase in the transformation efficiency.Growth in resting medium for 4-10 d and delaying selection was beneficial to the survival of resistant calli.During induction of germination,adding a high concentration of 6-BA(5 mg L-1) and a low concentration of 2,4-D(0.2 mg L-1) to regeneration medium significantly enhanced germination percentage.Using the optimized transformation procedure,more than 800 transgenic plants were obtained from 78599,Zong 31 and BA.By spraying herbicide glyphosate on leaves of transgenic lines,we identified 66 primary glyphosate-resistant plants.The transformation efficiency was 8.2%.PCR and Southern-blot analyses confirmed the integration of the transgenes in the maize genome.  相似文献   

5.
In the protocol of wheat transformation, to use elite wheat cultivars as exogenous gene recipients can speed up the process of commercial field applications of transgenic wheat. However, it is necessary to screen wheat cultivars with good tissue culture response (TCR) continuously from plenty of elite wheat cultivars released for wheat transformation, and it is also important to find a plant regeneration system that is suitable for these cultivars. So, the TCR of mature and immature embryos of six wheat cultivars Chuannong 11 (CN11), Chuannong12 (CN12), Chuannong17 (CN17), Chuannong18 (CN18), Chuannong19 (CN19), and Chuannong21 (CN21), which possess superior agronomic traits, were investigated by using a good TCR wheat cultivar Bobwhite as control. The results indicated that only the immature and mature embryos of CN12, CN17, and CN18 exhibited good TCR compared with Bobwhite. No significant differences were observed between embryos of Bobwhite and of the three cultivars in TCR. Mature embryo-derived calli of CN12 were used as explants for transformation by particle bombardment of SAMDC gene. Seven transformants were obtained and the efficiency was 2.3%. This research supplies three new elite recipient cultivars for wheat transformation. The wheat plant regeneration system used in this research is different from those successful ones reported previously and it could be a reference for other wheat genotypes. Furthermore, Bobwhite and the three wheat cultivars were proved to be 1RS/1BL translocation, by methods of A-PAGE, C- banding, and genomic in situ hybridization (GISH). These results imply that probably there is some relationship between 1RS/1BL translocation and TCR of wheat embryos. So this research gives us a hint that we should pay more attention to the 1RS/1BL translocations when we screen the wheat cultivars with good TCR and also that the mechanism of the effect of 1RS/ 1BL translocation on TCR is worthy of being investigated.  相似文献   

6.
Soybean is one of the most important sources of edible oil and proteins in the world.However,it suffers from many kinds of fungal diseases which is a major limiting factor in soybean production.The fungal disease can be effectively controlled by breeding plant cultivars with genetic transformation.In this study,the resistance to Phytophthora sojae of five bivalent transgenic soybean lines was identified using the hypocotyls inoculation technique.The lines were the T,of the transgenic soybean which were transformed with kidney bean chitinase gene and barley ribosome inactivating protein gene,and were positive by Southern Blot analysis.The resistance difference was studied through comparing the death percentage of transgenic soybean with the control.The results showed that four lines were more resistant to P.sojae,whereas other one had no significant difference in comparison with the control.These transgenic soybean lines with enhanced resistance to P.sojae will be useful in soybean resistance breeding.  相似文献   

7.
A novel insecticidal gene crylAh was cloned from Bacillus thuringiensis isolate BT8 previously for plant genetic engineering improvement. Truncated active CrylAh toxin has a toxicity level similar to that of the full-length CrylAh toxin. In this study, plant expression vector pMhGM harboring truncated crylAh gene was transformed into maize (Zea mays L.) immature embryos by Agrobacterium tumefaciens-mediated transformation at which maize alcohol dehydrogenase matrix attachment regions (madMARs) were incorporated on both sides of the gene expression cassette to improve gene expression. A total of 23 PCR positive events were obtained with a transformation efficiency of 5% around. Bioassay results showed that events 1-4 and 1-5 exhibited enhanced resistance to the Asian corn borer (Ostriniafurnacalis). These two events were further confirmed by molecular analysis. Southern blot suggested that a single copy of the crylAh gene was successfully integrated into the maize genome. Western blot and ELISA showed that the foreign gene crylAh was expressed stably at high level in maize and could be inherited stably over generations. The results of a bioassay of T l-T4 transgenic maize plants indicated that the transgenic plants were highly toxic to the Asian corn borer and their resistance could be inherited stably from generation to generation. Thus, events 1-4 and 1-5 are good candidates for the breeding of insect-resistant maize.  相似文献   

8.
Wheat is the number one crop both in acreage and total yield in the world. Therefore, it is very important to improve wheat by gene engineering techniques even though it belongs to the plants insensitive to gene transformation, especially to Agrobacterium-mediated transformation. Wheat immature embryos of 1.0-1.5mm in size, C58c1 of Agrobacterium strain harboring pPTN249, pPTN270, pPTN254, and pSIS-GFP respectively (all the vectors contain the aphA selectable gene driven by enhanced 35S promoter and a target gene controlled by ubi promoter or E35S promoter), AB medium for Agrobacterium activate culture, WCC medium for co-culture, were used in this study. The embryos with 4 days of pre-culture were transferred onto selection medium with 10mg/L geneticin, 50mg/L ticarcillin, 50mg/L vancomycin, and 50mg/L cefotaxine after 30 minutes of infection and 2 days of co-cultivation with Agrobacterium. Followed callus production,shoot regeneration on selection medium, 114 resistant plantlets were obtained from 10 transformation experiments of four genotypes. By nptⅡ ELISA (nptⅡ enzyme assay), PCR, Southern blot and leaf bleach,29 positive plants were identified from two genotypes of Bobwhite and Yanglmai 10, with an average transformation efficiency of 0.82 %. The result tested by Southern blot also showed that the transgenic plants with single- copy integration of target gene took 65.52% among total positive plants. The ELISA value of transgenic plant was also related to the copies of alien DNA integrating into wheat chromosomes, the transgenic plants with single copy integration giving higher ELISA value than the ones with 2 or 3 copies integration.  相似文献   

9.
In order to improve stress tolerances of turf-type tall fescue (Festuca arundinacea Schreb.), Agrobacterium tumefaciens strain EHA105 carrying plasmid pCMD containing stress tolerance-related CBF1 gene from Arabidopsis thaliana was used to transform mature seeds-derived embryogenic calli of four cultivars. A total of 112 transgenic plants were regenerated from 32 independent lines and verified by histochemical detection of GUS activity, PCR assay and Southern hybridization analysis. The transformation frequency ranged from 0.92 to 2.87% with apparent differences among the cultivars. Stress tolerances of transgenic plants were enhanced, which was shown by the facts that transgenic plants had distinct growth superiority and significantly higher survival rate than non-transformed ones under high salinity and high osmosis stresses, and that relative electronic conductivity of in vitro leaves treated with low and high temoeratures, dehvdration and high salinity stresses was 25-30% lower in transgenic plants than in control plants.In addition,it was observed that growth of transgenic plants was inhibited due to constitutive overexpression of CBF1 gene under normal environmental conditions.  相似文献   

10.
Study on the Factors Influencing the Efficiency of Wheat Transformation   总被引:1,自引:0,他引:1  
Wheat transformation efficiency is closely related to several factors such as receptor genotype, constructed plasmid and selection procedure after bombardment or co-cultivation. In our study, several kinds of antibiotics, which were normally used in plant transformation to the selection genes of nptⅡ, bar and hpt,were tested for the optimal concentrations for wheat transformation. The results showed that 25 - 50mg/L of geneticin (G418) was suitable for the selection of nptⅡ, kanamycin or neomycin was not suitable for use. 3 5mg/L of phosphinothricin (PPT) or biolaphos could be used for the selection of bar, 100 - 150mg/L of hygromycin for the selection of hpt. Yangmai 158 and Yangmai 10 with high tissue culture response and good agronomic characteristics were screened from 25 potential Chinese wheat cultivars. The concentration changing of selectable agent in selection medium was helpful to obtain enough regeneration plantlets with strong root system.  相似文献   

11.
紫花苜蓿高频再生体系的建立有助于促进其遗传转化的研究。以陇东、阿尔冈金以及甘农4号紫花苜蓿为实验材料,比较了体细胞胚胎和丛生芽再生途径对于紫花苜蓿再生周期及频率的影响。并通过利用不同外植体、不同植物生长调节剂配比,以实现对这两种再生途径的进一步优化。实验结果表明:在三个苜蓿品种中,甘农4号的再生效果较好,下胚轴的再生频率较高,在愈伤诱导阶段添加2 mg/L 2,4-D、1 mg/L KT,胚状体诱导阶段添加1 mg/L KT、0.5 mg/L NAA可以达到较好的再生效果;在培养基中添加1 mg/L 6-BA、1 mg/L TDZ,则直接诱导丛生芽的效果最好;对比发现,丛生芽再生途径显示出较强的优越性,其再生时间仅10周,是紫花苜蓿再生体系建立的一种可选方式。  相似文献   

12.
通过对6种不同基因型苜蓿愈伤组织的形成能力、愈伤组织的分化能力的比较发现,不同苜蓿品种间的分化率存在显著差异(P<0.05),其中甘农1号分化率最高(42.9%);对甘农1号叶片、下胚轴及子叶等外植体的分化再生能力研究发现,叶片起源的愈伤组织分化时间短,且丛生芽形成数量高于下胚轴和子叶;再生芽可在B5培养基上成苗,并在蔗糖浓度为10 g/L的1/2 MS培养基上顺利生根.据此认为,苜蓿甘农1号叶片是适于做遗传转化的理想材料.利用RT-PCR方法扩增拟南芥螯合肽合成酶(AtPCS1)基因全序列构建了AtPCS1的植物表达载体pBI121-AtPCS1,为下一步AtPCS1基因转化苜蓿奠定了基础.  相似文献   

13.
农杆菌介导灰绿藜NHX1基因转化新疆大叶苜蓿的研究   总被引:2,自引:0,他引:2  
利用转基因技术能够快速有效地获得抗盐碱苜蓿的新品种,但苜蓿的品种直接影响着其再生能力和遗传转化,因此建立农杆菌介导的大叶苜蓿转基因体系对于大叶苜蓿抗逆新品种培育具有重要的促进作用.将新疆盐生植物灰绿藜(Chenopodium glaucum Linn.)的Na+/H+反向运输体基因Cg-NHX1构建在植物表达载体pBIN438上,并转化入根瘤农杆菌EHA105,以5~7 d苗龄的新疆大叶紫花苜蓿(Medicago.sativa)子叶为转化受体,通过重组EHA105介导的子叶浸染法将Cg-NHX1基因导入新疆大叶紫花苜蓿中,获得了抗卡那霉素的再生植株.提取转基因植株基因组DNA,进行PCR检测和Southern blot分析,结果表明Cg-NHX1基因已经被整合到新疆大叶紫花苜蓿基因组中.研究成功地获得灰绿藜NHX1基因转化的新疆大叶紫花苜蓿植株,并在新疆大叶紫花苜蓿遗传转化影响因素的研究中,发现菌液浓度OD600nm为0.2~0.3,浸染时间20 min适宜于子叶愈伤诱导,有利于基因转化植株的获得.  相似文献   

14.
对陇东苜蓿、大叶苜蓿、甘农3号和关中苜蓿4个感霜霉病品种进行了水杨酸喷雾试验,研究了水杨酸对苜蓿霜霉病的诱导抗性.结果表明,陇东苜蓿的诱导抗病效果最好,诱导效果可达61.8%,用不同浓度的SA诱导处理陇东苜蓿幼苗发现,SA诱导的最宜浓度为50μg/μL;SA诱导处理后,苜蓿幼苗体内过氧化物酶(POD)和苯丙氨酸解氨酶 (PAL)活性明显增强,POD、PAL在处理后第7 d、第5 d达到最大,分别为9.8(μ/g·hfw)和4.87(△OD/0.01 gfw),是对照的2.5倍和3.2倍.  相似文献   

15.
农杆菌介导的几个甘蓝型油菜下胚轴转化体系研究   总被引:1,自引:0,他引:1  
选择四川目前推广的中双9号等8个甘蓝型双低常规油菜品种,以5~6 d无菌苗下胚轴为外植体,MS培养基为基本培养基,设置了8组激素配比组合,探讨其对植株再生的影响,初步建立了不同油菜品种下胚轴的高效再生体系。选择其中再生频率较高的4个品种:中双9号、中双7号,中双6号,川油18号下胚轴作为农杆菌转化材料,对影响转化的相关因素进行研究,建立了4个品种下胚轴的遗传转化体系,并运用该转化体系将pta与sb401融合基因导入,成功获取了一批经PCR检测的转基因植株。  相似文献   

16.
农杆菌介导的柳枝稷遗传转化体系的优化   总被引:1,自引:0,他引:1  
【目的】为建立农杆菌介导的柳枝稷高效再生及遗传转化体系。【方法】试验以柳枝稷品种Alamo、Performer及Blackwell的成熟种子为外植体诱导愈伤组织。愈伤诱导6周后,借助解剖镜观察愈伤形态,去除愈伤组织外层含水量大、海绵状愈伤组织,挑选位于愈伤组织中心位置的核状、紧实型愈伤置于继代培养基培养。暗培养3周后,在解剖镜下挑选结构松脆、生长旺盛的愈伤组织按细胞系继代增殖培养。该类愈伤组织易于分化,属单子叶植物愈伤组织分类中的第Ⅱ型。经两次继代增殖培养后,可以获得足够的愈伤组织进行再生和遗传转化研究。为优化柳枝稷Ⅱ型愈伤组织的农杆菌侵染流程,试验比较了3种农杆菌侵染流程下的转基因效率。真空和干燥处理(VD):将装有愈伤组织及菌液的50 mL离心管置于真空泵中抽真空10 min(压力-0.8MPa),28℃, 80 r/min慢摇20 min后弃菌液,将愈伤组织堆放于3层滤纸上干燥处理2 h,随后将愈伤组织转入含有500 μL无菌水的2层滤纸上进行共培养;冷处理加真空和干燥处理(CVD):侵染前将愈伤组织置于3%麦芽糖、300 μmol·L-1谷氨酰胺(Gln)溶液中冰浴20 min,然后依VD流程侵染,共培养阶段用MP培养基代替无菌水;渗透冷处理加真空和干燥处理(PVD):用6%的麦芽糖溶液替代CVD中3%麦芽糖溶液。通过比较Gus染色及PCR阳性率来评价三种方法的转化效率。【结果】愈伤挑选方法不仅从柳枝稷低地型品种中挑选得到再生率达95%以上的Ⅱ型愈伤细胞系,也首次获得高地型品种Blackwell的Ⅱ型愈伤组织,分化率达50%。不同转化方法评价过程中发现,低地型品种AlamoⅡ型愈伤组织采用CVD农杆菌侵染流程转化效率最高,达72%,显著高于侵染流程VD(53%)和PVD(44%)。应用CVD转化法,Performer转化率达96%;首次成功进行了高地型品种Blackwell的遗传转化,转化效率为5.6%。【结论】本研究建立了借助解剖镜挑选柳枝稷易于再生的Ⅱ型愈伤组织的方法,该方法适用于柳枝稷不同生态型品种;农杆菌转化过程中采用CVD侵染流程可显著提高转基因效率。本研究首次报道了柳枝稷Ⅱ型愈伤组织的挑选流程,建立了适合不同生态型柳枝稷的高效再生及遗传转化体系,首次获得高地型品种Blackwell的转基因植株,为柳枝稷遗传改良及其功能基因研究奠定基础。该方法也适用与其他难于再生的单子叶植物再生及遗传转化体系的建立。  相似文献   

17.
徐春波  王勇  赵海霞  米福贵 《安徽农业科学》2012,(12):7161-7163,7170
[目的]建立苜蓿植株再生体系和农杆菌遗传转化体系。[方法]以"猎人河"苜蓿品种为受体材料,对影响苜蓿植株再生和遗传转化的相关因素进行了研究。[结果]最佳愈伤诱导培养基为改良SH+4.0 mg/L 2,4-D+0.5 mg/L 6-BA,最佳继代培养基为MSO+0.5mg/L NAA+1.0 mg/L 6-BA+1.0 mg/L AgNO3,而最佳分化培养基为MS,苜蓿植株再生的最佳外植体是下胚轴。苜蓿农杆菌遗传转化的选择压确定为60 mg/L卡那霉素(Kan),最适宜的抗菌素为350 mg/L羧苄青霉素(Carb),农杆菌菌液的最适OD600为0.6,最佳侵染时间为10 min。[结论]该研究为今后苜蓿的基因工程研究奠定了基础。  相似文献   

18.
通过对新疆呼图壁小海子地区不同品种,不同种植年限的苜蓿制种田和打草田进行大田定期定点调查苜蓿白粉病和霜霉病发生动态,初步对比分析了这几个因子与病害发生的关系.结果表明:种植一年的新疆大叶苜蓿前期较感霜霉病,而后期则表现与种植三年的新疆大叶对苜蓿霜霉病的抗病性没有明显差异;新牧1号与新疆大叶间抗病性差异显著;作为打草田,相同或不同品种此两种病害的发生并不因种植年限增加而明显加重.  相似文献   

19.
利用农杆菌混合液介导的共转化法,研究不同浓度的农杆菌混合液浸染5种水稻品种的愈伤组织,进而获得共转化再生植株。对转基因植株进行叶片潮霉素抗性检测和螟虫田间抗性鉴定的结果表明,农杆菌混合液浓度OD600为0.6左右时,其浸染能力较强;5个品种中以浙粳27的再生效率最高。转基因植株叶片经潮霉素抗性检测,潮霉素阳性率为78.13%,经PCR检测转基因植株Cry1A(b)基因阳性率为15.11%。自然抗性鉴定结果表明:Cry1A(b)基因阳性的转基因植株对稻纵卷叶螟具有很好的抗性。基因分离的鉴定结果表明:HPT基因与Cry1A(b)基因在共转化转基因植株的后代中发生了分离。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号