根癌农杆菌对健康和患丛枝病泡桐的遗传转化

选取健康及患丛枝病泡桐（Paulownia spp.)为材料,建立组织培养和植株再生系统,以茎段作为转化受体,诱导分化和生根的最佳激素组合分别是MS＋BA4mg/L NAA0.2mg/L和1／2MS＋KT0.5mg/L IBA0.25mg/L。芽分化频率可达22．8％。健康和患病泡桐的茎段经农杆菌共培养3d后,在附加50mg/Lm的选择分化培养基上培养20d左右再生出抗性芽,经培养、诱导生根,获得了转基因再生植株,建立了泡桐的遗传转化体系。PCR和Southern杂交检测证明外源基因已整合到泡桐的基因组,标记基因ITPⅡ在再生植株中也得到表达,同时对影响转化的一因素进行了探讨。     

Molecular Cloning and Sequence Analysis of DNA in Mycoplasma-Like Organism of the Paulownia Witches Broom

Partially purified mycoplasma-like organism (MLO) preparations were obtained from diseased paulownia with witches' broom (PWB). EcoR Ⅰ -Hind Ⅲ digested fragment of the total DNAs extracted from the preparations was Iigated into pGEM-3Zf (+) vector. The recombinant molecules were transformed into Escherichia coli strain DH5α. After screening by differential hybridization and identification with Dot and Southern blot hybridization analysis, two clones (A4, 1.69 kb and C42, 2.08 kb) were obtained. Their DNA inserts as probes hybridized only with total DNAs from PWB-diseased plants but not with extracts from healthy plants. Abundant (A+T) content was found in the sequences of DNA inserts from the two clones, 72.5% (A4) and 67.9% (C42, respectively, which possessed the character of DNA from mycoplasma spp.     

表达尾穗苋凝集素基因的转基因烟草对桃蚜(Myzus persicae)繁殖的影响(英文)

To investigate the possible function of the agglutinin from Amaranthus caudatus L. (ACA) in plant defending against insect pests, ACA cDNA was cloned by RT-PCR and the 5‘ and 3‘ sequences were confirmed by rapid amplification of cDNA ends (RACE). The phloem-specific expression vector of ACA gene, pBCACAc, was constructed based on the plant binary vector pBC438 and transfered into tobacco plants via Agrobacterium-mediated transformation method. Results from PCR and Southern blotting analysis showed that AOA gene was integrated into the genomes of transformed plants and the transgene integration varied from one to four estimated copies per genome. Western blotting analysis indicated that ACA gene was transcribed and translated in the transgenic plants. The bioassay of Myzus persicae Sulzer on detached leaves demonstrated that the 78% transgenic tobacco plants displayed an average aphid-resistant rate of more than 75%. Some apterous progeny of M. persicae were found dead on the resistant plants. These results indicate that ACA gene should be an effective aphid-resistant gene and could be valuable for application in crop breeding for aphid resistance.     

表达尾穗苋凝集素基因的转基因烟草对桃蚜(Myzus persicae)繁殖的影响

为研究尾穗苋凝集素(ACA)在植物中可能的抗虫作用,通过RH-PCR克隆了ACA cDNA并通过RACE分析证实了cDNA序列的正确性.构建了ACA基因的韧皮部特异表达载体pBCACAc并通过根癌杜菌介导转化了烟草(Nicotiana tabacum L.).PCR和Southern blot分析结果证明,ACA基因已经整合到转化再生植物的基因组中,其插入插贝数1~4个不等.对转基因烟草叶片蛋白时行行免疫反应的结果表明,ACA基因已被转录和翻译.用桃蚜(Myzuspersicae Sulzer)对转基因烟草离体叶片进行了的接虫试验结果表明,测试过的78%的烟草对桃蚜口密度增长的平均抑制率在75%以上,在抗性植株上观察到有桃蚜若虫死亡的现象.以上结果表明,ACA基因是一个有效的抗蚜基因,在作物抗蚜分子育种具有应具应用价值.     

转基因泡桐shiva-1基因遗传与表达分析

在分别获得转基因泡桐自交F-代、杂交F1代的基础上,利用PCR检测所获得的转基因后代群体。结果表明,外源基因在自交子代中分离比例为3：1;杂交子代中分离比例为1：1,符合孟德尔单基因遗传。所获得的无性繁殖子代均能够利用PCR检测到抗菌肽shiva-1基因的存在。RT-PCR证明随机挑选的转基因泡桐子代中shiva-1基因能够转录产生mRNA。     

泡桐丛枝植原体16S rDNA和延伸因子基因序列分析

对采自陕西、山西、甘肃、河南、河北、山东各省的泡桐丛枝病材料,利用巢式扩增,均得到16S rDNA基因片段约1.2kb;扩增得到植原体延伸因子(EF-Tu)tuf基因,长度约为850bp.。通过将16S rDNA基因片段和延伸因子(EF-Tu)tuf基因序列与已知植原体16Sr各组成员进行同源性比较,确定我国大陆泡桐主栽区陕西、山西、甘肃、河南、河北、山东各省与已经报道的台湾省泡桐丛枝植原体基本一致,均为同一个种,没有株系的分化,全部归属于植原体16SrI-D组,从而确定了其分类地位。     

Production and Preliminary Application of Monoclonal Antibodies Against Paulownia Witches' Broom MLO

Monoclonal antibodies against mycoplasma-like organisms (MLO) associated with paulownia witches’broom (PWB) were produced by using partially purified preparations from diseased paulownia. Splenic cells from immunized mice were fused with sp2/0murine myeloma cells. Screened by indirect ELISA using partially purified PWB-MLO and healthy paulownia extracts as detecting antigens, two hybridoma clones that stably secreted specific antibodies against PWB-MLO were obtained from 459 clones of four successful fusions. The monoclonal antibodies were isotyped and determined to be immunoglubin classes IgG2a and IgG3. Antibody titers of ascitic fluids were both over 1.6 × 104 assayed by indirect ELISA. Priliminary application on several specimens proved that they were the monoclonal antibodies against PWB-MLO.     

白花泡桐内生真菌的分离鉴定及抗菌活性筛选

从白花泡桐根、茎、叶中分离出19株内生真菌,对分离出的真菌分别利用琼脂块法和纸片扩散法进行初选和复选,通过形态学特征观察和rRNA基因ITS序列系统发育分析对抗菌活性菌株进行鉴定。抑菌试验结果显示JSD-8、JM-1和JM-10等3株内生真菌对枯草芽胞杆菌(Bacillus subtilis)CGMCC1.769、大肠杆菌(Escherichia coli)CGMCC1.1103和白色念珠菌(Candida albi-cans)ATCC10123均有一定的抗菌活性。鉴定结果表明,JSD-8、JM-1、JM-10分别属于串珠赤霉菌(Gibberella moniliformis)、长柄链格孢菌(Alternaria longipes)和托姆青霉菌(Penicilium thomii)。     

兰考泡桐生物量积累规律的定量研究

对农桐复合经营兰考泡桐的干物质生产、积累和归还规律的系统研究表明,兰考泡桐生物量随树龄增大而增加,生物量在各器官的分配比例依次为：树干＞树枝＞树根＞树叶＞花;兰考泡桐年干物质生产主要集中在５～７月,占全年干物质生产总量的７７．３％;兰考泡桐凋落物绝大部分为落叶,占凋落物总量的８７．１％,凋落伴随年生长季节的全过程,且每年出现两次高峰;兰考泡桐干物质积累主要发生在５～７月,占全年干物质积累总量的７２．７％;兰考泡桐全生育期的干物质归还率为３３．７３％．     

白花泡桐种源的遗传多样性和遗传分化研究

利用ISSR技术对白花泡桐38个种源的遗传多样性和遗传分化进行分析。结果显示：（1）从100个ISSR引物中筛选出9个能扩增出清晰带型并具多态性的引物,共扩增出95个条带,其中88条具多态性,多态位点比率为92.63%。（2）在物种水平上,有效等位基因数（N_e）、Nei’s基因多样性指数（H）、Shannon’s信息指数（I）的平均值分别为1.391 0、0.242 4、0.376 5;种源的多态位点比率在32.63%（江西抚州）~56.84%（广西梧州和江西九江）之间,平均为47.16%;基因流（N_m）为0.912 7,种源间遗传分化系数（G_st）为0.353 9,反映出种源间遗传变异占总遗传变异的35.39%,且遗传变异主要来源于种源内的个体间。（3）遗传一致度在0.39~0.82之间,反映出白花泡桐的遗传基础较宽。UPGMA法聚类分析将38个种源分为3组,主坐标分析(PCoA)将其大致分为4组,两种聚类方法的结果有一定的差异,本文做了相关讨论。研究还表明种源间的遗传距离与地理距离相关不显著。     

Association of a Phytoplasma with Pistachio Witches’ Broom Disease in Iran

Pistachio is an important crop in Iran, which is a major producer and exporter of pistachio nuts. The occurrence of a new disease of pistachio trees, characterized by the development of severe witches’ broom, stunted growth and leaf rosetting, was observed in Ghazvin Province. A phytoplasma was detected in infected trees by polymerase chain reaction (PCR) amplification of rRNA operon sequences. Nested PCR with primer pairs P1/P7 and R16F2n/R16R2 was used for specific detection of the phytoplasma in infected trees. To determine its taxonomy, the random fragment length polymorphism (RFLP) pattern and sequence analysis of the amplified rRNA gene were studied. Sequencing of the amplified products of the phytoplasma 16S rRNA gene indicated that pistachio witches’ broom (PWB) phytoplasma is in a separate 16S rRNA group of phytoplasmas (with sequence homology 97% in Blast search). The unique properties of the DNA of the PWB phytoplasma indicate that it is a representative of a new taxon.     

光周期对泡桐叶片体外植株再生影响研究

以毛泡桐、兰考泡桐和白花泡桐叶片为外植体,在其体外器官直接再生的最适MS和1/2MS培养基上,研究了不同光周期对泡桐叶片体外植株再生的影响.结果表明,光照时间为24 h的光周期可促进泡桐叶片芽的诱导,但不同种泡桐叶片芽诱导率达到最大所需时间存在一定差异.对幼芽根诱导来说,不同光周期对3种泡桐幼芽生根的作用存在差异.当幼芽诱导根时间为7 d时,光照时间长于或短于16 h的光周期都会抑制毛泡桐和兰考泡桐幼芽根的诱导,并且这些不适宜的光周期对白花泡桐和毛泡桐幼芽生根的抑制作用大于兰考泡桐.     

泡桐叶片蛋白质多态性及其聚类分析

研究了9种泡桐叶片蛋白质的多态性,并根据其叶片蛋白质聚丙烯酰胺凝胶单向和双向电泳结果,将它们聚类为白花泡桐组[白花泡桐（Paulownia fortunei）和白花兰泡桐（P.elongata f.allba）]、南方泡桐组[南方泡桐（P.australis )和成都泡桐（P.albiphloea var.chengtuensis)]和毛泡桐组（毛泡桐（P.tomentosa）、川泡桐（P.fargesii）、鄂川泡桐（P.albiphloea）、山明泡桐（P.lamprophylla）和兰考泡桐（P.elon-gata）]。该结果可为了解泡桐属植物的亲缘关系和种的鉴定提供参考依据。     

空桐树的化学成分研究(英文)

从空桐树(Paulownia kawakamii)首次提取分离出7个化合物,经波谱分析和化学反应,分别鉴定为α-lapachone(1)、9-hydroxy-α-lapachone(2)、黄钟花醌(3)、芝麻素(4)、泡桐素(5)、谷甾醇棕榈酸脂(6)和β-谷甾醇(7).     

仙人掌丛枝病植原体CWB1株系16SrRNA基因克隆及序列分析

对表现丛枝症状的仙人掌植株总DNA进行植原体 1 6SrRNA基因PCR扩增 ,得到一条约 1 5kb的特异片段 ,表明植株中有植原体存在 ,将此植原体株系命名为CWB1。把此特异片段与pGEM Teasy载体连接并转化到大肠杆菌JM1 0 9感受态细胞中 ,通过PCR鉴定、限制性内切酶 (EcoRI)酶切分析及核苷酸序列分析 ,均表明克隆成功。序列分析结果显示 ,此株系的 1 6SrRNA基因全长 1 489个碱基 ,与属于植原体 1 6SrⅡ C亚组的Fababeanphyllody植原体同源率最高 ,为 99 7%。通过 1 6SrRNA基因核酸序列同源性比较 ,认为该株系属于 1 6SrⅡ C亚组 ,基本确定了其分类地位。     

高度耐盐双价转基因烟草的研究

随着全球性人口的增长和土地退化的加剧,开发利用广阔盐碱地和干旱土地的需要日益迫切。植物生物技术的日臻完善,为培育高效耐盐植物迎来了一丝曙光。在高渗条件下,耐盐的微生物或植物细胞通过增加胞内一些相溶性溶质的浓度来维持渗透压的平衡。这些可溶性溶质包括无机离子、糖类、多元醇、氨基酸和生物碱等。通过基因工程手段,使细胞内积累脯氮酸⑴、甜菜碱⑵、甘露醇⑶、海藻糖⑷,能够不同程度地提高转基因烟草的耐盐性。多元醇含有多个羟基,亲水性能强,能有效维持细胞内水活度。山梨醇、甘露醇等己糖分子结构、理化性质和生理功能相近。故此．我们认为：不同糖醇在转基因烟草中的积累．可能具有协同(或累加)效应,有希望更大地提高植物耐盐性。我们在获得大肠杆菌mtlD基因(编码l-磷酸甘露醇脱氢酶)和gutD基因(编码6-磷酸山梨醇脱氢酶)克隆⑸的基础上,获得了分别表达mtlD和gutD基因的单价转基因烟草,并首次证实了gucD基因的表达,能显著地提高转基因烟草的耐盐性⑹。本文工作进一步报道同时表达大肠杆菌mtlD和gutD基因双价转基因烟草的高效高度耐盐性。     

Detection of aster yellows phytoplasma in false flax based on PCR and RFLP

False flax (Camelina sativa L.) plants were found to be infected with a yellows-type disease caused by a phytoplasma in experimental plots at the Edmonton Research station. Alberta, Canada. Typical phytoplasmas were detected in the phloem cells in ultrathin sections from leaf midrib tissues examined by electron microscopy. These observations were supported by polymerase chain reaction (PCR) using two primer pairs, R16 F2n/R2 and R16(1)F1/R1, derived from phytoplasma rDNA sequences. Aster yellows (AY) and potato witches'-broom (PWB) phytoplasma DNA samples served as controls and were used to study group relatedness. In a direct PCR assay, DNA amplification with universal primer pair R16F2n/R2 gave the expected PCR products of 1.2 kb. Based on a nested-PCR assay using the latter PCR products as templates, and a specific primer pair, R16(1)F1/R1, designed on the basis of AY phytoplasma rDNA sequences, a PCR product of 1.1 kb was obtained from each phytoplasma-infected false flax and AY sample, but not from PWB phytoplasma and healthy controls. DNA amplification with specific primer pair R16(1)F1/R1 and restriction fragment length polymorphism indicated the presence of AY phytoplasma in the infected false flax sample. This is the first reported characterization of AY phytoplasma in false flax.