烟草青枯病研究进展

烟草青枯病是由茄青枯雷尔氏菌(Ralstonia solanacearum)引起的影响世界烟草生产的重要病害之一,该病是一种典型的土传性细菌病害。主要对烟草青枯病菌的致病机理、遗传多样性和防治等方面的研究进展进行综述,阐明烟草青枯病菌的研究现状。     

洞庭湖区社鼠脏器重量的比较

对洞庭湖区社鼠(Niviventer confucianus)野外自然种群脏器的重量指标进行了测定,并比较了其在年龄组、性别、季节及生境间的差异。结果表明,社鼠内脏(心、肺、肝、脾、肾脏)随着年龄组的增加,重量有明显的增加,其重量与体重有极其显著的相关性。两性间的脏器重量指标没有显著性差异。脏器季节变化的共同特征是夏季脏器重量较低,四季间比较,仅有心脏重量有显著的季节变化。生境间心脏和肾脏重量的变化相对较大,达显著水平。参与繁殖与未参与繁殖的雌鼠相比,心、肺、肝、肾脏的各项指标均较高,脾脏则相反,但均未有显著性差异。总的来看,洞庭湖社鼠种群的脏器指标相对稳定,尽管重量指标随着年龄组而增加,受性别、季节、生境及繁殖行为的影响相对较小。     

葫芦科蔬菜花粉萌发特性的研究

试验采用花粉离体萌发技术,对葫芦科７属８种蔬菜花粉生活力进行了较为深入的研究,结果表明：葫芦科蔬菜花粉属于“嗜硼、好气、喜温、较耐储藏”的类型。适量的蔗糖可以提高萌发率,并明显有利于花粉管生长。此外,试验中还发现不同种作物花粉萌发力的差异与花粉萌发孔或沟的特征有明显关系联系。     

独根草不同部位几种化学成分的分析比较

为评价独根草这一药赏两用植物,对独根草根、茎和叶中粗灰分、粗纤维、粗脂肪、还原糖、部分矿质元素及活性成分(多糖、绿原酸和总黄酮)进行了测定分析.结果表明:独根草叶中粗灰分、粗纤维、粗蛋白、粗脂肪及还原糖的含量分别为10.11％、8.02％ 、9.54％、9.91％和6.53％;Fe、Zn、Cu、Mn、K、Na、Ca和P等矿质元素含量分别为284、132.8、1.07、19.5μg/g、7.01 mg/g、169.38μg/g、221.9 μg/g和300.5 μg/g;还含有2.00％的绿原酸、6.98％的总黄酮,以及3.29％的粗多糖.叶中各成分含量多高于茎和根,证明其主要药用成分在叶;而茎和根均含有多种元素和活性成分,有一定的药用价值,是一种可以全株入药的药赏两用植物.     

种子小蜂和空壳果实对生物能源树种黄连木果实和油产量的影响(英文)

黄连木Pistacia chinensis Bunge因果实含油量高, 被作为生物能源树种在我国进行大面积栽培推广和能源开发利用。然而, 专性寄生害虫（主要为黄连木广肩小蜂Eurytoma plotnikovi Nikolskaya）的危害及由单性结实和败育所造成的空壳果实可能影响黄连木的果实产量和质量。为了评价种子害虫和空壳果实对黄连木果实产量和质量的影响, 我们测定了河南省济源市3个黄连木种群40株结果雌树的果实产量和油产量, 同时测定了完好果实、 空壳果实和虫蛀果实等3类果实的干重和含油量。结果表明：（1）虫害率和空壳率分别达22.6%和53.0%, 且不同个体和种群间均存在显著差异（P<0.05）。（2）空壳果实（30.7 mg/果）和虫蛀果实（33.1 mg/果）的干重均不到完好果实（67.4 mg/果）的一半; 空壳果实（3.9%）和虫蛀果实（3.8%）的含油量均显著低于完好果实（39.9%）。（3）实测的果实产量（2.9 kg/树）和油产量（0.6 kg/树）分别仅为期望产量的50%（4.7 kg/树）和33%（1.9 kg/树）, 但在3个种群之间无显著差异。本研究显示小蜂危害和空壳果实对黄连木果实产量和质量能造成严重影响, 在将其作为生物能源树种利用时对此应加以克服。     

Enhancer-mediated reporter gene expression in Arabidopsis thaliana: a forward genetic screen

Gene expression is controlled and regulated by interactions between cis-regulatory DNA elements (CREs) and regulatory proteins. Enhancers are one of the most important classes of CREs in eukaryotes. Eukaryotic genes, especially those related to development or responses to environmental cues, are often regulated by multiple enhancers in different tissues and/or at different developmental stages. Remarkably, little is known about the molecular mechanisms by which enhancers regulate gene expression in plants. We identified a distal enhancer, CREβ, which regulates the expression of AtDGK7, which encodes a diacylglycerol kinase in Arabidopsis. We developed a transgenic line containing the luciferase reporter gene (LUC) driven by CREβ fused with a minimal cauliflower mosaic virus (CaMV) 35S promoter. The CREβ enhancer was shown to play a role in the response to osmotic pressure of the LUC reporter gene. A forward genetic screen pipeline based on the transgenic line was established to generate mutations associated with altered expression of the LUC reporter gene. We identified a suite of mutants with variable LUC expression levels as well as different segregation patterns of the mutations in populations. We demonstrate that this pipeline will allow us to identify trans-regulatory factors associated with CREβ function as well as those acting in the regulation of the endogenous AtDGK7 gene.     

Poly ADP-ribose polymerase-1 promotes seed-setting rate by facilitating gametophyte development and meiosis in rice (Oryza sativa L.)

Poly(ADP-ribose) polymerases (PARPs), which transfer either monomer or polymer of ADP-ribose from nicotinamide adenine dinucleotide (NAD⁺) onto target proteins, are required for multiple processes in DNA damage repair, cell cycle, development, and abiotic stress in animals and plants. Here, the uncharacterized rice (Oryza sativa) OsPARP1, which has been predicted to have two alternative OsPARP1 mRNA splicing variants, OsPARP1.1 and OsPARP1.2, was investigated. However, bimolecular fluorescence complementation showed that only OsPARP1.1 interacted with OsPARP3 paralog, suggesting that OsPARP1.1 is a functional protein in rice. OsPARP1 was preferentially expressed in the stamen primordial and pollen grain of mature stamen during flower development. The osparp1 mutant and CRISPR plants were delayed in germination, indicating that defective DNA repair machinery impairs early seed germination. The mutant displayed a normal phenotype during vegetative growth but had a lower seed-setting rate than wild-type plants under normal conditions. Chromosome bridges and DNA fragmentations were detected in male meiocytes at anaphase I to prophase II. After meiosis II, malformed tetrads or tetrads with micronuclei were formed. Meanwhile, the abnormality was also found in embryo sac development. Collectively, these results suggest that OsPARP1 plays an important role in mediating response to DNA damage and gametophyte development, crucial for rice yield in the natural environment.     

Molecular characterization,tissue expression profile and SNP analysis of the porcine NR1H4 gene

Nuclear Receptor subfamily 1, group H, member 4 (NR1H4) is a receptor for bile acids and has an important role in regulating energy metabolism in liver, muscle and adipose tissues in humans and animals. In this study, we cloned the full coding region of NR1H4 gene from porcine Longissimus dorsi by Rapid amplification of cDNA end (RACE). Results indicated that the open reading frame of NR1H4 covered 1461 bp encoding 486 amino acid residues and the deduced amino acid sequence was 91–94 % identical to that of Homo sapiens, Bos taurus, Macaca mulatta, Gorilla gorilla, and Ovis aries. Bioinformatic analysis indicated that NR1H4 contained 31 phosphorylation sites with 14 serine, 6 threonine and 11 tyrosine. One single nucleotide polymorphism (SNP) was detected by PCR–RFLP in 3′ untranslated region of exon 9 (NR1H4) and the allele frequency analysis showed that A allele frequency was low among 396 pigs from five breeds. The NR1H4 mRNA expression pattern showed that NR1H4 gene was expressed highly in live and Longissimus dorsi. This work provided an important experimental basis for further research on mechanism of lipid metabolism and fat deposition in pigs.     

莽山浪畔湖国家重要湿地植物多样性及环境解释

研究莽山高山湖泊湿地植物多样性对环境因子的响应分析,不仅有助于深入了解湿地植物对环境变化下的适应策略,同时对保护当地湿地珍稀濒危物种具有重要价值。采用系统聚类分析、典范对应分析(CCA)和Pearson相关性分析等方法,对研究区30个植物群落样方进行分析,研究植物多样性与环境因子(土壤、水)之间的相互关系。研究结果表明:浪畔湖国家重要湿地植物群落可分为蕨状苔草+宽叶泽苔草群丛、雪白睡莲+莼菜群丛、水毛花+宽叶泽苔草群丛、莼菜+宽叶泽苔草群丛等4类。雪白睡莲+莼菜群丛Patrick丰富度指数和Pielou均匀度指数最低,Simpson多样性指数最高,水毛花+宽叶泽苔草群丛与之相反。浪畔湖国家重要湿地植物多样性与土壤速效钾和水深呈极显著相关性,与水质氨氮呈显著相关性,水深和土壤速效钾是影响湿地植物群落分布格局的主要因子。群落物种多样性指数与环境因子之间存在显著相关性,群落物种丰富度指数随水深增加呈先增后降的趋势,群落物种均匀度指数与水质氨氮浓度之间呈负相关关系。本研究旨在揭示浪畔湖国家重要湿地植物多样性与环境因子之间的生态关系,为保护湿地珍稀物种及维持湿地生态系统稳定提供理论依据。