以芽孢杆菌作为试验材料,采用硫酸铵分级沉淀、DEAE-52离子交换层析、Sephadex G-100凝胶过滤方法分离纯化β-葡萄糖苷酶,并测定了其部分酶学性质。结果表明:该酶以水杨酸苷为底物时,最适pH值为7.0,最适温度为50℃,是一种中性酶,具有较好的热稳定性。金属离子对酶活性影响较大,其中Fe2+对酶的激活作用最为明显,而K+对酶有明显的抑制作用。 更多还原

Root architecture and anatomical structure of maize cultivars determine the efficiency of nitrogen utilization. It is important to study the differences of root architecture and anatomical structure of different low-N tolerant maize cultivars. 'Xianyu 335' (‘XY335’) and 'Huanong 138' (‘HN138’) were used as experimental materials in this research, and the relationship of root distribution, root activity, root anatomical structure and nitrogen uptake in maize were studied under three nitrogen rates. The results showed that the grain yield, biomass and 1000-grain weight of ‘XY335’ were significantly higher than those of ‘HN138’ under three nitrogen rates. ‘XY335’ had higher root biomass after flowering, and the root-to-shoot ratio was signifcantly higher than that of ‘HN138’ under three nitrogen
treatments. The individual total root length, population root length density, root vigor persistence, nitrogen harvest index and nitrogen use effciency of ‘XY135’ were all signifcantly higher than that of ‘HN138’. Under low nitrogen rates （N180 and N0）, the root activity and the ratio of aeration tissue in root cortex to cross-sectional area of ‘XY335’ increased signifcantly, and the root micro-structure was more reasonable, ensured the higher nitrogen absorption, and
then attained higher grain yield than that of ‘HN138’. Those characters of ‘XY135’ can ensure the nitrogen uptake of plant, and obtain higher nitrogen harvest index and nitrogen use effciency. The results could provide theoretical basis for breeding new maize varieties with high yield, low-N tolerance and high nitrogen use effciency.

The purpose of this paper is to study the effects of exogenous GABA application on the growth,reactive oxygen species(ROS)metabolism,and photosynthesis characteristics of tomato‘Zhongza No.9’seedlings under mixed NaCl and NaHCO₃ stress.The results showed that the plant growth,fresh weight and dry weight were all significantly decreased with the treatment of NaCl and NaHCO₃ stress.At the same time the photosynthesis was inhibited caused by the increasing O2•-production rate and MDA content,though the activities of SOD,POD,and CAT had increased in NaCl and NaHCO₃ treated leaves and roots.It was found that exogenous GABA relieved the harm of mixed NaCl and NaHCO₃ stress,which was manifested by the fact that the fresh weight of the shoot and root were all increased significantly; photosynthetic capacity of seedlings was improved significantly as a result of significant inreasing SOD,POD and CAT activities and decreasing O2•-production rate and MDA content. Exogenous GABA application significantly increased activities of SOD,POD,CAT,but slightly affected the growth,ROS production and photosynthesis characteristics in tomato seedlings under normal nutrient solution.The results indicated that exogenous GABA could increase the resistance of tomato seedlings’growth under mixed NaCl and NaHCO₃ stress by stabilizing the structure and function of cell membrane as well as enhancing the photosynthesis capacity by increasing the antioxidant enzyme activity and reducing the ROS accumulation.

Aiming to investigate the status of soil heavy metal pollution in vegetable fields and the safety of vegetables in North China,and based on the research papers published from 2005 to 2016 of heavy metals concentrations in soil-vegetable in North China,the present study was carried out to explore the soil-vegetable contamination and heavy metal content in vegetables and soils from vegetable fields around North China.Consequently,heavy metal contamination of soils and health risk caused by intaking vegetables were assessed with the Nemerow integrated pollution index method and target hazard quotient.The results showed that the mean concentrations of heavy metals in soil were as follow:Hg 0.212 mg/kg,Zn 91.782 mg/kg,Cu 27.450 mg/kg,Cd 0.514 mg/kg,Cr 69.155 mg/kg,As 9.690 mg/kg,Pb 25.967 mg/kg and Ni 28.786 mg/kg,which were lower than the safety limitation described in farmland environmental quality evaluation standards for edible agricultural products (HJ/T 332—2006).However, heavy metals levels in some soil samples exceeded the safety limitation,accounting for 0.19% (Hg),0.64% (Zn),0.95% (Cu),6.91%(Cd),1.35% (Cr),0.35% (As),1.10% (Pb),and 0.82% Ni),respectively.Moreover,the Cd mean value in vegetable soils from sewage irrigation area was 2.204 mg/kg,which exceeded 2 times of Cd safety limitation in the national standard and the Nemerow Pollution Index reached up to 2.665.It indicated that waste-water irrigated farmlands have been contaminated by Cd severely,whereas the Nemerow Pollution Index was only 0.407 in non-sewage irrigation

The transcription factors categorized into nuclear factor (NF-Y) type play critical roles in mediating
plant tolerance to various abiotic stresses through regulating downstream genes at transcriptional level.In this study,
based on the previous research of TaNF-YB4 which was characterized as a gene of the NF-YB family, we studied
its molecular property, expression patterns upon drought stress, and the effects of genetic transformation on plant
drought adaptation. Results indicated that TaNF-YB4 encodes a protein sharing conserved H4 superfamily domain
together with a nuclear localization motif. Expression analysis revealed that TaNF-YB4 display induced transcripts in both roots and leaves upon drought stressor, with a pattern of elevation over drought stress progression. Compared
with the control (wild type), the tobacco line with TaNF-YB4 overexpression (Sen 1) showed enlarged phenotype,
increased plant biomass, and enhanced leaf area under drought treatment. In contrast, the line with knockdown
expression of TaNF-YB4 (Anti 2) exhibited alleviated growth feature, decreased plant biomass, and reduced leaf
area once challenged with drought. The stomata closure rates in Sen 1 were shown to be promoted whereas those in
Anti 2 to be delayed along with the drought progression. In addition, under drought treatment, the line with TaNFYB4
overexpression showed improved photosynthetic function, contents of soluble protein and soluble sugar, and the
reactive oxygen species (ROS) homestasis-associated parameters. Our investigation suggestes that TaNF-YB4 plays
essential roles in mediating plant drought adaptation due to its regulation for drought-related physiological processes
and biochemical pathways, which improves carbon and nitrogen accumulation, photosynthetic assimilation, and
cellular ROS homeostasis of plants challenged by drought stress.

Large angle fish eye lens are applied in more and more fields.To correct the large-angle fish eye images better,we improve the method that confirms the center and radial of the fisheye images by scanning row by row and column by column,which avoids producing errors when there are many black pixels on the edge of the fish eye images and make the determination of the image center and radial more accurate by threshold judgement which can remove the unreliable edge pixels.Then,we use the algorithm of spherical perspective projection constraint that maps the distorted planar points to the spherical points.After getting the spherical points, these spherical points are mapped to the faces of the cube which circumscribes the sphere.By amplifying the pixels coordinate values of the cube faces properly and using bilinear interpolation on the cube faces,the corrected images are finally achieved.

Guard cells play an important role in the physiology and development of plants.The genetic resources available for Arabidopsisthaliana make it the most favorable plant species for the study of guard cell processes and investigation for genomics and proteomics,but it is difficult to isolate highly purified preparations of large numbers of guard cell protoplasts (GCPs) from this species.In the present report,we described the methods for large-scale isolation of GCPs from Arabidopsis thaliana.It is our hope that the detailed methodologies provided below to establish a set of time-saving,high-efficiency,highly purified,lowcost methodologies. Based on the two-step digestion methods,the protocols require affordable enzymes, raised enzyme concentration and prolonged digestion time to isolate high quality GCPs.The results show the epidermal peels are placed at 22℃ in enzyme solutionⅠfor 1 h, and transferred into enzyme solutionⅡ(2.5% Onozuka R-10 cellulase) for 2 h in darkness, the obtained GCPs are large-quantity and high-purity.

On the basis of books and maps about the military fortresses of the Great Wall in Ming Dynasty,GIS-based cost-surface and the best path,calculated and draw the road map of the military settlement of Datong town,restored the space layout,traffic network and communication station of military settlement,and proved the feasibility of restoring ancient roads with GIS.At the same time,according to the road map,the paper analyzed the defense mechanisms of the Datong town.

More than twenty reduced-height (Rht) (or dwarfing) genes have been designated in wheat by far,however,only few Rht genes were successfully used in wheat breeding programs, thus making the genetic diversity of Rht genes in wheat very narrow.Therefore,it is of great importance to screen and make use of new Rht genetic resources for future necessity of wheat breeding programs.A dwarf wheat mutant (‘Ai 128’) was analyzed in present study with gibberellin treatment,genetic analysis,allelism test and molecular marker assay to determine the nature and putative origin of the Rht gene in ‘Ai 128’.The results showed that the dwarfing mutant is gibberellin-insensitive,and the dwarfing phenotype was controlled by one pair of recessive genes.Allelism test confirmed that the gene conferring the dwarfing trait in ‘Ai 128’ was not allelic to Rht8,Rht9,Rht13,RhtB1b(Rht1),RhtD1b(Rht2),RhtD1c(Rht10) and Rht16,and was also different to Rht4,Rht5,Rht8,Rht9,Rht12 and Rht13,assayed using DNA markers linked with these known Rht genes.Nevertheless,whether the Rht gene in ‘Ai 128’ is a new gene or not needs to be determined by further genetic analysis,such as construction of high-density molecular map using segregant populations derived from crosses of ‘Ai 128’ with other taller-height wheat lines.

In previous research, apathogenesis-related protein gene named TaLr35PR1 was obtained from wheat induced by leaf rust, and its structure characterization and expression profiling was identified. In this study, we predicted the signal peptide and subcellular localization of TaLr35PR1, and then proof it using experiments. The predicted signal peptide was cloned and linked to the trap vector pSUC2T7M130RI, and then transformed to yeast invertase deficient strain YTK12. The results showed that the signal peptide of TaLr35PR1 have the secretion activity. Meanwhile, subcellular location recombination vector pCamA-TaLr35PR1-GFP was constructed using enzyme digestion and ligation. The onion epidermal cells via particle bombardment showed that pCamA-TaLr35PR1-GFP fusion protein not distributed in extracellular environment. These results enriched the research of the pathogenesis-related protein
1gene and provide the basis for the biological function and its mechanism.

Based on the testing,the numerical simulation on concrete freeze-thaw process was analyzed through the ABAQUS finite element analysis software.The influence of different freeze-thaw cycles on various strength grades of concrete was discussed.The frost resistance difference of the concrete with different water cement ratios was also analyzed.The results showed that,the numerical simulation results are consistent with the testing results,indicating that it is feasible to simulate the freeze-thaw cycles of concrete.Besides,the numerical simulation analysis results can testify and explain the testing results,providing guidance for the study of concrete freeze-thaw cycles.

BASIC PENTACYSTEINE (BPC) gene family is a plant-specifific family of transcription factors that plays an important role in the regulation of gene transcription. In order to explore the function and regulation mechanism ofmaize BPC family genes, this study used bioinformatics technology to conduct systematic evolutionary analysis, genestructure analysis, conserved domain analysis, tissue expression characteristics analysis and analysis of expressionlaw in resistance to non-biological genes in maize BPC family genes. It was found that the four BPC family genesof maize all contained conserved GAGA binding domains, which had obvious tissue expression characteristics,and showed different expression rules under heat, cold, salt, UV and drought stress. Real-time PCR technologywas used to detect the expression levels of maize BPC family genes after treatment with different hormones, and itwas found that the expression levels of the four BPC family genes after salicylic acid, jasmonic acid, and ethephon treatment changed signifificantly. The results show that the BPC family genes play an important role in the growthand development of corn and resistance to abiotic stress, which lays a foundation for elucidating the function and regulatory mechanism of maize BPC family genes.

Baoding is a historical and cultural city which is rich in historical and cultural heritage. Also,Baoding Around-the-ancient-city river course is a product which is accompanied by the ancient city.Due to the development of modern cities,the ancient city of Baoding river suffered great damage,leading to the disappearance of its traditional style.By citing the classics and straightening out the history evolution process of Baoding Around-the-ancient-city river course,this article puts forward the river rehabilitation strategies which are based on the fully exploited cultural values,the overall protection of the river and the river landscape amalgamation of the ancient city of Baoding theory.

In recent years,with the rapid development of social economy,the water structure in Hebei Province is changed year by year.Using the water consumption data from 1988to 2012,the change rules of water consumption in agricultural,industrial and domestic sectors were analysed.Results indicated that total water consumption presented a tendency of slight decline,with an annual increasing of 59million m3,of which agricultural water proportion gradually decreased,industrial water proportion and domestic water proportion grew.The reduction of arable areas and the increasing of water-saving irrigated areas were the main reasons of agricultural water consumption reduction.The risen level of repeated utilization ratio of industrial water utilization and the industrial water demand of every increased ten thousand yuan played a positive role in improving the efficiency of industrial water.Population growth was the main factor of the increasing of domestic water consumption.

 

In order to select the optimum biogas organic manure to be used in cucumber growth in solar greenhouse,comparative experiments were conducted for the effects of different types of biogas organic manures and ordinary fertilizers on the yield,disease resistance and quality of cucumbers in this paper.The results showed that both biogas bio-bacterial manure and biogas bio-organic manure improved the plot yield and the yield number per plant significantly, and the effect of biogas bio-bacterial manure was the best,but the effect of biogas organic manure was not significant.Disease occurrence and disease indices of three treatments were lower than that of CK significantly,and the treatment of biogas bio-bacterial manure was the lowest,for which the disease occurrence of downy mildew,powdery mildew,angular leaf spot and anthracnose were 3.89%,6.14%,3.74% and 2.44% respectively;and the disease indices were 2.17,5.34,2.69 and 2.53 respectively.Treatments of biogas bio-bacterial manure and biogas bio-organic manure improved the fruit chlorophyll contents of cucumbers grown in solar greenhouse,and the chlorophyll a contents of the two treatments were higher than that of the biogas organic manure and the control significantly,but the chlorophyll b contents were lower than that of the biogas organic manure and the control significantly.There was no significant difference among water contents of the three treatments and CK.The pH value of the three treatments was lower than that of CK significantly,and the highest pH of CK was 6.84. The fruit firmness of biogas bio-organic manure was the hardest,which were 13.12 for fruits with skin and 12.48 for fruits without skin.The results of subordination function method for the effects of different types of biogas organic manures on the yield,disease resistance and quality of cucumbers are as follows:biogas bio-bacterial manure>biogas bio-organic manure >biogas organic manure>common fertilizer(CK).Thus,the biogas bio-bacterial manure was better than others.

Abstract: The GRAS transcription factors were widely involved in many metabolic pathways of plant growth and development and stress response, which played an important role. The GRAS protein sequences were identified from the whole sorghum genome by using bioinformatics techniques, after removing the redundant sequence by the SMART and PFAM-Search, the analysis of physicochemical property, chromosome location and system evolution were performed by the ExPASy-ProParam, Mapchart, MEGA7.0. The functions of the GRAS genes were annotated through the GO and KEGG. The expression patterns of sorghum GRAS family members in different developing time points of sorghum after uniconazole-treated were analyzed in combination with transcriptomics, and the GRASmembers with significant transcriptome differences were detected by real-time fluorescence quantitative PCR. The results showed that the 80 GRAS transcription factors were identified from the whole genome of sorghum, which were classified into 8 subfamilies according to their genetic relationships. The physico-chemical property showed that the amino acids number of sorghum GRAS genes were between 295 ～ 967, the molecular weights were between 31 529.21 ～ 107 470.03 kD, the average isoelectric point was 6.01. Of which, the 96.25% were unstable proteins, and the average hydrophilia was -0.264. All chromosomes had the GRAS gene distribution except chromosome 7. Based on the analysis of the sorghum transcriptomic data, the GRAS genes could be classified into 5 types by clustering. The 8 differential GRAS genes with significantly different expression levels were selected and verified by qRT-PCR. The results showed that 6 genes were consistent with the expression trend of transcriptomic data, and 5 of them were deferentially expressed by the qRT-PCR. The 5 deferentially expressed genes at different times were screened out from the above results. The study provided a reference for the function of sorghum GRAS transcription factors under the uniconazole treatment.

:Experiment on Baci llus , the β-glucosidase was purified to homogeneity by fractional ammo
nium sulphate precipi tation , ion-exchange chromatog raphy on DEAE-52 and Sephadex G-100 gilfilt
ration chromatog raphy , its properties and subst rate specif icities were studied .The results indicated
that the enzyme exhibited optimum activity at pH 7.0 and 50 ℃, and it' s a neutral enzyme
which kept good stability under the condi tion of hig h temperature .The activity of β-glucosidase w as
st rongly ef fected by metal io ns , enhanced by Fe2 +and inhibited by K+obviously