Table of Content

15 April 2017, Volume 19 Issue 4

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Bibliometrics Evaluation on Anaerobic Digestion Technology of Straw

WANG Yang

2017, 19(4):  1-9.  DOI: 10.13304/j.nykjdb.2016.454

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Straw is an important natural resource which can be reused by anaerobic digestion technology. It can not only produce clean energy, but also reduce the environment pollution of rural and urban. This article analyzed status and trends of straw anaerobic digestion in the world based on bibliometrics. Issues including major institutions, international cooperation, status, trends and frontiers were analyzed. These co-countries maps and keywords clustering analysis could reveal co-countries and hotspots in this field. These results could  help the researchers get an overview of this field quickly and accurately.


Research on Insecticidal Activity of  cry2Ah-M Gene

LI Qin1,2, CHEN Quanjia1, MENG Zhigang2, ZHANG Rui2, LIANG Chengzhen2,

2017, 19(4):  10-16.  DOI: 10.13304/j.nykjdb.2016.252

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Transgenic Bt cotton has gained great ecological and economic benefits after application in research and production for over 20 a, but the resistance risk of cotton boll worm is also increasing gradually. Therefore, exploration of Bt genes by different insecticidal mechanism can not only improve insecticidal efficiency, but also avoid or delay insect resistance effectively. Based on preference of cotton genetic codon, this study  optimized the codon of new Bt gene cry2Ah-like from Bacillus thuringiensis (Bt), constructed plant expression vector, and introduced into tobacco mediated by agro-bacterium. The fact of foreign gene in transgenic tobacco was expressed steadily, RNA was proven and protein level had already been integrated into tobacco genome. The results of biological activity detection showed that after feeding 4 d with transgenic tobacco leaves, the corrected mortality of cotton boll worm can be 8659% and achieving high resistance level. This result further proved that cry2Ah-M gene after codon optimization can express effective and with higher insecticidal activity, and was a new gene for effective prevention of cotton boll worm.

 

Effect of NaCl Stress on the Content of K⁺, Na⁺ and Cl^- and the Growth of Sweet Potato Plants

ZHOU Zhilin1,2, TANG Jun1, CAO Qinghe1, ZHAO Donglan1, ZHANG An1

2017, 19(4):  17-23. 

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This paper investigated the contents of K⁺, Na⁺ and Cl^-  and growth status of sweet potato plant with different gene type under NaCl treatment, so as to discuss the effect of K⁺, Na⁺ and Cl^- content changes in different organs  on plant growth and provide basis for identification of salt tolerant materials and studies on salt tolerant mechanism. Taking Shangshu19 as CK, T06 and T11 mutation by EMS  as material, this experiment  analyzed the K⁺, Na⁺ and Cl^-  contents changes in sweet potato root,stem and leaves under NaCl stress and their relation with sweet potato plant growth. The results showed that with the NaCl treatment time prolonging, the dry weight and the ratio of K⁺/Na⁺ of root，stem and leaf in all materials were decreased, while the content of Na⁺、K⁺、Cl^-was gradually increased. But T06 and T11 kept the higher dry weight increasing rate and K⁺ content and K⁺、Na⁺ value, and lower Na⁺ and Cl^- content than that of the CK. There were nagatively significant and extreme significant  correlation between the content of Na⁺ and Cl^- in plant, while the correlation with K⁺ content was significant positively. So the NaCl treatment could keep  higher plant growth rate，lower Cl^- and Na⁺ contents，higher K⁺/Na⁺ value. These indicators could provide reference for salt tolerance identification.

Studies on Effects of Different Conditions on Induction Rate of Hairy Roots in Cucumis sativus L.

JIANG Jinglong1, JIANG Chao1, LI Li2, SHEN Jixue1, TIAN Yun1, REN Xuming1

2017, 19(4):  24-30.  DOI: 10.13304/j.nykjdb.2016.581

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Taking 3 cultivars of cucumber “Jinyan 4”, “Xinjinchun 4” and “Yujiaolong” as experimental material, this study compared different conditions affecting induction rate of hairy root and comprehensively evaluated the induction abilities of hairy roots with A. rhizogenes (A4) among these 3 cucumber cultivers by the method of subordinate function. These studies would provide a high-efficiency system for the induction of agrobacterium rhizogenes in cucumber. Results showed that hairy roots were successfully induced in 3 cucumber cultivars, and they could grow normally after transferred. Analysis of different conditions showed that selections the stem with leaf as explant, 10 minutes as infection time, OD600=0.3 as microbial concentration and 10 mg/L as concentration of acetosyringone (As) were the optimized experiment conditions for induction rate of hairy roots. The order of induction ability on hair roots was “Yujiaolong”>“Jinyan 4”>“Xinjinchun 4” in these 3 cultivars of cucumber by subordinate function. It demonstrated that T-DNA on Ri plasmid of A4 had been integrated into the genome of nuclear cucumber genome successfully through molecular identification by PCR.


Potassium Accumulation and Root Physiological Characteristics of AtNHX1-expressing Tobacco

XU Jie1, WU Hengyan1, XUE Gang1, CHEN Rongping2, PENG Yufu3, HAN Zhujun1, XU Shixiao1, YANG Tiezhao1*

2017, 19(4):  31-37.  DOI: 10.13304/j.nykjdb.2016.654

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In order to investigate the physilogical reason for potassium content increasing in leaves of AtNHX1 tobacco,  using positive AtNHX1 gene homozygous strain N7, N9, N10 and non-transgenic control K326 as material under field and hydroponic condition, this paper studied the potassium content, root system morphology and physiological characteristics of AtNHX1-expressing tobacco lines. The results showed that AtNHX1-expressing tobacco lines grew with unanimous vigor in the fields. The potassium content on leaves at 10~70 d was remarkably higher than that of the control under filed condition. In hydroponic experiment, the AtNHX1-expressing tobacco lines exhibited strong potassium absorption capability and larger maximum potassium absorption rate. The root system morphology and vigor, cation exchange capacity and ATPase activity were significantly higher than that of the control. These results indicated that AtNHX1-expressing tobacco lines had  effective potassium absorption and accumulation characteristics. Therefore, the potassium content in tobacco leaf was greatly increased.


The Effects of MeJA and CS Mixture on Seed Germination of Bupleurum Chinense DC.

MA Yanzhi

2017, 19(4):  38-44.  DOI: 10.13304/j.nykjdb.2016.582

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In order to  promot seed germination of Buplerurum chinense DC in field cultivation, the seeds were used as materials and soaked in mixed liquor with different ratio of CS and MeJA for 24 h. Seeds soaked in pure water were taken as the CK. Then moisture content, volum, germination rate, soluble sugar and soluble protein contents, and free amino acids contents of the seeds were measured and analyzed. The results showed that all MeJA and CS mixed liquor could promote seed germination rate. At 35 d,  the germination rates of all treatments were significantly higher than that of the CK. The germination rates of all treatments were higher than the CK significantly. But there was no significant difference between T3 and T4, and there was significant difference between them and the other treatments. The relative maximum change rate of moisture content of T2 was the biggest, and that of T3 and the CK were the least. Except T3 and the CK, there were significant differences among the other treatments. The volume of all treatments showed first down and then up trend. T4 had the biggest volume. The total soluble sugar content showed down-up-down-up wave change trend. During seed germination process, the overall soluble protein contents showed decreasing tendency. After 35 d, the amino acid contents of the CK and T3 were higher than before, while that of T1, T2 and T4 were lower than the initial stage. Comprehensive evaluation by subordination function analysis showed that soaking seed with the mixture of 10 mg/mL CS and 224.3 μg/mL MeJA had the best effect. The germination rate could reach 54%. These results provided reference for promoting seed germination in aritificial cultivation of Bupleum chinense.

Progress on the Influence of  Translation Rate on the Expression of Recombinant Proteins

CHANG Meihui, CHU Xiaoyu*, WU Ningfeng

2017, 19(4):  45-50.  DOI: 10.13304/j.nykjdb.2016.483

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Using genetic engineering technology to express and obtain high-yield recombinant proteins plays an important role in the development of modern biology and application. Studies have found that heterologous expression of original genes was very difficult. After the expression system was modified, such as optimizing of promoter, signal peptide and increasing gene copies, the quantity of recombinant protein expression was still very low. Therefore, exploring new way to increase the gene expression is a hot research topic. In order to get more effective strategies to increase recombinant protein expression level,  this article comprehensively narrated the effected on the translation rate of protein based on the translation initiation area, codon preferences, mRNA secondary structure and SD-like sequence.

Development and Application of the Safe Production and Quality Traceability System for Vegetable

QIU Rongzhou 1, CHI Meixiang1, CHEN Hong2, WENG Qiyong3, ZHAO Jian2*

2017, 19(4):  51-58.  DOI: 10.13304/j.nykjdb.2016.402

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Vegetable is an important agricultural product in China. Its quality and safety has been a focus of social concern, since it is related to the national interest and people’s livelihood. The quality and safety problems still exist in vegetable products. The source and destination of unqualified vegetables are unknown and responsibility is unclear. The enterprises lack effective information management means for managing vegetable production base. There is no effective pathway for consumers to get reliable information about their bought vegetables. Therefore, this paper developed a system with trace-ability technology for managing vegetable production base, introducing in detail the design of traceability code, system development environment, business process and main function with emphasis on expounding how to guide vegetable safety management mode by regulation control. The development and application of this system helped the enterprises producing unqualified vegetables to realize internal trace-ability; and the consumers to inquire vegetables trace-ability information through smart phone. This paper provided information tools for vegetable producing enterprises to control the quality and manage the production base. Thus, it also provided a trace-ability system to the government for solving all quality problems.

Detection System of Chlorophyll Content of Cyclobalanopsis glauca Using Image Processing Technology

WANG Yi, YAN Zhiyong*

2017, 19(4):  59-64.  DOI: 10.13304/j.nykjdb.2016.424

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In order to obtain plant chlorophyll content in real time, by convenient and economic way, this paper studied the real-time detection system for cyclobalanopsis glauca chlorophyll content based on machine vision library OPENCV. Firstly, blade image was acquired through a digital camera, image R, G, B value was obtained after dealing with threshold segmentation, noise processing and image traversal. Then, different image color characteristic parameters were got from a variety changes combination of image R, G, B. The correlation of image color feature parameters and chlorophyll content of cyclobalanopsis glauca were analyzed, and high correlation coefficient of leaf image color characteristic parameters and chlorophyll content were analyzed through fitting analysis. The results showed that the image feature parameters R, R-B, (R-B)/(R+B) were very significantly correlated. Based on that, the chlorophyll content detection model was established. In addition, the detecting system was written by C++, OPENCV and QT4. Finally, the system detecting results were compared with that by the other methods; average error of system detecting result was found out to be 7.19%; and maximum error was 12.65%, proving the validity and accuracy of this system.


Drought Resistance Evaluation of Main Millet Cultivars  in Zhangjiakou During Germination

ZHANG Jinling, ZHANG Yanyang, ZHANG Ye, PENG Yuan, WANG Junhuan, SONG Jinhui*, LIU Yan

2017, 19(4):  65-72.  DOI: 10.13304/j.nykjdb.2016.769

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In order to evaluate the drought resistance of main cultivated millet varieties during seed germination stage, germination rate，germination energy，germination index，sprout length and sprout fresh weight were measured under drought stress simulated with different concentrations of PEG-6000 (0, 5%, 10%, 15%, 20% and 25%). The results showed: ①under non-stress condition (CK), germination characteristics of 8 millet varieties was different and seed germinating period of conventional millet varieties was shorter than hybrid millet varieties, ②the low consistence PEG-6000 could improve seed germination rate and germination energy of some millet varieties, but with the concentration  increased, the inhibitory also increased, five indexes decreased with increasing concentration of PEG-6000. Using fuzzy membership function method. The comprehensive evaluation of drought resistance of 8 millet varieties,  indicated that Zhangzagu 5 and Zhangzagu 3 showed the highest and the lowest drought resistances respectively during seed germination period.


Combined Effects of Bamboo Biochar and T20 Amendment on Dryland Flue-cured Tobacco Ecology, Yield and Quality at South Anhui Province

PAN Jinhua1, ZHUANG Shunyao1*, SHI Xuezheng1, CAO Zhihong1, CAI Xianjie2, CHENG Sen2

2017, 19(4):  73-81.  DOI: 10.13304/j.nykjdb.2016.408

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In order to explore the combined effects of bamboo biochar and T20 combination amendment on dryland flue-cured tobacco ecology, yield and quality at south Anhui province, this paper studied the effects of indicators of 3 different bamboo biochar amounts and T20 combination amendment  on agronomic characteristics, SPAD value, economic characters, appearance quality, smoking quality and inner chemical component of flue-cured tobacco. Results showed that the combined application of bamboo biochar and T20 could stimulate flue-cured tobacco growth and development, be beneficial for “early germination and fast growing” of flue-cured tobacco. It showed remarkable advantages especially at vigorous growing and maturing stages. During tobacco resetting and vigorous growing stages. The SPAD values of A1 and A2 adding bamboo biochar and T20 treatments were significantly higher than that of the control. The combination of bamboo biochar and T20 could increase tobacco leaf yield and optimize grading structure. The A1, A2 and A3 treatments increased the tobacco yield by 7.02%, 7.31% and 23.28%, respectively, as compared with the control. At the same time, the combination had improved the appearance and smoke panel test quality of the flue-cured tobacco. As for inner chemical components and coordination, this combination reduced the contents of nicotine, total nitrogen and protein, but the contents of reductive sugar and potassium did not increase significantly. The same situation was the nitrogen-nicotine and potassium-chlorine ratios. Results indicated the compound of bamboo biochar and T20 could improve the growth of dryland flue-cured tobacco at south Anhui province, increse its economic character and coordinate its inner chemical quality. These results also provided theoretical basis and referrences for the application of charcoal and inorganic mineral material in dryland agriculture production.

Effects of Different Soil Amendments on Soil Chemical Properties and Soil Enzyme Activities of Continuous Cropping Tobacco

WANG Peiwen1, ZHU Jinfeng2, REN Zhiguang1, CHEN Zheng1, XU Zicheng1*

2017, 19(4):  82-91.  DOI: 10.13304/j.nykjdb.2016.415

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In order to study the effects of different soil amendments on soil chemical properties and soil enzyme activities in continuous cropping tobacco cultivation, and relationship between soil enzymes and soil chemical properties, this experiment collected and analyzed the tobacco rhizosphere soil at 30 d, 50 d, 70 d and 90 d after transplantion, discussed the relationship between soil chemical properties and soil enzyme activity by combining simple correlation analysis, canonical correlation analysis and factor analysis. The results showed that wormcast and microbial fertilizer could significantly improve the soil quality in continuous cropping tobacco cultivation and increase soil nutrient contents, and soil enzyme activity. There was a strong correlation between soil chemical properties and soil enzyme activities. Results of canonical correlation analysis showed that the soil environmental factors, which had the most significant effects on soil fertility, were urease activity and content of alkali solution nitrogen. The content of nitrogen in soil for continuous cropping tobacco cultivation was the key factor affecting soil quality. The results of factor analysis showed that urease, phosphatase, alkaline hydrolysis nitrogen, catalase and available potassium 5 indexes could be used for certain extent to characterize soil fertility, which was higher load on the first principal component. Soil enzyme activities and soil chemical properties could be used commonly to evaluate the level of soil comprehensive fertility.

Studies on Preparation and Evaluation Method of Several Polymeric Materials Coated Urea

XUE Hailong1,2, XU Wennian1,2,3, LIU Daxiang2,3*, XIA Zhenyao2,3

2017, 19(4):  92-99.  DOI: 10.13304/j.nykjdb.2016.624

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In order to investigate the urea nutrient releasing characteristics, this paper took organic material (starch A/ polyvinyl alcohol V) as substrate material, inorganic non-metallic mineral (diatomite G/ bentonite P/ zeolite powder F) as modified material to prepare composite material and coated urea, and measured granulation rate and compressive strength by water dissolution rate and soil incubation methods. Besides, the paper also probed into the nutrient release rule of coated fertilizer, and compared  the testing results of these 2 methods. The results showed that grain yield difference was significant in each particle size of coated urea, the granulation effect was the best in particle size 3~4 mm of the 3 kinds of coated urea, which was about 60%. The granulation effect and compressive strength all expressed AVGU>AVPU>AVFU, indicating the adhesive property was AVG>AVP>AVF. The nutrient release rate of coated fertilizer in soil and water and release duration were different. The initial dissolution rate of AVFU in water was as high as 30%, cumulative release rate of 7 d was as high as 75.02%, release duration was only about 11 d. Slow release performance of AVGU and AVPU nitrogen were significant. The initial dissolution rate was only about 12%~15%, the cumulative release rate of 7 d was 42.24%~58.36%, release  duration was about 36~44 d.  At the same time, the dissolution rate of soil nutrients was only 26%~57%, but the release duration was increased to 42~112 d. On the basis of polyvinyl alcohol starch polymer, the water resistance and slow release effect of the membrane material could be optimized by adding modifier. The water absorption character of film material was very good for ensuring the slow release of fertilizer nutrients, and preferably  providing nutrients for plant growth.

Repellent Effect of Adult Serica orientalis (Motschulsky) Homogenates on Its Adult

MENG Tingling§, MEN Lina§, WANG Zheng, WANG Yuanmin, BAI Shubing, QIAO Jingjing, LIU Xianqian, JI Weirong, ZHANG Zhiwei*

2017, 19(4):  100-109.  DOI: 10.13304/j.nykjdb.2016.606

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Serica orientalis (Motschulsky) is an important forest defoliator of various hosts, and a serious threat to economically important species of fruit and ornamental trees, like apple, nut and winged spindle tree, etc.. In order to explore economically and environmental friendly behavioral control technology, this paper studied on the repellency of S. orientalis adult homogenates among 4 different host plants [Euonymus alatus (Thunb.) Sieb, Malus pumila Mill.,  Populus nigra var. thevestina (Dode) Bean, Pyrus bretschneideri Rehd.]  using a Y-tube olfactometer. The results showed that there were no significant differences (P>0.05) in response rates to different hosts between male and female adults; neither between attractant rates and repellent rates of different hosts to male and female adults. Both male and female S. orientalis displayed similar and highly significant positive tropism to Euonymus alatus, Pyrus bretschneideri and Malus pumila relative to blank controls (P<0.01). While there were no significant differences (P>0.05) in the attraction and repulsion of S. orientalis to these trees in pairwise comparisons. Application of S. orientalis adult homogenates on the 4 species of host plants′ young branches and leaves resulted in highly significant negative taxis (P<0.01) of S. orientalis to those young branches and leaves, and the number of adults that were non-selective for any host plant was higher than 40%. These results provided a behavioral basis for using these homogenates as repellents in agricultural and forestry production.

Feasibility Study on Desalted Sea Sand Used as Soilless Culture Substrates in the South China Sea Islands

MU Dawei1,2,3, SUN Li1, JIANG Xuefei4, WANG Lei4, AI Tengteng5, WANG Lanying6

2017, 19(4):  110-118.  DOI: 10.13304/j.nykjdb.2016.509

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Peat and rock wool needed frequent replacement, so it were not suitable as substrates in soilless culture for the South China sea islands because of the higher transportation costs. Sea sand, as local materials, was easy to draw and could be used as better substrates in soilless culture. There was no studies on using desalted sea sand as culture substrates in China. In order to clarify its feasibility, this experiment took 3∶1 coconut chaff and vermiculite mixed-substrates as the CK and treated desalted sea sand(T) to cultivate lettuce, and analyzed the morphological index, yield, nutritional quality and food safety indexes of lettuce. The result showed that: ① The yield of lettuce commercial products and total dry weight cultured in T were 14.93% and 49.73% higher than the CK, respectively. ② The soluble sugar content of lettuce cultured in T was 2.47% higher than the CK（0.37%）, while the nitrate nitrogen content was 1.77 mg/g lower than the CK（12.67 mg/g）. The differences were extremely significant（P＜0.01）. The differences in soluble protein and vitamin C contents of lettuce cultured in T were not significant with that of the CK. ③ There were no obvious differences in Ca, Fe, Mg, Zn contents between lettuce cultivated in T and the CK. The As and Cd contents of lettuce cultivated in T and the CK were all accord with the national standard. These results indicated that yield of lettuce cultivated in desalted sea sand was normal. Its nutritional quality was good and food safety was OK. It was feasible to use desalted sea sand as substrates in soilless cultivation.

Extraction and Anti-microbial Activities of Anthocyanins from Longling Dendrobium candidum

LI Xiaojiao, YAN Aifen, YANG Lihua, HE Jianmin, HOU Hongbo*

2017, 19(4):  119-127.  DOI: 10.13304/j.nykjdb.2016.449

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Taking Dendrobium candidum in Longling County of Yunnan Province as experimental material, this study obtained anthocyanins with solvent-extraction method. The effects of ethanol volume fraction, material-liquid ratio, extraction temperature, pH, extraction time on the extraction rate of anthocyanins were studied by single fator experiment; and the best extraction technology condition was obtained through technology optimization by orthogonality experimental method. Besides, bacteriostasic activities of anthocyanins from Dendrobium candidum inhibiting Escherichia coli, Staphyloccocus aureus, Bacillus subtilis were also studied. Results showed that the optimal condition were as following: ethanol 60%, material-liquid ratio 1 g∶20 mL, extraction temperature 4℃, pH 3, extraction time 120 min, twice extraction time, and the total anthocyanins yield 3.12 mg/g FW. The minimum inhibitory mass concentration(MIC) on Escherichia coli, Staphyloccocus aureus, Bacillus subtilis were 9.75 mg/L, 4.88 mg/L and 1.22 mg/L, respectively. And the minimum bactericidal concentration(MBC) were 9.75 mg/L, 4.88 mg/L, 2.44 mg/L, respectively.

Preparation of Tobacco Chlorogenic Acid Nanoliposome and Its Stability Analysis

HU Ruirui1,2, SHEN Guoming1*, GAO Lin1, ZHANG Xiaoming3, XIA Shuqin3, CHENG Changhe4, LI Liqun5, WANG Yingqi6, WANG Shujian6

2017, 19(4):  128-137.  DOI: 10.13304/j.nykjdb.2016.621

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This paper screened 3 preparation methods of tobacco chlorogenic acid (CA) nanoliposome, and analyzed their stability. Dialysis method was employed to determine entrapment efficiency (EE) of chlorogenic acid liposomes. Thin film hydration, reverse phase evaporation technique, and ethyl alcohol injection methods were screened based on EE and diameter of liposomes. The effects of film (lecithin+cholesterol)/CA mass ratio, lecithin/cholesterol mass ratio and ultrasonication time on EE and effective loading ability of liposomes were investigated. Orthogonal combination design was used to determine the best process parameters. Finally, the stability of the prepared liposomes was evaluated. The results showed that when film/CA mass ratio was 9∶1, lecithin/cholesterol mass ratio was 4∶1 and ultrasonication time was 5 min, the CA nanoliposomes showed regular spherical. Its average grain diameter was 77.16 nm with good dispersibility. The embedding rate and efficient loading capacity could be up to 88.02% and 9.69%, respectively. Post-embedding liposome thermal and alkaline stabilities were all improved. UV test showed that CA was encapsulated successfully into nanoliposomes. Above results showed that CA nanoliposomes prepared by ethyl alcohol injection method had small grain diameter, good dispersion, better thermal stability, alkaline stability and storage stability.