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Physiological and Molecular Response of Wheat Roots to Nitrate Supply in Seedling Stage

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Agricultural Sciences in China 2011年第5期10卷 695-704页

作者： WANG ping WANG Zhen-lin CAI Rui-guo LI Yong CHEN Xiao-guang yin yan-ping State Key Laboratory of Crop Biology/Shandong Key Laboratory of Crop Biology/Agronomy College Shandong Agricultural University Tai＇an 271018 P.R.China Agronomy Department Hebei Normal University of Science and Technology Changli 066600 P.R. China

The objective of this study was to understand the morphological,physiological,and molecular responses of wheat roots to nitrate supply at seedling *** wheat genotypes,Jimai 22 and Shannong 15,were grown in Hoagland＇s nutrient solution with different nitrate levels at seedling *** indicated that the plant dry weight and N accumulation increased with the increase of nitrate *** number of axial root,total uptake area （TUA）,and active uptake area （AUA） increased with more nitrate *** analysis indicated that significant positive correlations existed between N accumulation and dry weight,N accumulation and AUA,and N accumulation and AUA/***,the expressions of NRT2.1,NRT2.2,and NRT2.3 decreased with nitrate supply increased,the expressions of NRT1,NRT2.1,and NRT2.3 could maintain high level at N3 *** free amino acid and NO3- content in shoot also increased with the increased nitrate application,but no significant difference was found in root among the *** results implied that the increase of N uptake by nitrate supply was due to the morphological and physiological responses of wheat roots and the high expression level of TaNRT ***,the contribution of morphological,physiological,and molecular parameters was different between two genotypes of wheat.

关键词： wheat root parameters nitrate uptake N metabolites TaNRT expression

Universality Class in Abelian Sandpile Models with Stochastic Toppling Rules

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Communications in Theoretical Physics 2005年第3X期44卷 483-486页

作者： PAN Gui-Jun ZHANG Duan-Ming SUN Hong-Zhang yin yan-ping Department of Physics Huazhong University of Science and Technology Wuhan 430074 China Department of Physics Hubei University Wuhan 430062 China

We present a stochastic critical slope sandpile model, where the amount of grains that fall in an overturning event is stochastic variable. The model is local, conservative, and Abelian. We apply the moment analysis to evaluate critical exponents and finite size scaling method to consistently test the obtained results. Numerical results show that this model, Oslo model, and one-dimensional Abelian Manna model have the same critical behavior although the three models have different stochastic toppling rules, which provides evidences suggesting that Abelian sandpile models with different stochastic toppling rules are in the same universality class.

关键词： self-organized criticality sandpile model universality class

Antioxidant Activity of Pigment Extracted from Green-Wheat-Bran

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Agricultural Sciences in China 2010年第6期9卷 825-832页

作者： TANG Xiao-zhen DONG Yu-xiu WEI Si-qing ZHANG Xian-sheng yin yan-ping Shandong Agricultural University Tai＇an 271018 P.R.China Shandong External Economy Trade Technical School Tai＇an 271000 P.R.China

The anthocyanin pigment extracted from green-wheat-bran was studied to identify its antioxidant *** antioxidant activities of the pigment were evaluated by anti-lipid peroxidation,total antioxidant activity （TAA）,superoxide anion radical scavenging activity （SARSA）,active oxygen scavenging activity （AOSA）,and DPPH （1,1-diphenyl-2 picrylhydrazyl free radical） radical scavenging *** results showed that the pigment had higher antioxidant activity and TAA,SARSA,AOSA and *** activities at a certain concentration than Vc （antiscorbutic vitamin,vitamin C）,and the capacity increased with the increase of pigment *** TAA was 51.06 U mL-1,1.73 times of Vc,and SARSA 18 025.21 U mL-1,2.26% higher than Vc,and AOSA 3 776.31 U mL-1,1.24 times of *** to the *** activity of the pigment,there was a trend that higher concentration performed higher activity significantly improved with the company of *** pigment showed significant antioxidant activities evaluated by different *** will provide a better understanding on antioxidant activity of green wheat and allow the screening or breeding of green wheat varieties with higher antioxidant activity for food processing.

关键词： pigment from green-wheat-bran anti-lipid peroxidation total antioxidant superoxide anion radical scavenging,active oxygen scavenging DPPH.scavenging

Continuous Weight Attack on Complex Network

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Communications in Theoretical Physics 2008年第3期49卷 797-800页

作者： yin yan-ping ZHANG Duan-Ming TAN Jin PAN Gui-Jun HE Min-Hua Department of Physics Huazhong University of Science and Technology Wuhan 430074 China Faculty of Physics and Electronic Technology Hubei University Wuhan 430062 China

We introduce a continuous weight attack strategy and numerically investigate the effect of continuous weight attack strategy on the Barabasi-Albert （BA） scale-free network and the Erdos-Rdnyi （ER） random network. We use a weight coefficient ω to define the attack intensity. The weight coefficient ω increases continuously from 1 to infinity, where 1 represents no attack and infinity represents complete destructive attack. Our results show that the continuous weight attack on two selected nodes with small ω （ω≈ 3） could achieve the same damage of complete elimination of a single selected node on both BA and ER networks. It is found that the continuous weight attack on a single selected edge with small ω （ω≈ 2） can reach the same effect of complete elimination of a single edge on BA network, but on ER network the damage of the continuous weight attack on a single edge is c/ose to but always smaller than that of complete elimination of edge even if ω is very large.

关键词： network efficiency weight coefficient weak attack complex networks

Nitric Oxide Content in Wheat Leaves and Its Relation to Programmed Cell Death of Main Stem and Tillers Under Different Nitrogen Levels

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Journal of Integrative Agriculture 2013年第2期12卷 239-250页

作者： GUO Jun-xiang CHEN Er-ying yin yan-ping WANG ping LI Yong CHEN Xiao-guang WU Guang-lei WANG Zhen-lin National Key Laboratory of Crop Biology Agronomy College Shandong Agricultural University Xuzhou Sweetpotato Research Center/Sweetpotato Research Institute Chinese Academy of Agricultural Sciences

Nitric oxide （NO） is a key signaling molecule in different physiological processes of plants, including programmed cell death （PCD）. PCD of tillers plays an important role in surviving which are major components of grain yield. PCD was triggered in wheat leaves of main stem and tillers by NO content under different nitrogen treatments. In wheat, NO could be synthesized endogenously by nitrate reductase （NR）. As an inducible enzyme, NR activity was closely related to substrate concentration. Therefore, different nitrogen levels would change NR activity and NO production. The objective of this study was to determine the effects of NR activity, NO production, and the correlation between them on different tillers growth, development, senescence, and kernel protein content under different nitrogen levels. Field-experiments were conducted in 2009-2011 growing seasons, using two wheat cultivars with different spike-types. Results showed that for main stem and primary tillers, NR activity and NO content reached high level at heading stage, while for secondary tiller, the level of NR activity was low, but NO content was high in the present research. The NO synthesis depending on NR activity in wheat leaves was significant in the early growing stage, but the NO synthesis weakened with the progress of growing period. NO was related to the senescence of wheat leaves, but PCD was more sensitive to marked changes of NO content than NO content itself. N application had marked influence on the aging process of primary tiller, while had little influence on that of main stem and secondary tiller. Moreover, N fertilizer application could increase spike rate and protein content of primary tiller by N fertilizer application.

关键词： wheat nitric oxide programmed cell death tiller

Foliar application of sodium hydrosulfide(NaHS),a hydrogen sulfide(H2S) donor,can protect seedlings against heat stress in wheat(Triticum aestivum L.)

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Journal of Integrative Agriculture 2016年第12期15卷 2745-2758页

作者： yanG Min QIN Bao-ping MA Xue-li WANG ping LI Mei-ling CHEN Lu-lu CHEN Lei-tai SUN Ai-qing WANG Zhen-lin yin yan-ping State Key Laboratory of Crop Biology/Agronomy College Shandong Agricultural University Tai'an 271018 P.R.China Tai'an Academy of Agricultural Sciences Tai'an 271018 P.R.China

Temperature extremes represent an important limiting factor to plant growth and productivity. Low concentration of hydrogen sulfide （H2S） has been proven to function in physiological responses to various stresses. The present study evaluated the effect of foliar application of wheat seedlings with a H2S donor, sodium hydrosulfide （NariS）, on the response to acute heat stress. The results showed that pretreatment with NariS could promote heat tolerance of wheat seedlings in a dose-depen- dent manner. Again, it was verified that H2S, rather than other sulfur-containing components or sodion derived from NariS solution, should contribute to the positive role in promoting wheat seedlings against heat stress. To further study antioxidant mechanisms of NariS-induced heat tolerance, superoxide dismutase （SOD, EC 1.***.1.1 ）, catalase （CAT, EC 1.***.1.6） and ascorbate peroxidase （APX, EC 1.***.1.11 ） activities, and HzS, hydrogen peroxide （H2O2）, malonaldehyde （MDA）, and soluble sugar contents in wheat seedlings were determined. The results showed that, under heat stress, the activities of SOD, CAT, and APX, H2S, H2O2, MDA, and soluble sugar contents in NaHS-pretreated seedlings and its control all increased. Meanwhile, NaHS-pretreated seedlings showed higher antioxidant enzymes activities and gene expression levels as well as the H2S and soluble sugar levels, and lower H2O2, MDA contents induced by heat stress. While little effect was detected in antioxidant enzymes activities and soluble substances contents in pretreated wheat seedlings compared with its control under normal culture conditions （data not shown）. All of our results suggested that exogenous NariS could alleviate oxidative damage and improve heat tolerance by regulating the antioxidant system in wheat seedlings under heat stress.

关键词： wheat seedlings sodium hydrosulfide heat stress antioxidant system mitigative effect

Exogenous Application of Abscisic Acid or Gibberellin Acid Has Different Effects on Starch Granule Size Distribution in Grains of Wheat

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Journal of Integrative Agriculture 2013年第9期12卷 1551-1559页

作者： PENG Dian-liang CAI Tie yin yan-ping yanG Wei-bing NI ying-li yanG Dong-qing WANG Zhen-lin National Key Laboratory of Crop Biology Shandong Agricultural University

Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and the functionality of wheat products. Two high-yield winter wheat cultivars were used to evaluate the effects of the application of exogenous ABA or GA during the reproductive phase of the initial grain filling on starch granule size distribution and starch components in grains at maturity. The results indicated that a bimodal curve was found in the volume and surface area distribution of grain starch granules, and a unimodal curve was observed for the number distribution under all treatments. The exogenous ABA resulted in a significant increase in the proportions （both by volume and by surface area） of B-type （〈9.9 Ixm in diameter） starch granules, with a reduction in those of A-type （〉9.9 ~tm） starch granules, while, the exogenous GA3 led to converse effects on size distribution of those starch granules. The exogenous ABA also increased starch, amylose and amylopectin contents at maturity but significantly reduced the ratio of amylose to amylopectin. Application of GA3 significantly reduced starch content, amylopectin content but increased the ratio of amylose to amylopectin. The ratio of amylose to amylopectin showed a significant and negative relationship with the volume proportion of granules 〈9.9 μm, but was positively related to the volume proportion of granules 22.8-42.8 μm.

关键词： abscisic acid gibberellin granule size distribution starch winter wheat (Triticum aestivum L.)

Rational surface charge engineering of haloalkane dehalogenase for boosting the enzymatic performance in organic solvent solutions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 276-285页

作者： yin Wu yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Biocatalysis in organic solvents(OSs)has numerous important applications,but native enzymes in OSs often exhibit limited catalytic ***,we proposed a computation-aided surface charge engineering strategy to improve the catalytic performance of haloalkane dehalogenase DhaA in OSs based on the energetic analysis of substrate binding to the DhaA *** variants with enhanced OS resistance were obtained by replacing negative charged residues on the surface with positive charged residue(Arg).Particularly,a four-substitution variant E16R/E93R/E121R/E257R exhibited the best catalytic performance(five-fold improvement in OS resistance and seven-fold half-life increase in 40%(vol)dimethylsulfoxide).As a result,the overall catalytic performance of the variant could be at least 26 times higher than the wild-type *** spectroscopy and molecular dynamics simulation studies revealed that the residue substitution mainly enhanced OS resistance from four aspects:(a)improved the overall structural stability,(b)increased the hydrophobicity of the local microenvironment around the catalytic triad,(c)enriched the hydrophobic substrate around the enzyme molecule,and(d)lowered the contact frequency between OS molecules and the catalytic *** findings validate that computationaided surface charge engineering is an effective and ingenious rational strategy for tailoring enzyme performance in OSs.

关键词： Surface charge engineering Organic solvent resistance Molecular dynamics simulation Haloalkane dehalogenase

Critical Behaviors in a Stochastic One-Dimensional Sand-Pile Model

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Communications in Theoretical Physics 2005年第2X期44卷 316-320页

作者： ZHANG Duan-Ming SUN Hong-Zhang LI Zhi-Hua PAN Gui-Jun YU Bo-Ming yin yan-ping SUN Fan Department of Physics Huazhong University of Science and Technology Wuhan 430074 China Department of Mathematics & Physics Henan University of Science and TechologyLuoyang 471003 China Department of Physics Hubei University Wuhan 430062 China

A one-dimensional sand-pile model (Manna model), which has a stochastic redistribution process, is studied both in discrete and continuous manners. The system evolves into a critical state after a transient period. A detailed analysis of the probability distribution of the avalanche size and duration is numerically investigated. Interestingly,contrary to the deterministic one-dimensional sand-pile model, where multifractal analysis works well, the analysis based on simple finite-size scaling is suited to fitting the data on the distribution of the avalanche size and duration. The exponents characterizing these probability distributions are measured. Scaling relations of these scaling exponents and their universality class are discussed.

关键词： self-organized criticality power-law sand-pile model finite-size scaling universality class