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Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Leaves, especially the flag leaves, as CHA initial recipients play a decisive role in inducing male sterility. To investigate effects of different treatment times of CHA-SQ-1 used, morphological, biochemical and physiological responses of wheat flag leaves were detected in this study. CHA induced programmed cell death (PCD) as shown in terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) and DNA laddering analysis. In the early phase, CHA-SQ-1 trig-gered organelle changes and PCD in wheat leaves accompanied by excess production of reactive oxygen species (O2 and H2O2) and down-regulation of the activities of superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (POD). Meanwhile, leaf cell DNAs showed ladder-like patterns on agarose gel, indicating that CHA-SQ-1 led to the activation of the responsible endonuclease. The oxidative stress assays showed that lipid peroxidation was strongly activated and photosynthesis was obviously inhibited in SQ-1-induced leaves. However, CHA contents in wheat leaves gradually reduced along with the time CHA-SQ-1 applied. Young flags returned to an oxidative/antioxidative balance and ultimately developed into mature green leaves. These results provide explanation of the relations between PCD and anther abortion and practical application of CHA for hybrid breeding.

Light steel structure with added stories is a economic and effective method of strengthening design for existing buildings, and it is promoted and applied widely. But it still has some problems about computing of seismic action effect. The computing is not simply in accordance with the base shear method. The value of dynamic magnification factor which was counted as ß needs further research. In this paper, the value of is 2 on the basis of theoretical analysis and calculation example. The safety factor of the value is higher, and the design with the ß is more economic and reasonable.

This paper summarized the current research situation and development direction of the storey adding structure all over the country. On the basis of the situation, combined characteristics of light steel storey adding structure, the article analyzed adding structure's damping distribution regularity. Based on the complex damping theory, through the mode-superposition method, there was established the correction formula of the earthquake response spectrum of light steel storey adding structure considered the effects of damping. All above, the article provides the basis for the study on the dynamic properties of light steel storey adding structure.

According to the study of added stories structure form for existing buildings, the basic form and characteristics of existing four added stories structure were analyzed and summarized in this paper. According to the research, light steel structure with added storey as a economic and effective method of strengthening design for existing building, it is promoted and applied widely. But there are some problems in the identification of design standard, the reasonable choice of structure scheme, the calculation of Seismic effect and constitution design to be solved.

This paper deeply analyzes the urban civil system, energy-saving decision-making mechanism, the system components and the related energy-saving anti-adjustment mechanism based on the proposed energy-saving urban civil system's basis. It also presents the classification decision-making and decision-making process for the civil on various components on building systems in decision-making energy-saving features on the system proposed civil heat, urban heating network and the energy saving civil monomer decision making. It also builds the decision support for the city civil agent-based energy-saving system, realizing the basic institutions of the agent to propose the energy-saving urban civil decision.

Through the cracks because of influence of external temperature, and mixed thermal stress in the approximate calculation of the proposed measures to prevent the multi-storey top floor vertical wall cracks, to be prevented in the design, engineering examples by design better buildings products.

为进一步研究杀雄剂SQ-1诱导小麦雄性不育的机制，采用电子克隆的方法分离 TaPDC-E1a 基因，并利用半定量RT-PCR技术分析该基因及其调节酶基因 PDK 和 PDP 的表达特性。结果表明， TaPDC-E1a 基因编码388个氨基酸，具有TPP保守结构域，可能存在2个丝氨酸磷酸化位点；与可育系相比， TaPDC-E1a 基因在生理型不育系和遗传型不育系中表达下调； PDK 基因在生理型不育系中表达下调，而在遗传型不育系中表达上调； PDP 基因在可育系及不育系中的表达趋势无明显变化。表明经杀雄剂SQ-1诱导形成的生理型不育系在败育过程中其能量代谢途径更容易受到影响，推测对 PDK 基因进行调节的上游信号机制在小麦生理型不育系与遗传型不育系中可能不一致。

The objective of this study was to explain the male sterile mechanism of wheat (Triticum aestivum L.) based on chloroplast proteome. A method for isolating intact chloroplast proteome from wheat floret was established. Using this method, the chloroplast proteomes were extracted from florets of the genic and physiological male sterile lines and their maintainer line, and separated in 2-dimensional electrophoresis (2-DE) gels. The cytoplasmic-nuclear sterile line, ms(S)-1376, had identical nuclear background with the maintainer line, (A)-1376, and the physiological male sterile line, ms(A)-1376, was derived from (A)-1376 after induction of chemical hybridizing agent SQ-1. The extraction method was effective to obtain high purity of intact chloroplast using discontinuous sucrose density gradient centrifugation with 3-step gradient densities of 30, 45, and 60%. The 2-DE result showed that the floret chloroplast protein profiles were different among the 3 lines at uninucleate anther stage, and 239 protein spots were visible on each gel (pH 4-7, molecular weight 14.4-66.2 kD). Six differentially expressed proteins were analyzed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) and indexed in bioinformation database. They were identified as acyl-CoA dehydrogenase domain protein, calmodulin-binding protein phosphatase, multiple catalytic peptidase, heat-shock protein 60, light receptor protein 2, and a protein of unknown function. These proteins are involved in series of physiological reactions such as metabolism of energy substances, chloroplast defendance, chloroplasts signal transduction, and plant growth. The differential expressions of these proteins among the 3 lines are likely related to the male sterility in wheat.

To understand the mechanism of male sterility induced by gametocide SQ-1 in wheat (Triticum aestivum L.), TaPDC-E1α gene was isolated using silcon cloning technique. The open reading frame of this gene is 1401 bp in length, putatively encoding 388 amino acid residues. This gene possesses the conserved TPP domains. Two potential phosphorylation sites of serine residues might be present in the TaPDC-E1α protein of wheat. According to semiquantitative reverse transcription polymerase chain reaction (RT-PCR) analysis, the expression levels of TaPDC-E1α in the physiological and genetic male sterile lines were lower than those in the fertile lines. Compared with the fertile lines, the expression of PDK was obviously down-regulated in the physiological male sterile line induced by SQ-1. However, PDK gene was highly expressed in the genetic male sterile lines. The expression levels of PDP gene were similar in the fertile and the male-sterile lines. These results suggest that the pathway of energy metabolism in the SQ-1 induced sterile line is more susceptible than that of the genetic male-sterile line. The upstream signal mechanism of mediating PDK gene may be inconsistent between the male-sterile line induced by SQ-1 and the genetic male-sterile line.

Malondialdehyde (MDA), which is thought to be important inducible factor of cell apoptosis if excessively accumulated in cells, is often regarded as a widely used marker of oxidative lipid injury whose concentration varies in response to biotic and abiotic stress. To elucidate the metabolic mechanism of ROS production and scavenging of the male sterility, normal fertility and male sterility wheat, including genetic and physiologically male sterility, by comparing MDA content and antioxidant enzymes changes in the sterile and fertile leaves, spikes, florets, rachillaes, ovaries and anthers at different developmental anther stages, were employed for studying the relationship between the male sterility and membrane lipid peroxidation, antioxidant enzymes. The results showed that tissue of male sterility had roughly higher content of MDA than corresponding fertile plants, and ovary performance was not obvious but most obvious in anther. Simultaneously, the higher activities of antioxidant enzymes were measured in the anthers of male sterility plant, in which an increase of ROS in anthers of abortion stage had an inducible effect on the antioxidant enzymes. MDA content and scavenging-enzyme activities had difference in the sterile and fertile leaves, spikes, florets, rachillaes at different anther stages, indicating that different tissues of ROS metabolism had noticeable difference in male sterility and normal wheat. It can be considered that the disorder of scavenging-enzyme activities and accumulation of MDA in the male organ, and supplier of nutrition blades were causing a further substance metabolism disorder, energy loss, leading to the occurrence of male sterility. Key words: Wheat - male sterility – malondialdehyde - antioxidant enzymes Abbreviations: CAT---Catalase; CMS---Cytoplasmic male sterility; CHA---Chemical Hybridization Agent; GS---Cytoplasmic male sterile line (S)-1376; MDA---Malondialdehyde; NW---Wheat cultivar 1376; PMS---CHA-SQ-1 induced male sterility wheat; POD---Peroxidase; ROS---Reactive oxygen species; SOD---Superoxide dismutase; SEM---Scanning electronm icroscopy.