Wide compatibility in rice (Oryza sativa L.)

Summary Wide compatible varieties (WCVs) show normal spikelet fertility in crosses with Indica and Japonica rice varieties. Crosses of Indica and Japonica varieties frequently show high spikelet sterility which prevents exploitation of heterosis for grain yield. We screened 41 rice varieties for the wide compatibility trait by crossing each with three Indica and three Japonica testers. Varieties giving fertile F₁ hybrids with both groups of testers were classified as WCVs. Seven varieties viz., BPI-76 (Indica); N 22; Lambayeque-1 and Dular (Aus); Moroberekan, Palawan and Fossa HV (Japonicas), were identified as WCVs. The frequency of WCVs was higher among Aus and Japonicas. The wide compatibility trait in varieties: Dular and Moroberekan was controlled by a single dominant gene linked with the Est-2 and Amp-3 loci (mean recombination 32.0%). Est-2 and Amp-3 showed complete linkage. Pgi-2 was found to be linked with Est-2 and Amp-3 (mean recombination 16.1%). Est-2 and Amp-3, showed a tighter linkage with C ⁺ (mean recombination 4.1%). Pgi-2 showed a lower linkage with C ⁺ (mean recombination 17.3%). The recombination values between the WC gene in Dular and C ⁺ was much higher than those reported in Japan for the WC gene (S₅ ⁿ) from Ketan Nangka. It is possible that the WC gene from Dular is different from that in Ketan Nangka. Linkage intensities with the WC gene were not strong enough to be of use for indirect selection for the wide compatibility trait. A search for a more closely linked isozyme or DNA marker was proposed.     

小麦宽幅匀播技术氮、磷、钾施肥效果及推荐施肥量研究

为了探讨宽幅匀播小麦的肥料高效利用和土壤养分吸收的机理,采用多点田间小区试验,应用“3414”田间肥料试验设计方法,分析在不同肥力水平下小麦宽幅匀播技术氮、磷、钾的施肥效果和推荐用量。结果得出,宽幅匀播小麦氮、磷、钾养分利用率随施肥水平提高而显著降低,随土壤肥力增加呈先增高后降低,从高到低依次为：中肥力＞较低肥力＞低肥力＞较高肥力＞高肥力。随土壤肥力由低到高增加,宽幅匀播小麦最佳施肥效益的推荐施肥量分别是N 107.9~171.8 kg/hm²、P₂O₅ 88.2~112.1 kg/hm²和K₂O 35.4~56.2 kg/hm²,平均分别为：N 138.3 kg/hm²、P₂O₅ 101.4 kg/hm²、K₂O 45.4 kg/hm²,三要素比例为N:P₂O₅:K₂O=1:0.73:0.33。由于不同土壤类型的速效氮磷钾含量有一定差异,小麦宽幅匀播适宜施肥量应因土壤类型而适当调整。     

Wide hybridization between wheat (Triticum L.) and lymegrass (Leymus Hochst.)

A total of 240 F₁ hybrids was made beween wheat (Triticum aestivum L. em. Thell. (2n = 6x = 42) and T. carthlicum Nevski (2n = 4x = 28)) and perennial lymegrass (North European Leymus arenarius (L.) Hochst. (2n = 8x = 56) and North American L. mollis (Trin.) Pilger (2n = 4x = 28)). The wide crosses yielded embryos in 20% of caryopses and 96% of the embryos developed into normal hybrid plants. The hybrids were vegetatively vigorous, with evidence of the Leymus rhizomatous habit. Those deriving from L. arenarius survived overwintering in Iceland, but the hybrids L. mollis did not, whereas in a milder environment, both showed perenniality. Cytogenetic analysis of root tip cells before the plants were treated with colchicine showed that 21 out of 28 hybrids investigated had chromosome mosaics, with a population of both amphihaploid and amphidiploid cells. This spontaneous doubling of somatic chromosomes occurred in all cross combinations, with the highest average frequency of diploid cells (28%) in T. carthlicum × L. arenarius crosses. A few selfed seeds have been obtained from a T. aestivum × L. arenarius hybrid. All the hybrids were treated twice with colchicine, but the treatment appeared to have little or no effect on the frequency of chromosome doubling in the hybrids deriving from T. aestivum. The frequency of diploid cells, however, increased significantly (e.g. to 80%) in the hybrids deriving from the T. carthlicum parent. Genomic in situ hybridization confirmed the hybridity of the plants and showed that the hybrids were amphiploids containing genomes of both wheat and lymegrass. In situ hybridization using ribosomal DNA probe differentiated chromosomes of L. mollis, L. arenarius from those of wheat. The hybrids are being backcrossed with lymegrass pollen, aiming to domesticate the wild, perennial species. This revised version was published online in July 2006 with corrections to the Cover Date.     

Transverse Seismic Design and Analysis of an H Type Bridge Tower Cable Stayed Bridge

According to our current bridge seismic design codes, the bridge tower is explicitly required to remain almost elastic even under the excitation of occasionally happened earthquake. To achieve this seismic performance objective, usually the steel ratios of tower base and strut are required to satisfy the static loading demand and increase by a large margin as well in most engineering practices which leads to engineering inefficiency as well as a rising seismic demand for the substructure. Therefore, the structural design parameters including the location, the stiffness and the constrain condition of the strut with respect to the tower column of H shape tower were studied to explore their effect on the transverse seismic responses of cable-stayed bridge tower, Moreover, the effect of yield intensity of the strut on the seismic responses of the tower column is also studied. The results show that the location and the stiffness of the strut have a slight effect on the seismic responses while the transverse seismic demands of the bridge tower decrease drastically when the constrain condition between the cross beam and the tower column changes.     

Development of a New Cytoplasmic Male-Sterility System in Brassica juncea through Wide Hybridization

A new cytoplasmic male-sterility system was developed in an oilseed Brassica, viz. B. juncea var. ‘Pusa Bold’ with the cytoplasmic background of a wild species, Diplotaxis siifolia, obtained through wide hybridization. The synthetic alloploid (D. siifolia×B. juncea: 2n = 56, D³D³AABB) was repeatedly backcrossed to B. juncea to achieve cytoplasmic substitution. The CMS plants resembled the cultivar in growth and morphology. The flowers had narrow sepals and petals and short, shrivelled anthers which failed to dehisce. The meiotic process appeared to be normal. The microspores degenerated at an early stage after tetrad formation. Female fertility in the CMS plants was as good as in the cultivar. Female transmission of sterility confirmed it to be cytoplasmically encoded.     

基于宽范围动态植被指数的棉花冠层覆盖度监测

 旨在利用宽范围动态植被指数对棉花冠层覆盖度进行监测,解决传统的利用归一化差值植被指数对冠层覆盖度较高时监测不准确(饱和)的问题。采用高光谱仪获取棉花不同时期不同覆盖度的冠层光谱反射率,通过对构成归一化差值植被指数的近红外波段反射率引入系数α来提高修正后的植被指数随棉花覆盖度变化的动态范围。当利用权重系数0.1≤α≤0.2对近红外波段反射率调整之后,新形成的宽范围动态植被指数用于监测不同覆盖度棉花时未出现“饱和”现象。利用宽范围动态植被指数建立的棉花覆盖度监测模型的决定系数r2＞0.948,对棉花冠层覆盖度进行监测,可以解决传统的归一化差值植被指数对冠层覆盖度较高时监测不准确(饱和)的问题,提高了植被指数对棉花冠层覆盖度监测的精度。     

剑麻叶片纤维细胞形态结构差异分析

观察分析剑麻叶片纤维细胞形态结构特征,及明确取样部位,为深入研究剑麻纤维细胞发育机制及形态提供基础性和实验性的参考。根据剑麻叶片及植株植物学特征确定取样部位,利用透射电镜（TEM）观察2个生长时期成熟叶片的不同区域和3个成熟度叶近轴端纤维细胞形态结构的差异。由电镜图片可知,剑麻不同生长时期叶片的中部和近轴端纤维细胞紧密相连、大小不一,但叶片中部区域多为不含原生质体的细胞壁结构,而近轴端细胞中存在含有细胞器的原生质体。进一步观察了3个成熟度叶片近轴端的纤维细胞形态,发现叶片纤维细胞中的各种细胞器被液泡挤压到细胞边缘,叶绿体为最突出的细胞器。幼年叶和成熟叶中的叶绿体多呈梭形,外膜完整,可见较清晰的片层结构和垛叠区,稚嫩叶的细胞中叶绿体出现皱缩及片层结构排列较紊乱,线粒体肿胀,胞浆内出现空泡,存在细胞核中异染色质增多和质壁分离的现象。综合分析图像信息推测,剑麻叶片纤维细胞生长发育活跃部位位于叶片近轴端,是观察剑麻纤维细胞结构的理想区域。     

Two-level Safety Evaluation and Structural Optimization of Steel Truss Bridge

A robust method for determining the component safety factor and structural safety factor of steel truss bridge is developed based on elastic modulus reduction method (EMRM). A procedure of two-level safety analysis and structural optimization is presented by means of the linear FEA iteration and the generalized yield criterion to take multiple internal forces into consideration. The strategy of elastic modulus adjustment is derived according to the principle of conversation of energy. The element bearing ratio (EBR) in every step can be obtained, and the first and last EBRs are employed to determine component safety factor and the structural safety factor for two-level structural safety evaluation of steel truss bridge. Those components with higher or lower EBR than the referenced EBR can be identified. By taking the quantitative relationship of the two level safety factors, a structural optimization scheme with better distribution of the EBR and saving material consumption can be achieved by adjusting the sectional strength of components with higher and lower EBR. Numerical examples show that the proposed method is promising with satisfying accuracy. The analysis of structural safety and optimization can be implemented by using the linear iteration while complicated nonlinear analysis in classical scheme is avoided.     

PD Online Measurement of Transformers with Wide Frequency Band System and the Noise Eliminating Method by Cascaded IIR Lattice Notch Digital Filter

The frequency band of conventional partial discharge (PD) measurement systems is selected just within several ten kilohertz. With the development of computer and digital signal processing techniques, wide frequency band (WFB) measurement systems have been used to detect PD in electrical equipment for its higher sensitivity. Nevertheless, the WFB measurement systems are easy suffered from the interference of strong field electromagnetism noises. A set of PD online monitoring system with frequency band from 50 kHz to 1 megahertz used for transformer is developed, in which pre-processing device and cascaded 2nd order IIR lattice notch digital filter are mainly used to suppress periodic narrow-band interference. With analysis of field monitored signal at a 220 kV substation, it is shown that the monitoring system not only can detect and extract the discharge pulse signal effectively, but also has the powerful capability of suppressing interference.     

One-Dimensional Nonlinear Consolidation Analysis of Clay Considering Structural Stress

One-dimensional nonlinear consolidation equations have been established taking into account the effect of structure stress ratio of natural clay and stepped time-dependent construction loading. Crank-Nicolson formula is adopted to solve these equations using the finite difference method. Numerical results are compared to those of linear and nonlinear consolidation taking no account of structure stress. Finally, effects of nonlinear parameter η/c on consolidation are analyzed, which indicates that consolidation rate increases with the decrease of η/c. Numerical results of considering structure stress or not are similar initially. With the development of consolidation, the nonlinear results of not considering the structure stress overestimate the effect of nonlinearity.     

茶树菇B交配型位点结构分析

为了探明茶树菇有性生殖内在分子机制,包括交配极性转换产生的同核体出菇问题.以茶树菇YSG同核体子代为实验菌株,依据基因组注释信息,利用嵌套引物验证B交配位点,设计引物扩增同核体群体,获得的扩增谱与菌株交配型进行比对.结果表明:(1)同核体培养后出现3种类型,菌丝型、无盖型和菌柄型,后两种为畸形子实体,不进行有性生殖;(...     

Structural Analysis of the Bolting Truss-column of Substation

Compared with the traditional welding truss-column in shape of A,the members of the bolting top-joint are much smaller than the common welding joint.Furthermore,the members are more convenience on fabrication,transportation and installation.It should be noted that the zinc process is much easier and cheaper.In this paper,by using the finite element method,the effect of many factors to the global stiffness and the intensity of the bolting truss-column are analyzed;the factors include the column height,the root width to column height ratio,the tube thickness,etc.The results obtained are favorable references for design and optimization of the bolting truss-column of substation.     

矮秆小麦亲本材料茎叶特性遗传分析

以5个矮秆小麦材料为母本,6个高产小麦为父本,采用不完全双列杂交设计,对小麦9个茎叶性状和6个穗部性状进行遗传分析。结果表明:9个茎叶性状的表现都是由加性和非加性基因共同决定的。各性状中遗传力均较高,除叶宽和结实小穗两性状外,其余性状的G.C.V均较大,表明对其选择和改良的潜力较大。大多数亲本的自身表现与一般配合力密切相关,绵阳01821、郑矮4号、绵阳04854具有很强的致矮力,是很好的致矮亲本。本文还探讨了各茎叶性状与穗部性状一般配合力的相关关系,指出小麦高产育种应注意协调好提高结实小穗、穗长、每穗粒数与提高穗下节长及穗颈节长间的关系。     

An Analysis on Specialization and Synthesis Development of ChongQing''s Industrial Structure

Through an analysis on specialization and synthesis development of Chongqing's three-D industrial structure and 13 major sectors, dominant specialization sectors and their status and functions, the relationships among dominant specialization sectors and non - specialization ones are given in this paper. This would be helpful for Chongqing to establish rational industrial policies, to upgrade its industrial structure level.     

Discussion on Second-order Analysis of Variable-Section Beam-Column

In this paper, based on the discussion of orthogonal decomposition method for the buckling mode of unsymmetrical structure, taking the variable-section beam-column as an example, a simple and direct method of the second order analysis is presented. In the new method, the conception of enlargement coefficient brought forward by Timoshenko is developed. To begin with the curvature of the variable-section beam-column, the linear equations are set up. With their solution, a group of orthogonal buckling mode can be obtained. The primary deflection can be decomposed to a group of homomorphic deflection similar to buckling mode. Then, the group of deflection is multiplied by corresponding enlargement coefficient and plus the result, finally, the second-order total deflection can be obtained.     

Analysis and Discussion on Klinglnberg'' s Cyclo-Palloid Bevel Gear

Because of their machining characteristics,Klinglnberg' s sprial bevel gears have the advantage over Gleason' s in many ways,so that they are more and more widely used. This paper analyzes the meshing and machining properties of the gears and deduces the equations,normal curveture and contact ratio of tooth surface. It also lays a solid foundation for spreading and importing the Klinglnberg' s machine,and developing klinglnberg' s gears.     

小麦脂质转运蛋白cDNA结构及相应肽链构造特征的分析

根据测序获得的1条261 bp cDNA片段,通过电子延伸、设计引物,从小麦Mardler/7*百农3217(Pm2)的cDNA中扩增获得1条651 bp的cDNA片段,通过同源比对发现其包含小麦LTP1 完整的编码序列.该片段包含基因的5'非翻译区42 bp,3'非翻译区261 bp,开放阅读框348 bp,编码115个氨基酸.预计蛋白的分子量为11.2 kD,等电点为9.46.此基因有8个位置保守的半胱氨酸(C)残基及25个氨基酸的信号肽,为典型的植物脂质转运蛋白基因.其基因序列数据库(GenBank)登录号为AY796184(基因)和AAV65513(蛋白).通过疏/亲水性分析,发现肽链分子具有较大范围的疏水面.