延边黄牛MYH3和MYH8基因多态性及其与生长性状的关联分析

本研究旨在探索延边黄牛肌球蛋白重链3（MYH3）和肌球蛋白重链8（MYH8）基因多态性及其与生长性状的关联性,应用DNA直接测序法和高分辨率熔解曲线分型技术对120头24月龄延边黄牛MYH3、MYH8基因的遗传变异进行分析,并结合延边黄牛生长性状数据进行了关联分析。结果显示,在MYH3基因的29602748位点检测到一处T>G突变,包含2个等位基因：T和G,存在3种基因型：TG、TT和GG;在MYH8基因的29406042位点检测到一处C>T突变,包含2个等位基因：C和T,存在3种基因型：CT、CC和TT。关联分析显示,MYH3基因29602748位点T>G突变显著影响24月龄延边黄牛十字部高和腰角宽,表现为GG基因型十字部高显著高于TT基因型（P<0.05）,腰角宽显著高于TT和TG基因型（P<0.05）。MYH8基因29406042位点C>T突变显著影响24月龄延边黄牛体重和胸围,表现为CT和TT基因型体重显著高于CC基因型（P<0.05）;TT基因型胸围显著高于CC基因型（P<0.05）。本研究结果表明,MYH3、MYH8基因多态性与延边黄牛的部分生长性状相关,可作为现代肉牛育种中分子标记辅助选择的候选基因。     

兰州引黄灌区玉米田杂草群落及生态位研究

对兰州引黄灌区玉米田杂草进行了研究,初步了解了其杂草种类和杂草种群的消长动态。主要杂草有打碗花、田旋花、藜、刺儿菜、荠菜、稗草、马齿苋、反枝苋、狗尾草。主要杂草的干重为藜、反枝苋、稗草分别列第1、第2和第3位。生态位的研究结果表明,藜的时间、水平、垂直生态位宽度值最高,分别为0.952 6,0.971 8,0.937 9,其危害最大;其次为反枝苋和稗草。藜、反枝苋和稗草为优势种群,与玉米存在时间、水平、垂直空间的竞争激烈,并且这3种杂草的生态位重叠值也最大,因此在使用一种除草剂时,可能会导致另两种杂草的发生与蔓延。马齿苋尽管数量最多,但其在垂直方位的生态位宽度值最小,对玉米影响小,处于劣势。除草处理各经济性状指标值均较不除草对照高,其折合产量为10 111.11 kg/hm2,较不除草处理增产36.19%。     

Characterization,phylogenetic analyses and pathogenicity of Bipolaris setariae associated with brown stripe disease on sugarcane in Yunnan,China

Brown stripe disease is a severe foliar fungal disease of sugarcane worldwide and is widespread in all sugarcane planting areas in China. Brown stripe is a major disease that seriously affects the output and quality of the sugarcane industry in Yunnan Province, China's second-largest sugar base, while the pathogen of this disease remains not yet fully understood. To address this, we isolated and identified the fungi associated with 68 leaf samples showing typical symptoms of brown stripe from 22 sugarcane varieties in different areas of Yunnan Province. A total of 113 isolates were obtained, which were morphologically similar. Of these, 64 representative isolates were sequenced for the internal transcribed spacer region (ITS), GAPDH and EF-1α loci. All representative isolates grouped with the type strain of Bipolaris setariae in the phylogenetic trees inferred with individual and concatenated sequences of ITS, GAPDH and EF1-α. Pathogenicity test results showed that B. setariae strains were able to induce typical symptoms of brown stripe. The results obtained in this study clarify that only B. setariae is associated with sugarcane brown stripe in Yunnan, China. It is recorded here for the first time as a pathogen causing sugarcane brown stripe in Yunnan, and it is able to infect many major cultivars and new varieties, posing a new threat to the sugar industry in Yunnan Province. In addition, these results provide the scientific basis for the future breeding of disease-resistant varieties and effective prevention and control of sugarcane brown stripe disease.     

白菜型油菜DFR基因的克隆与序列分析

By using RACE (rapid amplification ofcDNA ends) based homologous cloning strategy, we have successfully isolated the genomic and full-length cDNA sequences of a gene encoding typical DFR (dihydroflavonol-4-reductase) from black-seeded Brassica campestris L. var. oleifera DC.. The gene, designated BcDFR here, is 1 722bp in length and harbors 5 introns with typical splice sites of plant DFR genes. BcDFR cDNA is 1311bp in length with a 1 158bp ORF as well as a 25bp 5‘ UTR and a 128bp 3‘ UTR. The encoded BcDFR protein is 385 aa with a calculated Mw of 42.85kD and a pI value of 5.55. The nucleotide and amino acid sequences of this gene share extensive homologies to plant DFR genes of wide origins especially high similarities to Cruciferous DFR genes. Sequence analyses such as phylogenetic analysis, conserved domain search and substrate specificity region detection all indicated that BcDFR gene is a quite potentially biofunctional gene. Its cloning enables us to further dissect the possible relatedness between DFR gene and Brassica seed coat color traits and to create transgenic novel yellow-seeded rapeseed germplasm through antisense- or RNAi-suppression of DFR gene expression in black-seeded elite cultivars.     

Application and Advancement of Reinforced Earth Technique

In this paper, the application of reinforced earth technique, principle and calculation method, new reinforced materials developed and produced are introduced. A few of key technical problems in reinforced earth application is discussed, such as reinforced earth behavior, calculation method, durability of reinforced material, amendment and complement of the current standards. Then, the reinforced earth technique development and advancement were introduced.     

Research on Design Methods for Reinforced Earth Retaining Wall with Cohesive Backfill

For the stability analysis of the reinforced earth retaining wall with cohesive backfill, this paper assumes that the state of failure surface is circular sliding surface and the bearing capacity is straight line relation with capacity and length of the reinforcement strip. These formulas agree with actual state of the reinforced earth retaining wall with cohesive backfill and result in saving reinforcement material in the design.     

几个外引水稻品种在河南沿黄地区的表现

通过对几个外引水稻品种在河南沿黄地区引种试验，表明杂交稻生长速度快，抽穗较晚，但分蘖力强、成穗率高、穗粒数多，产量的增产潜力较大。除金世纪外其他几个品种与豫粳6号相比基本持平，但产量也有不同程度的提高。但金世纪品质与豫粳6号相比有较大的提高，产量也提高。     

增加投入实现引黄灌溉良性发展

引黄灌溉经济效益显著,但是灌区管理单位的财务收益却入不敷出。根据经济效益分析与水费收交情况,作者认为应加强水费回收,多方面集资以及深化水费改革等,以利于灌溉事业的良性发展。     

基于水量平衡的宁夏引黄灌区广义生态耗水量计算

基于区域的水量平衡理论,对宁夏引黄灌区的广义生态耗水量进行计算,同时对灌区生态耗水量与灌区引黄水量的关系也进行了研究。研究结果表明:灌区各年的广义生态耗水总量差别并不大,没有表现出非常强烈的上升或下降趋势,耗水量的小范围变动与灌区引黄水量关系不明显。     

宁蒙引黄灌区田间节水潜力计算方法分析

以黄河干流宁蒙大型自流引黄灌区为研究对象,采用分项法以及两种计算顺序对宁蒙引黄灌区田间节水潜力进行了计算,分析了不同计算顺序对田间节水潜力计算结果的影响,并采用综合法对分项法计算结果进行了验证,表明计算方法可靠。