水稻向地性突变体的鉴定与遗传和定位分析

从水稻籼稻品种E优428的诱变M1代群体中获得向地性突变体la(t),该突变体在苗期倒伏生长,成熟期呈匍匐型生长,其它性状未发现异常。初步的生理研究表明该突变体不受外源激素(2,4-D,赤酶素)和光照的影响,并失去了感受重力的能力。遗传分析表明,该突变属单基因隐性突变,将该基因暂定名为la(t)。利用该突变体与籼稻品种D62B杂交,构建了F2代分离群体,用微卫星标记分析,将该基因定位于水稻第11染色体上的微卫星标记Lu2和Lu18之间,与目的基因分别相距1.0和1.7cM。通过电子杂交的方法将该基因所在区域的遗传图谱整合到国际水稻基因组计划的水稻第11染色体物理图谱中,其la(t)基因两端毗连的Lu2和Lu18SSR标记之间的物理距离约为140～200kb。为用图位克隆法分离此目的基因和研究水稻向地性生长的分子机理奠定基础。     

六角亭的透视图画法分析

以六角亭为例,通过对六角亭各部分透视的分析,提出了亭子透视图的画图步骤。     

激光致等离子体及其对激光加工的影响

论述了激光致等离子体机理和激光致等离子体在光束一工件能量耦合过程中的作用。对等离子体振荡与逆韧致副射吸收作了物理讨论，导出了等离子振荡频率和吸收系数公式。     

TM卫片目视土壤解译的制图技术

应用“地形、地貌、岩性、母质综合影像制图技术”,目视解译TM放大图像,以土属为单位,其解译准确率在94％以上,可解译图斑达98.1％。解译成图精度合乎全国第二次土壤普查质量要求,并具有经济、快速的特点。对及时更新省、地土壤图和进行土壤资源调查和定位监测,将开拓一条多快好省的新途径。     

大豆苗期耐旱种质鉴定和相关根系性状QTL定位

从301份大豆品种中按根系类型选取黄淮海和长江中下游地区代表性材料59份,在苗期干旱胁迫和非胁迫条件下对地上部和地下部性状进行2年重复鉴定,发现材料间性状隶属函数值具有丰富遗传变异,以株高、叶龄、根干重和茎叶干重隶属函数的算术平均数为抗旱综合指标从中筛选出汉中八月黄、晋豆14、科丰1号、圆黑豆等强耐旱型(1级)和临河大粉青、宁海晚黄豆等干旱敏感型(5级)材料。比根干重、比根总长、比根体积与耐旱隶属函数平均值均呈极显著正相关,可作为耐旱性的根系性状指标。利用“科丰1号×南农1138-2”(1级×4级)衍生的R IL群体为材料,对耐旱相关根系性状进行QTL定位。检测到5、3、5个QTL s分别控制比根重、比根总长、比根体积,位于N 6-C 2、N 8-D 1b W、N 11-E、N 18-K连锁群上。3个性状各有1个贡献率大的QTL(Dw 1、R l1、R v1),而且均位在N 6-C 2的STA S8_3T-STA S8_6T相同距离的区段上,其他QTL s效应均较小。     

一类次对称矩阵反问题的最小二乘解

讨论了一类次对称矩阵反问题的最小二乘解，得到了解的具体表达式；并就这类矩阵的左右逆特征对问题进行了讨论，得到了有解的充分条件及解的通式。     

学分制改革中的《测量学》实践研究——以河南农业大学为例

从河南农业大学学分制改革现状出发,分析了当前《测量学》教学中存在的问题,并阐述了通过改革《测量学》课程计划,适应学分制发展的对策。     

An Evaluation of the Response of Yield Monitors and Combines to Varying Yields

Comparisons were made between yield measurements with an impact based yield sensor and an electronic scale in adjacent harvest strips and on the same grain stream within a combine. Yield measurements in adjacent strip comparisons were more prone to errors as the segment lengths decreased. Grain yield difference between the yield sensor and electronic scale ranged from 5 to 14%, 4 to 13%, 3 to 12%, and 2 to 11% for 15, 30, 60, and 300 m long segments. The yield differences between neighboring segments might have been caused by yield variability to a degree; however, a consistent decrease in yield differences with increasing segment lengths implied that better accuracies could be obtained in longer management areas. The combine responses to grain yield changes and the effect of varying ground speed on accuracy were also evaluated by creating artificial yield patterns in harvest strips. Grain diffusion within the combine was more obvious when abrupt yield changes were introduced at known locations. Grain mixing and redistribution inside the combine may dictate the selection of segment sizes in the site-specific decision making process. Constant ground speed provided more stable grain flow values than varying ground speed. The average error in yield estimate was 3.4% and 5.2% at constant ground speed and varying speed, respectively. Careful calibration and constant combine speed were important to achieve better accuracy with the grain yield monitor.     

Mapping of Microsatellite SW943 to Porcine Chromosome 12p11-(2/3p13) Using Primed in situ Synthesis and Somatic Cell Hybrid Panel

The porcine microsatellite SW943 was regionally localized on 12p11-(2/3p13) by the two methods: the Primed in situ (PRINS) labelling on the pachytene bivalents of pigs using the Dig-11-dUTP as the report molecule and pig × rodent Somatic Cell Hybrid PaneI(SCHP) which contains 27 cell lines through PCR amplification. Advantages and disadvantages of the two methods for physical mapping of microsatellites were also discussed.     

Molecular Mapping of Two Novel Stripe Rust Resistant Genes YrTp1 and YrTp2 in A-3 Derived from Triticum aestivum × Thinopyrum ponticum

Loss of variety resistance to stripe rust (Puccinia striiformis Westend f. sp. tritici) is an important factor causing massive periodical epidemic of rust in wheat production. Creation and development of new races of rust pathogen have led to serious crisis of resistance loss in widely planted varieties. This has quickened the search for new resistance resources.Molecular marker could facilitate the identification of the location of novel genes. A line A-3 with high resistance(immune) to currently epidemic yellow rust races (CY29, 31, 32) was screened out in offspring of Triticum aestivum ×Thinopyrum ponticum. Segregation in F2 and BC1 populations indicated that the resistance was controlled by two independent genes: one dominant and one recessive. SSR markers were employed to map the two resistant genes in the F2 and BC1 populations. A marker WMC477-167bp located on 2BS was linked to the dominant gene with genetic distance of 0.4 cM. Another marker WMC364-208bp located on 7BS was linked to the recessive-resistant gene with genetic distance of 5.8 cM. The two genes identified in this paper might be two novel stripe rust resistant genes, which were temporarily designated as YrTpl and YrTp2, respectively. The tightly linking markers facilitate transfer of the two resistant genes into the new varieties to control epidemic of yellow rust.