绥化市北林区气候变化与对策

根据北林区1953～2006年历年地面气象观测数据,采用一元回归方法,定量分析了绥化市北林区的气候变化,结果表明,研究期内该区气温升高,和热量相关的其他要素均有较明显的与增暖相对应的变化;降水年总量变化不大但各月略有不同变化,暴雨日数明显增加;日照时数有所减少;空气相对湿度稍有降低。并针对这些变化,提出了相应的应对措施。     

塔里木河下游垦区耕地面积变化及驱动力的多层次分析

通过引入土地利用/覆盖变化驱动力研究中常用的逐步回归方法和人文社会科学中最近兴起的多层次分析方法,研究了塔里木河下游垦区农二师五个团场耕地面积的影响因素,得到了团场层各变量和区域层变量对各团场耕地面积的影响程度,影响因素主要为,团场层:引水量、粮食产量、粮食种植面积、劳动力均种植业总产值;区域层:年蒸发总量、日照时数和最高、最低温。     

Induced expression of sucrose synthase and alcohol dehydrogenase I genes in phytoplasma-infected grapevine plants grown in the field

Interaction between phytoplasma and grapevine at the physiological level is still poorly understood, as are plant defence mechanisms against the pathogen. This study investigates the level of gene expression of three selected genes in a large number of grapevine plants belonging to six disease/cultivar groups (healthy Chardonnay, Bois noir-infected Chardonnay, Flavescence dorée-infected Barbera and Prosecco, and recovered Barbera and Prosecco). All plants were grown in vineyards in uncontrolled conditions in order to represent the physiology of disease as accurately as possible. Sucrose synthase was significantly upregulated in infected plants of all cultivars with the lowest P -values in cvs Chardonnay and Prosecco ( P  < 0·001) and median fold-change around 2. This clearly indicates that carbohydrate metabolism changed in infected compared to healthy or recovered plants. Alcohol dehydrogenase I was significantly upregulated in infected relative to healthy Chardonnay plants ( P  < 0·05) indicating that alcoholic fermentation, a sign of hypoxic conditions, was induced in infected plants. Heat shock protein 70 was upregulated in infected compared to recovered plants only in cv. Prosecco. Linear discriminant analysis showed that classification of samples into disease status groups based on gene expression was highly accurate (82%), indicating that the response of field-grown plants to phytoplasma infection at the level of expression of selected genes was so intensive and uniform that it was possible to detect it in grapevine plants regardless of natural variables.     

p21WAF1/CIP1蛋白在小鼠卵泡与黄体中的表达

【目的】研究p21WAF1/CIP1蛋白在成年小鼠卵泡发育与黄体形成及退化过程中表达的变化规律。【方法】取20只成年雌性小鼠的卵巢,制作石蜡切片,经免疫组织化学SP法染色后,观察p21WAF1/CIP1蛋白在原始卵泡、初级卵泡、次级卵泡、三级卵泡、成熟卵泡、闭锁卵泡、早期黄体、中期黄体以及晚期黄体中的定位及表达。【结果】卵泡发育和黄体形成及退化过程中均有p21WAF1/CIP1蛋白的表达;p21WAF1/CIP1蛋白在此过程中呈先升高后降低的趋势,峰值出现在三级卵泡时期。【结论】p21WAF1/CIP1蛋白在卵母细胞中发挥一定作用,可能参与优势卵泡的选择,并对卵泡发育及黄体形成和退化有影响。     

Effects of Pb Pollution on Seed Vigor of Three Rice Cultivars

An experiment was conducted to study the effects of different Pb concentrations on rice seed germination and seedling growth in three cultivars （Jiayu 293, Jiayu 948 and Xieyou 963）. The method of qualitative traits combining with quantitative traits by orthogonal polynomials was applied to analyze rice seed vigor by regression model. The seeds from different rice cultivars had different sensitivity to Pb poison. In the Pb concentration of 100-700 mg/L, Pb significantly decreased root length and shoot height, and the degree of the restraint would aggravate with the increasing of Pb concentration. However, Pb did not reduce root dry weight and shoot dry weight, which indicated that different physiological characteristics had different sensitive reactions to Pb. The predicting equations of regression were developed, which could be used to predict the effects of different Pb concentrations on rice seed vigor.     

密度和施氮量对油菜产量构成因素影响的旋转回归分析

运用二因素五水平回归正交旋转组合设计的实验方法,进行氮肥与密度对油菜产量构成因素影响的研究。结果表明,在试验范围内,施氮量和密度对油菜单株有效角果数均有显著的影响,但密度的变化对单株有效角果数的影响大于氮肥施用量对单株有效角果数的影响。当密度为93.72~105千株/hm2,氮肥施用量为225~227.02㎏/hm2时,油菜的单株有效角果数可望达到最高;氮肥和密度对于油菜每角粒数和千粒重的影响不显著。     

Relating soil electrical conductivity to remote sensing and other soil properties for assessing soil salinity in northeast Thailand

Mapping and monitoring of soil salinity is required to establish its areal extent and also to keep track of changes in salinity in order to formulate appropriate and timely management strategies for reclamation and rehabilitation of such soils. Remote sensing data have been increasingly used in soil‐salinity studies as they are not only quicker but are also useful for making realistic predictions. A study was conducted in northeast Thailand to understand the relationship of spectral reflectance and physico‐chemical soil properties to electrical conductivity (EC) by using remote sensing data (Landsat® ETM+) and laboratory analysis of soil sample data. Multiple regression analysis was used to examine the relationships between EC and spectral/soil properties and to generate several models. In the case of spectral properties, mid‐infrared band (Landsat® band 7) and near‐infrared (band 4) were found to be most correlated with the observed EC values of the surface layer of the soil. For the soil properties, chloride (Cl), sodium (Na), phosphorus (P), and sodium adsorption ratio (SAR) were found to be most correlated with observed EC values. Similarly, for the subsurface layer, Cl and P were found to be significant predictors of observed EC values. Copyright © 2006 John Wiley & Sons, Ltd.     

利用LINEST函数进行多元线性回归分析

本文介绍了最小二乘法基本理论,并结合肥料试验数据处理对LINEST函数的应用进行了详细讲解。     

柱花草高产栽培综合农艺措施的研究

试验采用５因素二交正交旋转组合回归设计,对柱花草高产栽培的综合农艺措施进行研究,并建立了千物质产量与种植密度,收割次数、施过磷酸钙量、施复合肥量、喷施钼酸铵浓度先进５项农艺措施之间的数学模型,通过模型解析和寻优,得出在试验条件下,５项农艺措施对热研２号柱花草产量影响的程度依次为：收缩次数〉种植密度〉复合肥量〉施过磷酸钙量〉喷施钼酸铵浓度,并得出高产栽培组合方案。     

回归分析方法在库尔勒市农用地定级中的应用

使用库尔勒市3 089个农用地定级单元,在SPSS软件的基础上,用回归分析法选择农用地定级因素,确定各因素权重,并计算各定级单元总分,然后对总分作频率统计,绘制频率直方图,按农用地优劣的实际情况,选择频率曲线分布突变处为级间分界,划分农用地级别.