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M. Hren M. Ravnikar J. Brzin P. Ermacora L. Carraro P. A. Bianco P. Casati M. Borgo E. Angelini A. Rotter K. Gruden 《Plant pathology》2009,58(1):170-180
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. 相似文献
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【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。 相似文献
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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. 相似文献
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密度和施氮量对油菜产量构成因素影响的旋转回归分析 总被引:8,自引:0,他引:8
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。 相似文献
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R. P. Shrestha 《Land Degradation \u0026amp; Development》2006,17(6):677-689
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. 相似文献
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