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1.
Hypersensitive response (HR) is one of the most efficient and common resistance mechanisms in plants. Cloning signaling genes are very important to elucidate the resistance mechanisms. A gene in tomato homologous to several resistance proteins in plant was involved in HR and named as RGL (Resistance Gene Like). RGL protein was used as a bait to screen interacting protein(s) from tomato cDNA library through the yeast two-hybrid system. Two interacting proteins were found, which were called as RGLIP-1 and RGLIP-2 (RGL Interacting Protein), respectively. RGLIP-1 is a protein of 291 amino acids with significant homology with thylakoid lumen protein. RGLIP-2 is a protein of 248 amino acids with significant homology with transducin protein. Virus-Induced Gene Silencing (VIGS) of the two genes results in a partial and complete suppression of Avr4-induced HR, which indicates that both genes are involved in hypersensitive response. __________ Translated from Acta Horticulturae Sinica, 2006, 33(1): 52–57 [译自: 园艺学报]  相似文献   
2.
近 5 0年来石油工业迅速发展 ,在农业生产上由于超量使用化肥、农药 ,环境污染日益严重。因此 ,可持续农业发展 ,引起社会上的普遍关注 ,不使用化学合成的肥料、农药 ,改用有机肥、堆肥进行蔬菜生产是行之有效的方法。科学研究证明植物可以直接吸收有机物 ,用有机方法生产蔬菜 ,对环境无污染 ,产品质量好 ,味道纯正 ,有益健康。目前无土栽培大多数是全部用化肥配制营养液进行作物生产 ,产品硝酸盐含量偏高 ,对人体健康不利 ,如改用有机肥和生物防治病虫 ,就可以生产绿色食品蔬菜 ,这是 2 1世纪农业发展的方向  相似文献   
3.
针对项目建设实施过程中存在的问题,文章从业主方面、监管单位方面以及施工单位方面分析了项目管理存在的误区和问题,最后提出解决项目管理问题的思路。  相似文献   
4.
正Introduction Ending poverty in all its forms everywhere is the first Sustainable Development Goal(SDG) of the United Nations(2021a). Progress towards this goal has varied but also been fruitful. Between 1990 and 2015, over a billion people were lifted out of extreme poverty(World Bank 2018). From 36% of the population under extreme poverty in 1990 to 10% in 2015(United Nations 2021b).  相似文献   
5.
中央级科学事业单位修缮购置专项是贯彻落实国家中长期科技发展规划,加快科技创新工作的重要举措,认真总结与分析专项管理经验对于加快农业科学事业单位发展,提升我国农业科技创新能力,发展现代农业等具有重要意义。文章阐述了修缮购置专项产生的背景、内涵与基本特征,并对修缮购置专项的模式进行了对比分析。最后提出树立正确理念,支持专项管理,创新工作方法,提高管理效率等4点建议。  相似文献   
6.
以1961−2018年长时间序列的格点化气象数据替代以往研究中站点数据,通过趋势分析和聚类分析等方法,研究中国区域内适合格点数据的霜冻辨识阈值、霜冻发生时间及霜冻强度的时空变化规律,以在气候变化背景下合理利用气候资源,降低霜冻灾害给农业生产造成的损失。结果表明:(1)日最低气温0℃相比日最低气温2℃作为阈值辨识初/终霜冻和无霜期的空间分布更加合理。(2)1961−2018年中国大部分地区初霜冻日期推后(1~3d·10a−1),终霜冻日期提前,无霜期增加(1~3d·10a−1)。(3)不同强度的霜冻年累计发生次数在中国北方有微弱增加态势,在南方呈现明显的减少趋势。其中,晚霜冻不同霜冻强度年发生频次高于早霜冻。(4)以霜冻日期和霜冻发生频数为标准进行中国霜冻灾害区划,全国可分为亚热带、暖温带、中温带、寒温带和青藏高原5个分区。其中,以青藏高原不同霜冻日期变化最为剧烈。整体上,中国区域的气候变暖对于霜冻灾害的发生在时间、空间和强度上有明显的减弱效果。  相似文献   
7.
8.
用水稻基因芯片筛选小麦耐旱相关基因   总被引:2,自引:0,他引:2  
为了解小麦在干旱逆境条件下的基因转录规律,采用PEG6000对耐旱小麦(Triticum aestivum)品种旱选10号进行拟旱处理,分别提取0、1、6和24h植株的总RNA,经反转录荧光标记制备cDNA探针,并将其与含有6万Oligo的水稻全基因组芯片进行杂交,扫描采集数据后并进行结果分析。在1、6和24h样品中分别检测到差异表达基因166、207和328个,随着处理时间的延长,差异表达基因数目增加。对差异基因进行功能分类,能量代谢途径相关基因在1、6和24h差异表达基因总数中所占比例分别为4.2%、8.2%和16.8%,其中大部分为光合作用相关基因,并且主要表现为上调,但Psbr和Rubisco编码基因的转录水平为下调,暗示它们在耐旱反应中发挥着一定作用。  相似文献   
9.
A pot experiment was conducted in a glass-house to investigate the correlation between specific fine root length (SFRL) and root colonization (RC) of maize inoculated with six arbuscular mycorrhizal fungi (AMF) in three soil types. The results showed that six AMF associated with maize presented different abilities in RC and effects on SFRL. In addition, there was a significant correlation between SFRL and RC of arbuscular mycorrhizal maize in Beijing soil (Cinnamon soil), but no significant correlation in Hubei soil (Brunisolic soil) and Guangdong soil (Red soil). It is concluded that mycorrhizal colonization decreased the SFRL of maize, and the correlation between SFRL and RC of mycorrhizal maize depended on soil type.  相似文献   
10.
    
The monitoring of crop production and irrigation at a regional scale can be based on the use of ecosystem process models and remote sensing data. The former simulate the time courses of the main biophysical variables which affect crop photosynthesis and water consumption at a fine time step (hourly or daily); the latter allows to provide the spatial distribution of these variables over a region of interest at a time span from 10 days to a month. In this context, this study investigates the feasibility of using the normalised difference vegetation index (NDVI) derived from remote sensing data to provide indirect estimates of: (1) the leaf area index (LAI), which is a key-variable of many crop process models; and (2) crop coefficients, which represent the ratio of actual (AET) to reference (ET0) evapotranspiration.A first analysis is performed based on a dataset collected at field in an irrigated area of the Haouz plain (region of Marrakesh, Central Morocco) during the 2002–2003 agricultural season. The seasonal courses of NDVI, LAI, AET and ET0 have been compared, then crop coefficients have been calculated using a method that allows roughly to separate soil evaporation from plant transpiration. This allows to compute the crop basal coefficient (Kcb) restricted to the plant transpiration process. Finally, three relationships have been established. The relationships between LAI and NDVI as well as between LAI and Kcb were found both exponential, with associated errors of 30% and 15%, respectively. Because the NDVI saturates at high LAI values (>4), the use of remotely-sensed data results in poor accuracy of LAI estimates for well-developed canopies. However, this inaccuracy was not found critical for transpiration estimates since AET appears limited to ET0 for well-developed canopies. As a consequence, the relationship between NDVI and Kcb was found linear and of good accuracy (15%).Based on these relationships, maps of LAI and transpiration requirements have been derived from two Landsat7-ETM+ images acquired at the beginning and the middle of the agricultural season. These maps show the space and time variability in crop development and water requirements over a 3 km × 3 km irrigated area that surrounds the fields of study. They may give an indication on how the water should be distributed over the area of interest in order to improve the efficiency of irrigation. The availability, in the near future, of Earth Observation Systems designed to provide both high spatial resolution (10 m) and frequent revisit (day) would make it feasible to set up such approaches for the operational monitoring of crop phenology and irrigation at a regional scale.  相似文献   
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