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1.
玉米叶片硝酸还原酶活性测定条件的优化   总被引:2,自引:0,他引:2  
以玉米品种农大108幼苗为材料,研究了温度、pH值、叶位及一天中的不同时段对硝酸还原酶(NR)活性的影响,同时对光照及三氯乙酸(TCA)对NR的影响效应进行了评价。结果表明,玉米硝酸还原酶在24℃,pH 7.5下的活力最高;不同叶位,刚刚展开的叶片(心2叶)活性极显著高于其它叶位;NR在一天中的不同时段活性不同,以15:00的活性最高。不同测定条件下,与照光处理相比,黑暗条件下的酶活性显著提高。此外,加入变性剂三氯乙酸使玉米叶片内的NR活性明显减低。  相似文献   

2.
硝酸还原酶(NR)是植物氮素代谢中的关键酶,可作为植物育种和营养诊断的生化指标,近五年来我国在稻、麦、玉米等作物上,亦已揭示出NR活力与作物耐肥性呈负相关这一规律,因此测定NR活力的大小,能够反应作物耐肥性能的弱或强。硝酸还原酶的测定方法有体外法(in Vitro)及体内法两种,体外法测定的数据比较精  相似文献   

3.
优质(低芥酸、低硫甙)油莱与普通油莱的营养生理特征有明显不同,其植株的可溶性总糖及含氮量在苗前期与成熟期差异很小,到越冬期、苔期和花期则相差很大,出现“梭形过程”。优质油莱在这一过程中表现“糖高氮低”,其硝态氮含量、硝酸还原酶(NR)活力及光合作用速率等生理特征均表现较弱,对氮肥反映较敏感,每生产100公斤菜籽的需氮量相对较少。  相似文献   

4.
晴好天气下,测定2种蔷薇科植物珍珠梅(Sorbaria sorbifolia A.Br)和榆叶梅(Prunus triloba Lindl.)茎直径、木质部直径、韧皮部直径、木质部含水量、叶水分亏缺和蒸腾速率日变化.结果表明,珍珠梅和榆叶梅茎直径呈现白天收缩,傍晚、夜间恢复或者膨胀的变化过程.珍珠梅和榆叶梅木质部直径变化趋势与茎直径变化趋势一致,而韧皮部直径无明显变化;相关分析表明木质部直径变化与茎直径变化呈现极显著正相关,说明木质部直径的变化是引起茎直径变化的主要原因.珍珠梅和榆叶梅木质部含水量与其木质部直径呈现极显著正相关;茎直径与叶水分亏缺呈现极显著负相关性,与水分代谢有密切关系.说明珍珠梅和榆叶梅的茎直径变化是由体内水分平衡决定的.  相似文献   

5.
为了明确缺氮条件下甜菜NR的活性,用活体测定法检测了经缺氮胁迫不同时间后甜菜叶中NR活性.结果表明,随着缺氮处理时间的延长,甜菜叶中的NR活性逐渐降低,在缺氯处理1h后,其活性下降较快.用50mmol/1.KNO3溶液处理的甜菜幼苗总RNA,通过RT—PCR分离得到了硝酸还原酶基因片段,长度为471bp,Blast分析表明,其与Genbank中硝酸还原酶基因部分序列具有高度同源性.  相似文献   

6.
内蒙古典型草原常见种营养元素生殖分配动态规律研究   总被引:1,自引:0,他引:1  
测定了锡林郭勒草原中12种常见植物种群在不同的物侯期(营养、花蕾、结实)不同器官(茎、叶、花、果)中6种营养元素(C、N、P、K、Ca、Mg)的含量,以其探索随物侯期的变化,营养元素在生殖分配上的动态规律。结果如下:①茎中的营养元素不随物侯期的变化而变化;营养元素含量在营养期叶中既与不同物侯期的叶有明显区别,又与同一物侯期的不同器官(营养期茎)有明显差异。②不同植物种群的6种营养元素生殖分配只在营养物侯内表现一致,叶中分配比例明显大于茎中的,在茎中占20%-35%,叶中占65%-80%。  相似文献   

7.
作物根系吸收硝态氮后,运往叫片先被还原成氨态氮,然后合成为有机氮。在硝态氮还原过程中,硝酸还原酶(NR)起着调控作用。有关作物耐肥性的研究亦已阐明,作物对氮素的反应特性与NR活性存在着负相关,不同品种间NR活力的差异,主要是由于体内酶的诱导合成水平不同而造成。由于NR是一种诱导酶,在植物体内极不稳定,诸如光强、温度、pH、CO_2、O_2分压、水势、氮的供应水平等等因素,都会导致NR活性的变化和波  相似文献   

8.
在不同耐肥性的6个小麦品种幼苗中,硝酸还原酶(NR)活力差异显著,耐肥性弱的品种NR活力高,活力是负相关关系。过氧化物酶活力,耐肥性强的高于耐肥性弱的。根据聚丙烯酰胺凝胶电泳分离出的过氧化物酶的同工酶谱,耐肥性强的品种均有8条酶带,且着色深,耐肥性弱的品种则有7条,着色较浅。此外通过根系活力测定,耐肥性强的低于耐肥性弱的品种,而叶绿素含量则高于耐肥性弱的品种。  相似文献   

9.
三种蛋白质含量不同的水稻品种,其幼苗的硝酸还原酶的活力不同,叶绿素和硝态氮的含量也不同,凡叶绿素和硝态氮含量亭的其硝酸还原酶的活力也高,凡叶绿素和硝态氮含量低的其硝酸还原酶的活力也低。华03的谷粒蛋白质含量高。其幼苗根系对铵态氮的吸收能力也强。上述结果说明,蛋白质含量不同的水稻品种,其生理生化差异在幼苗期已表现对氮的吸收和利用不同。  相似文献   

10.
宁夏区内5种牧草可溶性糖和淀粉含量的研究   总被引:3,自引:0,他引:3  
采用蒽酮比色法对豆科5种牧草营养期组织中可溶性糖和淀粉的含量进行了测定及分析.结果表明,在营 养期,同一牧草的不同器官内可溶性糖和淀粉的含量有一定的差异,即叶部>茎部>根部;不同牧草间可溶性糖和 淀粉的含量也存在差异,即紫花苜蓿>胡枝子>沙打旺>柠条>羊柴.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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