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1.
对脱毒裂萼草莓的叶绿素含量、生长温度、光强及叶绿素荧光参数变化进行了研究,结果表明:脱毒裂萼草莓叶绿素含量为2.885 mg/g.fw,较病叶提高了21.58%;在光强为0~2000μmolm-2s-1范围内,净光合速率(Pn)随光强的增加而增加,直到光饱和点,最大值为10.5μmol CO2m-2s-1;在温度为0~17℃时,Pn随温度增加而升高,17~40℃时,Pn随温度增加而下降,测出其最适生长温度为17℃左右;叶绿素荧光参数Fv/Fm变化较小.  相似文献   

2.
不同土壤条件对曼地亚红豆杉幼苗的影响   总被引:2,自引:0,他引:2  
对曼地亚红豆杉在不同土壤条件下的生长及代谢的研究表明:酸壤、碱壤条件下生长的曼地亚红豆杉光饱和点分别为:1 050μmol.m-2.s-1,887μmol.m-2.s-1;光补偿点分别为136μmol.m-2.s-1,117μmol.m-2.s-1.酸性土壤下的幼苗增大了叶绿素含量、净光合速率和可溶性糖含量,而光呼吸速率和可溶性蛋白质降低.酸壤下生长的幼苗叶绿素含量、表观量子效率、叶片厚度、叶面积及生物量较高.酸性土壤环境是曼地亚红豆杉较适宜的生长环境.  相似文献   

3.
罗勒是一种食药兼用的资源植物。通过对罗勒光合特性的研究,旨在为罗勒的栽培提供理论依据。实验结果表明:罗勒的光合日变化呈双峰型,第一峰出现在上午11:00左右,Pn约为7.87μmolCO2.m-2.s-1,第二峰值出现在15:00左右,Pn约为5.68μmolCO.2m-2.s-1,"午休"现象明显。在400μmol.mol-1CO2浓度下,罗勒的光饱和点为1 800μmol.m-2.s-1左右,光补偿点为75μmol.m-2.s-1左右,CO2饱和点在600μmolCO2.mol-1左右,而CO2补偿点约为60.7μmolCO2.mol-1。  相似文献   

4.
砂仁叶片光合作用光抑制及其防御   总被引:1,自引:0,他引:1  
用脉冲叶绿素荧光仪测定砂仁叶片叶绿素荧光参数的日变化及阻止卷叶对其影响后发现Fv/Fm、Fv'/Fm'、Fm、Fv、Fm/Fo、Fv/Fo随光强的增加而降低,中午达到最低值后随光强的减弱而升高,Fo则一直在降低,NPQ、qN及qE-fast和qE-slow随光强的增加而升高;阻止卷叶后荧光参数的日变化更明显,光合放氧量子效率也降低.结论光抑制条件下砂仁叶片通过热耗散,卷叶等保证光合机构不被破坏.  相似文献   

5.
为比较筛选虎耳草优良品种,运用LI-6400便携式光合仪对虎耳草叶片光合特性进行了测定,并且采用HPLC测定了虎耳草全株岩白菜素和没食子酸含量.结果表明:湖南中方仙人谷虎耳草叶片净光合速率最高,为6.85μmol·m-2·s-1,该居群虎耳草的岩白菜素含量也最高,为3.94 mg·g-1.相关性分析结果表明,岩白菜素含量与净光合速率显著正相关,与总叶绿素含量极显著正相关;没食子酸含量与光合参数的相关系数均未达显著水平.  相似文献   

6.
扦插繁殖是植物重要的营养繁殖方式之一,但很难快速确定其最佳的扦插条件.利用叶绿素荧光仪检测不同IAA浓度处理及不同温度条件下的日本荚蒾扦插苗的叶绿素荧光参数的变化进行研究.结果表明,日本荚蒾的非循环电子传递速率及非光化学淬灭系数随光照强度的增加而增加,最终保持稳定;光化学焠灭系数随着光照强度的增加而降低,最终趋于稳定;不同温度和IAA浓度处理,各项叶绿素荧光参数变化存在差异.结论:日本荚蒾最佳扦插条件为20℃、IAA激素浓度为0.1%;叶绿素荧光技术可作为快速确定植物最佳扦插条件技术.  相似文献   

7.
低温弱光对茄子幼苗膜脂过氧化和细胞膜保护酶系的影响   总被引:3,自引:0,他引:3  
研究了低温弱光对茄子幼苗叶片叶绿素(Chl.)、脯氨酸(Pro.)、丙二醛(MDA)含量以及过氧化物酶(POD)和过氧化氢酶(CAT)活性的影响.结果表明:经低温弱光(10℃/5℃,光照强度60和120μmol.m~.s-1)处理7d后Chl.含量显著降低,Pro.和MDA含量有不同程度的升高,POD和CAT活性则明显下降;且各指标以低温下较强的光(120μmol.m-2.s-1)处理的变化幅度大.恢复7d后,Chl.含量仍显著低于对照,MDA含量基本恢复到对照水平,Pro.含量也有大幅度的降低,POD和CAT活性大大升高,但仍低于对照.说明本试验的低温弱光已使茄子幼苗发生了膜脂过氧化作用,且对茄子幼苗造成了不可恢复性的伤害.  相似文献   

8.
为了探讨鸡冠花不同耐热品种间光合特性的关系,选用耐热品种世纪绿叶和不耐热品种世纪铜叶为研究对象,在室外高温条件下系统地研究二者的光合特性.结果表明:2 品种鸡冠花的净光合速率和光合有效辐射的日变化均呈单峰曲线,且变化趋势相似且同步,净光合速率和光合有效辐射成正相关,表现为阳性植物特征,但耐热品种世纪绿叶的净光合速率低于世纪铜;气孔导度与净光合速率、蒸腾速率、光合有效辐射和胞间CO2浓度成正相关;在正午12:00时高光照、高叶温条件下,耐热品种世纪绿能在较大范围内维持相对较高的光合效率,世纪绿的光饱和点、光补偿点显著高于世纪铜,二者的光饱和点分别为1500 μmol·m-2·s-1和1000 μmol·m-2·s-1,光补偿点分别为39.3μmol·m-2·s-1和37.1μmol·m-2·s-1;而CO2饱和点分别为1000 μmol/mol和850 μmol/mol,CO2补偿点分别为112. μmol/mol和100.3 μmol/mol.为鸡冠花栽培提供了理论依据.  相似文献   

9.
为了研究珙桐叶片光合特征及其与环境因子的相互关系,对珙桐的引种驯化及资源保护提供重要的理论依据,采用美国产Li-6400型便携式光合测定系统,测定了珙桐叶片的光合作用日变化以及光响应曲线。结果表明:珙桐叶片的表观光量子速率0.09μmol/mol,暗呼吸速率1.31μmol.m-2.s-1,光补偿点22.01μmol.m-2.s-1,光饱和点465.18μmol.m-2.s-1;珙桐叶片的净光合速率、蒸腾速率和气孔导度的日变化曲线均呈双峰曲线,存在明显的"午休"现象;珙桐叶片净光合速率与气孔导度、蒸腾速率呈极显著正相关;气孔导度和蒸腾速率是影响珙桐光合速率的生理因子。  相似文献   

10.
《河西学院学报》2016,(2):65-70
在大田种植条件下,测定白菜型冬油菜陇油6号、陇油7号、陇油8号、陇油9号、天油4号、天油7号和宁油4号幼苗叶片光合和叶绿素荧光参数等指标.结果表明:气温为-10℃时,陇油7号幼苗叶片净光合速率(Pn)、瞬时光能利用率(LUE)、瞬时羧化效率(CE)和瞬时水分利用效率(WUE)最低依次为0.40μmol·CO_2m~(-2)·s~(-1)、0.3216μmolCO_2·mmol~(-1)、0.0010molCO_2m~(-2)·s~(-1)和2.2015μmolCO_2mmol~(-1)H_2O,稳态荧光产量(Fs)、光适应下最大荧光(Fm')和PSII电子传递速率(ETR)最低依次为63.2、85.4和0.8375.在温度降低过程中,超强抗寒白菜型冬油菜品种陇油7号幼苗的光合特性弱于其他白菜型冬油菜品种.  相似文献   

11.
汉字倒说     
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。  相似文献   

12.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

13.
钱生钱!     
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了  相似文献   

14.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

15.
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.  相似文献   

16.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

17.
现在,我们可以没有面包,没有钱,没有房子,没有车子……但我们唯独不能丢失的是高尚的情操,笃定的信念,还有,满满的希望!  相似文献   

18.
Using virtual reality for interactive design gives a designer an intuitive vision of a design and allows the designer to achieve a viable, optimal solution in a timely manner. The article discusses the process of making the Virtual Reality System of the Humble Administrator's Garden. Translating building data to the Virtual Reality Modeling Language (VRML) is by far unsatisfactory. This creates a challenge for computer designers to do optimization to meet requirements. Five different approaches to optimize models have been presented in this paper. The other methods are to optimize VRML and to reduce the file size. This is done by keeping polygon counts to a minimum and by applying such techniques as object culling and level-ofdetail switching.  相似文献   

19.
钱微 《华章》2007,(3):124-124
The awareness of individualism can be traced back to the period of American Revolution when the Declaration of Independence was produced.It expressed basic beliefs concerning freedom,equality,democracy,privacy and the relationship between people and government,which were exactly what the philosophy of individualism mostly dealt with at that time.This paper is to exploit the essence of individualism by analyzing the Declaration .The analysis enables us to reconsider its significance to the issue of America human rights and foreign policies.  相似文献   

20.
裴水妹 《华章》2007,(11):196
Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.  相似文献   

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