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1.
12种龙胆科植物胚胎学资料的聚类分析   总被引:4,自引:0,他引:4  
本文在平均欧氏距离系数基础上,运用UPGMA法,对12种龙胆科植物胚胎学资料进行了Q型聚类分析,聚类结果如下:(1)在树系图上,12种龙胆科植物明显分为4大类,其中第一大类包括椭圆叶花锚和四数獐牙菜,双蝴蝶属的峨眉双蝴蝶和假龙胆属的黑边假龙胆则分别单独聚为第三、第四类,其它8种植物共聚为第二大类;(2)獐牙菜属的4个种在胚胎学性状上明显分化3支,其中抱茎獐牙菜、西南獐牙菜与喉毛花聚为1支,红直獐牙菜与湿生扁蕾另聚1支,四数獐牙菜与椭圆叶花锚聚为1大类:(3)龙胆属的3个种与抱茎獐牙菜、西南獐牙菜、红直獐牙菜以及喉毛花、湿生扁蕾等共聚为一大类,且存在一定的分化,东北龙胆和线叶龙胆关系密切,条纹龙胆与前两者差异较大.聚类分析结果支持将双蝴蝶属、扁蕾属以及喉毛花属作为属级处理的意见,同时认为扁蕾属、喉毛花属和花锚属在系统学上与獐牙菜属有着密切的联系,獐牙菜属在低等类群中分化出扁蕾属,在高等类群中分化出花锚属,在中等进化的类群中分化出喉毛花属,而扁蕾属则进一步分化出龙胆属.  相似文献   

2.
超声波处理抱茎獐牙菜种子萌发试验研究   总被引:1,自引:0,他引:1  
为促进抱茎獐牙菜种子萌发。采用超声波、超声波和赤霉素相结合处理种子,研究其对抱茎獐牙菜种子萌发能力的影响。结果表明:超声波处理20~50 min,对种子的萌发均有促进作用,其中以超声波处理35 min效果较好,种子的发芽势和发芽率比对照相对提高59.3%和17.8%,处理种子比对照提前2~3 d发芽;超声波和赤霉素共同作用种子,产生了相长的效果,其中以超声波作用35 min、赤霉素浓度1 200 mg/kg、浸种18 h效果较好,种子的发芽势和发芽率比对照相对提高54.5%和16.5%。超声波、超声波和赤霉素相结合处理能够明显促进抱茎獐牙菜种子萌发。  相似文献   

3.
不同药剂浸种对芹菜种子发芽的影响   总被引:4,自引:0,他引:4  
通过不同药剂处理对芹菜种子,结果表明:321mg.mL-1的PEG(6000)浸种极显著地提高了芹菜种子的发芽率、发芽势以及种子活力;NaCl、CaCl2及低浓度的赤霉素(0.01~0.1mg/mL)混合液浸种也具有相同的效果;而混合液中高浓度的赤霉素(1 mg/mL)浸种则会降低种子的发芽率、发芽势以及种子活力。  相似文献   

4.
目的:采用HPLC和电喷雾质谱联用技术分析西藏秦艽花与川西秦艽花中的7种化学成分.方法:液相色谱条件色谱柱:Agilent Zorbax ODS(5μm,4.6 mm×250 mm);流动相:乙腈(A)-0.4%醋酸水溶液(B)进行梯度洗脱;体积流速为0.4 m L/min;检测波长254 nm;电喷雾质谱采用负离子模式采集.结果:采用HPLC-ESI-MS~n法分析西藏秦艽花和川西秦艽花中的7种成分,分别为獐牙菜苦苷、异牡荆黄素、落干酸、龙胆苦苷、异荭草苷、獐牙菜苷及6'-O-β-D-葡萄糖基龙胆苦苷.结论:HPLC-ESI-MS~n联用分析法可以鉴定分析西藏秦艽花和川西秦艽花中的7种成分,为该属植物成分的质量控制提供了科学依据.  相似文献   

5.
CaCl2和甘油对瓜尔豆种子活力的影响   总被引:1,自引:0,他引:1  
用不同浓度的CaCl2和甘油溶液在15℃条件下处理瓜尔豆种子24h,放人(15±1.5)℃的发芽箱中发芽.结果表明0.5%CaCl2溶液极显著提高了瓜尔豆种子的发芽率、发芽势、发芽指数和活力指数;1%的甘油和1%CaCl2也有提高种子活力的趋势,但效果不显著.  相似文献   

6.
以不同浓度的3种激素(GA3、NAA、6—BA)处理基础发芽率约为20%和60%的水稻陈种子,研究其对陈年水稻种子发芽势和发芽率的影响。结果发现,GA,对2种水稻陈种子的发芽势和发芽率影响微弱,NAA极显著的降低了2种水稻陈种子的发芽势和发芽率,6—BA处理后前者种子发芽率显著下降,后者种子发芽势极显著下降。  相似文献   

7.
以外来入侵物种空心莲子草与国家珍稀植物海菜花为研究对象,采用培养皿滤纸法研究不同浓度空心莲子草浸提液对海菜花种子萌发及幼苗生长的影响。结果表明:海菜花种子发芽势、发芽率随浸提液浓度增高先升高后降低;当浸提液浓度为50%、30%时,种子发芽势与发芽率分别达到27.5%、82.5%;浸提液浓度为50%时对海菜花种子发芽势促进作用极显著(P0.0001);浸提液浓度为30%时对海菜花种子发芽率促进作用极显著(P0.0001)。浸提液浓度分别低于30%、10%时,海菜花幼苗的苗长与鲜重、根长均表现为促进作用。  相似文献   

8.
为探究加拿大一枝黄花(Solidago canadensis)在不同浓度下对盐胁迫和铝胁迫的耐受性,以加拿大一枝黄花为材料,采用室内生物测定的方法,利用 0、200、400、800、1600、3200 mg/L 不同浓度 Na Cl 和 AlCl3 溶液处理加拿大一枝黄花种子,并对其萌发特性进行比较研究。结果表明:(1)加拿大一枝黄花种子的发芽率随着Na Cl 浓度的增加而降低,与对照相比,800 mg/L 浓度的 Na Cl 溶液对其发芽率和发芽势产生显著抑制作用(P <0.05),当浓度为 1600 ~ 3200mg/L 时,发芽率和发芽势极显著降低(P < 0.01),当浓度为 800 ~ 3200 mg/L 时,加拿大一枝黄花发芽指数极显著降低(P < 0.01);(2)加拿大一枝黄花种子发芽率随着 AlCl3 浓度的增加而降低,与对照相比,200 ~ 3200mg/L 的 AlCl3 溶液对其发芽率、发芽势及发芽指数受到极显著抑制作用(P < 0.01)。(3)加拿大一枝黄花种子对盐胁迫...  相似文献   

9.
高寒植物功能性状对种子萌发率与出苗率的影响   总被引:1,自引:0,他引:1  
为了研究高寒植物功能性状对种子萌发率与出苗率的影响,对30种高寒植物进行萌发试验、盆栽试验以及测定包括百粒重、种子数、繁殖分配、比叶面积、生物量、高度在内的功能性状,并对萌发率、出苗率与功能性状进行了相关分析和回归分析。结果表明:萌发率与种子数呈极显著正相关(P 0. 01),与其余功能性状无显著相关性;出苗率与萌发率、生物量及高度均表现出极显著正相关(P 0. 01)。萌发率与种子数之间存在极显著线性关系(P 0. 01);出苗率与种子数之间存在显著线性关系(P 0. 05),出苗率与生物量、高度和萌发率之间存在极显著线性关系(P 0. 01)。因此,用植物功能性状预测其种子的萌发率与出苗率是可行的。  相似文献   

10.
以濒危植物千果榄仁种子为试材,研究了种子经过休眠破除处理和常温储藏后,不同外源激素(赤霉素、萘乙酸)和培养温度对种子发芽的影响.结果表明:生长调节剂种类和质量浓度对种子发芽率的影响极显著(P<0.01),储藏方式和培养温度对种子发芽率的影响不明显(P>0.05),影响程度由大到小依次为生长调节剂种类、生长调节剂质量浓度、培养温度、储藏方式;种子用相同质量浓度的赤霉素、萘乙酸生长调节剂处理后,在不同培养温度下培养,种子发芽率从高到低依次为休眠破除处理变温培养、休眠破除处理恒温培养、常温储藏变温培养、常温储藏恒温培养;千果榄仁种子发芽最优条件是在种子采收后,低温4℃处理30 d,用质量浓度为40 mg/L的赤霉素浸种且在光照变温15~25℃培养箱内培养.  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.
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   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  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.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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