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21.
In this study, the effects of potassium doses (control, 150, 300 and 450?mg K2SO4 kg?1) and salt stress (control, 100?mM NaCl) on the yield and some element content of four medicinal and aromatic (Coriandrum sativum, Anethum graveolens, Ocimum basilicum and Foeniculum vulgare) plants were investigated in climate chamber. Both salinity and K fertiliser levels affected the fresh and dry weight of all evaluated plants. Anethum graveolens, Ocimum basilicum species are more sensitive to salinity, particularly at the vegetative productive stages. The highest fresh and dry weights of leaves, stems, roots and herb in Coriandrum sativum and Foeniculum vulgare species was observed in 300?mg?kg?1 fertiliser applications. In general, there was a relatively consistent and positive correlation between root element content and aerial parts element content. The result of the present study showed that NaCl treatment caused an increase in Na+ concentration, and a decrease in K+ and Ca+2 concentration in Coriandrum sativum, Anethum graveolens, Ocimum basilicum and Foeniculum vulgare. There was an interaction between K2SO4 application and salinity effects on Na+ concentration in the all evaluated plants. Given the experimental results, especially Foeniculum vulgare and Coriandrum sativum species were the most resistant to salt stress.  相似文献   
22.
【目的】研究大果榛子黄化萌条扦插苗成活率和生根质量,有效提高黄化萌条的利用率。【方法】以大果榛子品种新榛1号、新榛2号和新榛3号的黄化萌条作为试验材料,研究不同浓度吲哚丁酸(IBA)对其扦插生根率、根生长量特征参数和地上部分生长特征参数的影响,采用隶属函数进行综合评价。【结果】不同浓度IBA对大果榛子不同品种黄化萌条扦插生根率、根生长量特征参数和地上部分生长特征参数的影响有所差异。IBA浓度为5 mmol/L时,新榛1号的生根范围、单株新梢数、单株新梢长度和新梢饱满芽数均最高;新榛2号的生根率、生根指数和单株根数均最高;新榛3号的单株根长、平均根粗和生根范围茎粗最高。IBA浓度为7.5 mmol/L时,新榛1号的单株根长、生根范围、单株新梢数、单株新梢长度和新梢饱满芽数均最高;新榛2号的生根率、生根指数和单株根数均最高;新榛3号的单株根粗和生根范围茎粗均最高。IBA浓度为10 mmol/L时,新榛1号的单株根长、生根范围和新梢饱满芽数均最高;新榛2号的单株根数最高;新榛3号的生根率、生根指数、平均根粗、生根范围茎粗、单株新梢数和单株新梢长度均最高。相关性分析得知,单株根数与单株根长,平均根粗与生根范围中部茎粗间的相关性均达极显著水平,相关性系数(R)分别为-0.897和0.911;生根范围与单株新梢数、单株新梢长度和新梢饱满芽数,生根范围茎粗与单株新梢长度间的相关性系数达显著水平,相关性系数分别为0.750、0.771、0.749和0.753。【结论】新榛1号黄化萌条在IBA速浸浓度为5 mmol/L处理后的性状综合表现较好(隶属函数平均得分值为0.64),新榛2号黄化萌条扦插在IBA速浸浓度为7.5 mmol/L处理后的性状综合表现较好(隶属函数平均得分值为0.73),新榛3号黄化萌条在IBA速浸浓度为10 mmol/L处理后的性状综合表现较好(隶属函数平均得分值为0.70)。  相似文献   
23.
温度对新疆鬣蜥热能代谢及甲状腺素含量的影响   总被引:3,自引:0,他引:3  
以新疆鬣蜥(Agamastoliczkana)为材料,当环境温度分别是低温(5±0.5℃)、室温(15±0.5℃)和高温(30±0.5℃)时,对基础代谢率和甲状腺素(T3,T4)含量进行测定。结果表明,新疆鬣蜥基础代谢率和甲状腺素含量与环境温度正相关,处在低温、室温、高温时,基础代谢率分别为15.82±0.77(S.E)mLO2·kg-1h-1,26.65±2.28(S.E)mLO2·kg-1h-1,69.89±3.43(S.E)mLO2·kg-1h-1。血浆甲状腺素(T3)分别为0.12±0.01(S.E)ng/mL,0.21±0.07(S.E)ng/mL,0.28±0.13(S.E)ng/mL;(T4)分别为3.63±0.58(S.E)ng/mL,8.73±1.1(S.E)ng/mL,21.81±1.82(S.E)ng/mL。同时发现新疆鬣蜥基础代谢率和甲状腺素含量与其活动程度一致。  相似文献   
24.
为研究不同产业选择对于产业减贫的效果以及合作社如何通过不同产业选择带动农户持续减贫,开展了对南疆S县K乡合作社产业减贫的典型调研和案例分析.结果表明,不同产业产品属性特征、附加收益特征、技术难度和市场风险特征对农户减贫效果存在显著差异.基于结论,从合作社产业选择要注重产品属性、产品附加收益特征属性、技术难度和市场风险特...  相似文献   
25.

In the present study, wild orchardgrass ( Dactylis glomerata L.) collected from four different locations (Oltu, Olur, Uzundere and Uluba < ) of Erzurum (Turkey) were used to investigate various electrophoretic analyses within and between four ecotypes based on peroxidase (PRX), polyphenol oxidase (PPO) and malate dehydrogenase (MDH) enzymes. Four natural populations of Dactylis glomerata showed genetic variability within and among ecotypes based on similarities and polymorphism of isoenzyme bands. In addition, a dendogram analysis was made according to band patterns indicating that ecotypes could be grouped showing characteristics in relation to each other, notably Oltu-Uluba < and Olur-Uzundere. However, the degree of relationship of Oltu-Uluba < (6 units) was higher than Olur-Uzundere (12 units).  相似文献   
26.
In this study, the pharmacokinetics of moxifloxacin (5 mg/kg) was determined following a single intravenous administration of moxifloxacin alone and co-administration with diclofenac (2.5 mg/kg) or flunixin meglumine (2.2 mg/kg) in sheep. Six healthy Akkaraman sheep (2 ± 0.3 years and 53.5 ± 5 kg of body weight) were used. A longitudinal design with a 15-day washout period was used in three periods. In the first period, moxifloxacin was administered by an intravenous (IV) injection. In the second and third periods, moxifloxacin was co-administered with IV administration of diclofenac and flunixin meglumine, respectively. The plasma concentration of moxifloxacin was assayed by high-performance liquid chromatography. The pharmacokinetic parameters were calculated using a two-compartment open pharmacokinetic model. Following IV administration of moxifloxacin alone, the mean elimination half-life (t1/2β), total body clearance (ClT), volume of distribution at steady state (Vdss) and area under the curve (AUC) of moxifloxacin were 2.27 hr, 0.56 L h−1 kg−1, 1.66 L/kg and 8.91 hr*µg/ml, respectively. While diclofenac and flunixin meglumine significantly increased the t1/2β and AUC of moxifloxacin, they significantly reduced the ClT and Vdss. These results suggest that anti-inflammatory drugs could increase the therapeutic efficacy of moxifloxacin by altering its pharmacokinetics.  相似文献   
27.
旨在基于RNA-Seq技术对塔里木马鹿毛色相关基因进行筛选及分析。采用Illumina Hi Seq TM2000测序平台对塔里木马鹿和天山马鹿的皮肤组织进行转录组测序,所得序列经质控、组装后比对到NR、Swiss-Prot、COG、KOG、KEGG、GO和Pfam数据库中注释,并对差异表达基因进行筛选、功能注释和富集分析。结果表明,测序获得25 038个有注释信息的Unigenes,比对分析显示,塔里木马鹿与天山马鹿有922个差异表达基因,其中上调表达基因495个,下调表达基因427个;GO功能富集分析结果显示,568个差异表达基因富集到61个GO条目上,分别参与了生物学过程、细胞组分及分子功能;KEGG代谢通路富集分析发现,在差异表达基因中富集最显著的代谢通路是ECM-受体相互作用。利用实时荧光定量PCR(qRT-PCR)方法分析与塔里木马鹿毛色相关的7个候选基因的转录水平变化来验证转录组测序结果的准确性和可靠性,这些基因的表达趋势与转录组测序结果相一致。ECM-受体相互作用、蛋白质消化与吸收、PI3K-Akt信号通路及与黑色素合成相关的酪氨酸等通路可能与塔里木马鹿的毛色有关;候选基因MITFGgt1、VDRPTPRFCⅡTAARPC5L、POMC等可能在塔里木马鹿毛色形成过程中发挥重要作用。本研究结果为今后塔里木马鹿毛色相关基因的分子调控机制方面及挖掘潜在的新基因提供了丰富的试验数据。  相似文献   
28.
以于田-且末绿洲1970年(MSS)、1990年(TM)、2005年(ETM)遥感影像和20世纪50年代地形图为主要数据源,在ENVI软件平台支持下,对研究区进行剪切、配准、解译、分类处理,得出分类图和基础空间信息;在此基础上,对比分析了两个绿洲30a以来绿洲面积、耕地变化和经济发展等因素影响下的动态变化与扩张特征。结果表明:30a以来,且末绿洲沿车尔臣河往外缘扩张,扩张特征主要是"跳跃式"模式;于田绿洲沿克里雅河往外缘扩张,其扩张特征主要是"摊饼式"模式。耕地变化上,两个绿洲历年耕地空间变化特征基本相同,两者变化趋势为增长-减少-增长的波动状态。于田-且末绿洲第一产业所占比重基本相似,二、三产业的增长幅度与速度且末绿洲快于于田绿洲。分析可知,绿洲面积、耕地变化和经济的发展都推进绿洲的扩张,但绿洲扩张的同时出现绿洲外部的荒漠化和内部的盐碱化问题,因此为了防止绿洲综合功能的退化,对绿洲进行动态监测势在必行。  相似文献   
29.
The clearing of Mediterranean maquis along with the creation of new pasture land has been an important factor of soil and land degradation in the Mediterranean region. The present research compared soil aggregates and their intraporosity in paired pasture/maquis plots in central E Sardinia (Italy), to study the impact of land use change on soil structure. Undisturbed surface horizons were sampled for thin‐section analysis. Aggregate shape was compared and intraporosity was studied for representative aggregates at different depths. Furthermore, the interaction of root activity and grazing under pasture and maquis cover was discussed. The outcomes revealed a complex interplay of trampling and root activity effects. A decrease (–44%) in total voids (regular pores), along with higher aggregate regularity, was observed under pasture in the 0–2 cm layer, and an increase (+261%) in 50–100 μm planar (elongated) pores was determined in the 2–4 cm layer, suggesting a possible surface compaction due to trampling and an increased subsurface fine root activity by the grassland vegetation.  相似文献   
30.
Disease development in plants requires a susceptible host, a virulent pathogen, and a favourable environment. Oomycete pathogens cause many important diseases and have evolved sophisticated molecular mechanisms to manipulate their hosts. Day length has been shown to impact plant–oomycete interactions but a need exists for a tractable reference system to understand the mechanistic interplay between light regulation, oomycete pathogen virulence, and plant host immunity. Here we present data demonstrating that light is a critical factor in the interaction between Arabidopsis thaliana and its naturally occurring downy mildew pathogen Hyaloperonospora arabidopsidis (Hpa). We investigated the role of light on spore germination, mycelium development, sporulation, and oospore formation of Hpa, along with defence responses in the host. We observed abundant Hpa sporulation on compatible Arabidopsis under day lengths ranging from 10 to 14 hr. In contrast, exposure to constant light or constant dark suppressed sporulation. Exposure to constant dark suppressed spore germination, mycelial development, and oospore formation, whereas exposure to constant light stimulated these three stages of development. A biomarker of plant immune system activation was induced under both constant light and constant dark. Altogether, these findings demonstrate that Hpa has the molecular mechanisms to perceive and respond to light and that both the host and pathogen responses are influenced by the light regime. Therefore, this pathosystem can be used for investigations to understand the molecular mechanisms through which oomycete pathogens like Hpa perceive and integrate light signals, and how light influences pathogen virulence and host immunity during their interactions.  相似文献   
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