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三色堇(Viola tricolor L.)生物学特性及栽培管理 被引量:14
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作者 王晓磊 胡宝忠 《东北农业大学学报》 CAS CSCD 2008年第6期132-135,共4页
三色堇是重要的园林绿化植物,近年来对其研究较多,文章从三色堇的生物学特性、栽培及病虫害防治方面进行概述。
关键词 三色堇 生物学特性 栽培 病虫害防治
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三色堇(Viola tricolor L.var.hortensis DC.)花蜜腺的亚显微结构 被引量:1
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作者 沈敏健 季玲妹 《华东师范大学学报(自然科学版)》 CAS CSCD 1991年第1期102-108,共7页
本文用透射和扫描电镜对三色堇花不同发育时期蜜腺进行了研究,了解到该植物花蜜中糖份主要来源于蜜腺分泌组织自身的光合产物;内质网参与了前蜜的加工和运输;质膜的啜入和反啜入作用是分泌组织细胞间前蜜传递的主要方式;蜜最后通过表皮... 本文用透射和扫描电镜对三色堇花不同发育时期蜜腺进行了研究,了解到该植物花蜜中糖份主要来源于蜜腺分泌组织自身的光合产物;内质网参与了前蜜的加工和运输;质膜的啜入和反啜入作用是分泌组织细胞间前蜜传递的主要方式;蜜最后通过表皮细胞质膜的分子渗透作用而排放出体外;表皮细胞向外的指状突起是蜜汁分泌的主要部位. 展开更多
关键词 三色堇 亚显微结构 密腺 植物
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Mechanism of Anti-tumor Effects of Viola Medicinal Materials Based on Network Pharmacology and Molecular Docking
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作者 Xiaoyong HE Liniu SHAMA +4 位作者 Dongmei SHA Shuaicong NI Jing WEN Xinjia YAN Yuan LIU 《Medicinal Plant》 2024年第3期9-15,共7页
[Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through n... [Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through network pharmacological analysis,molecular docking simulation experiments and in vitro experiments,the main components and corresponding targets of Viola were screened out,and their anti-tumor signaling pathways were confirmed.MTT colorimetric assay was used to investigate the inhibitory effect of different extraction layers of Viola on the growth of tumor cells.[Results]18 anti-tumor active components such as 2α,19α-Dihydroxyursolic acid,Corlumine,Madolin U,Trifolirhizin and etc.,and 52 action targets such as PTGS2,PTGS1,P2RX7,MMP1,and GABRB3,and anti-tumor signaling pathways were confirmed.The results of molecular docking showed that all the selected Viola compounds had good binding activity.The results of MTT colorimetric assay showed that the petroleum ether layer and n-butanol layer had a good inhibitory effect on the growth of tumor cell lines.[Conclusions]Viola medicinal materials have the potential of anti-tumor,triterpenoids and flavonoids may be the main active components,and the petroleum ether layer and n-butanol layer have better inhibitory effect on the growth of tumor cells. 展开更多
关键词 viola MEDICINAL materials ANTI-TUMOR Network PHARMACOLOGY Molecular DOCKING MTT
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堇菜属Viola植物资源的园林开发前景探讨 被引量:13
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作者 段春燕 候小改 +1 位作者 张赞平 李连方 《中国农学通报》 CSCD 2004年第5期185-186,共2页
介绍了中国堇菜属野生植物的资源数量、分布及观赏特性,并分析了堇菜属植物的园林开发前景。
关键词 堇菜属viola植物资源 园林应用 生物学特性 观赏特性
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Comparative Analysis on Cadmium Tolerance and Antioxidant Enzymatic Activities of Two Viola Species 被引量:2
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作者 张军 于沛 +1 位作者 杨兵 廖斌 《Agricultural Science & Technology》 CAS 2011年第8期1195-1198,1216,共5页
[Objective]This study aimed at exploring the physiological properties of the known Cd hyperaccumulator Viola baoshanensis and the control plant Viola inconspicua to cadmium stress.[Method]After a hydroponic experiment... [Objective]This study aimed at exploring the physiological properties of the known Cd hyperaccumulator Viola baoshanensis and the control plant Viola inconspicua to cadmium stress.[Method]After a hydroponic experiment carried in a greenhouse,plant Cd accumulations,root elongation rates,MDA contents,and antioxidant enzyme activities were determinined.[Result]Both Viola baoshanensis and Viola inconspicua showed high levels of Cd uptake growing in Cd-supplemented solution of 300 μmol/L for 12 d with Cd accumulations of 2 595 and 3 330 mg/kg in the shoots,respectively.In the cultural solution supplemented with 300 μmol/L of Cd,the root elongation rates were not affected and the MDA contents decreased significantly in Viola baoshanensis,while the root elongation rates were significantly inhibited and the MDA contents increased remarkably in Viola inconspicua,which indicated that Viola baoshanensis had the higher Cd tolerance.The superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)activities of two Viola species were not linearly related to the middle and low Cd-supplemented concentrations(5,50 μmol/L)and had attained the tiptop in cultural solution supplemented with 100 or 300 μmol/L of Cd but declined in cultural solution supplemented with 500 μmol/L of Cd,suggesting that the contribution of antioxidative enzymes was limited to the Cd tolerance of Viola plants.The Viola inconspicua showed a strong adaptability to the middle and low concentrations of Cd.[Conclusion]Viola species could be used as potential plant resources for the phytoremediation of agriculture areas polluted with low and even middle levels of Cd. 展开更多
关键词 Cadmium(Cd)tolerance Antioxidant enzyme viola baoshanensis viola inconspicua
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宝山堇菜(Viola baoshanensis)镉胁迫下的光合作用 被引量:35
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作者 邓培雁 刘威 韩博平 《生态学报》 CAS CSCD 北大核心 2007年第5期1858-1862,共5页
利用荧光成像技术研究了自然生长状态下宝山堇菜、紫花地丁镉含量与光合作用间的关系。野外调查表明,宝山堇菜、紫花地丁镉含量差异显著,地上部分镉含量分别为867mg/kg和2mg/kg,相差近450倍;镉转运系数、富集系数,宝山堇菜均大于1,紫花... 利用荧光成像技术研究了自然生长状态下宝山堇菜、紫花地丁镉含量与光合作用间的关系。野外调查表明,宝山堇菜、紫花地丁镉含量差异显著,地上部分镉含量分别为867mg/kg和2mg/kg,相差近450倍;镉转运系数、富集系数,宝山堇菜均大于1,紫花地丁均小于1。叶绿素荧光参数,宝山堇菜Fm、Ik、Pm均显著低于紫花地丁(p=0.05);两种植物间Fo、Fv/Fm、α均无显著差异。紫花地丁地上部分镉含量与叶绿素荧光参数的相关性较低,宝山堇菜地上部分镉含量与Fm、Pm、Ik达到极显著负相关。Fv/Fm,宝山堇菜、紫花地丁均在0.8左右,与镉的相关性较低,表明其光合作用没有受到镉胁迫。但是,宝山堇菜Fm显著低于紫花地丁,而且与镉呈负相关,表明宝山堇菜叶片Fm会随镉含量的增加而降低,预示镉可能会造成宝山堇菜光系统Ⅱ叶绿素结构破坏或者抑制其电子传递。参数Ik和Pm在两种植物间差异显著及其与宝山堇菜地上部分镉含量显著负相关反映宝山堇菜光耐受能力和电子传递能力在镉胁迫下逐渐减弱。初始斜率α始终维持在较高水平,说明镉胁迫并未对宝山堇菜捕光系统造成显著伤害。结合Fm值的变化和快速光曲线中荧光参数的变化推断镉最有可能会造成宝山堇菜电子传递能力的减弱。 展开更多
关键词 宝山堇菜 紫花地丁 光合作用 快速光曲线
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宝山堇菜(Viola baoshanensis)、紫花地丁(V.yedoensis)光合异质性比较 被引量:8
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作者 邓培雁 刘威 +1 位作者 韩博平 韩志国 《生态学报》 CAS CSCD 北大核心 2007年第7期2983-2989,共7页
利用荧光成像技术,研究了特定和不同光合有效辐射下,宝山堇菜(Viola baoshanensis)、紫花地丁(V.yedoensis)不同叶龄(幼叶和成熟叶片)叶片纵向(叶基、叶中部、叶尖)间的光合异质性特征。特定光化光照射下,两种堇菜不同叶龄的Fv/Fm、Φp... 利用荧光成像技术,研究了特定和不同光合有效辐射下,宝山堇菜(Viola baoshanensis)、紫花地丁(V.yedoensis)不同叶龄(幼叶和成熟叶片)叶片纵向(叶基、叶中部、叶尖)间的光合异质性特征。特定光化光照射下,两种堇菜不同叶龄的Fv/Fm、ΦpsⅡ、qP、PS/50和Abs在叶尖、叶中部、叶基间呈依次降低趋势,NPQ/4和qN变化趋势与之相反。Fv/Fm、ΦpsⅡ和Abs在两种堇菜不同叶龄的叶片纵向间均没有显著性差异,NPQ/4和qN均显示宝山堇菜不同叶龄的叶片纵向间存在显著差异;但NPQ/4和qN分别显示紫花地丁成熟叶和幼叶叶片的叶尖和叶基处差异显著。qP的显著差异只存在于宝山堇菜幼叶的叶尖和叶基处,PS/50在两种植物幼叶纵向间均有显著差异。快速光曲线的变化中,两种堇菜α由叶尖向叶基下降幅度不明显,幼叶纵向间Pm差异显著,成熟叶叶尖处Pm显著高于叶中部和叶基。两种堇菜成熟叶叶尖处Ik显著高于叶中部和叶基,宝山堇菜幼叶纵向间Ik差异显著,而紫花地丁幼叶纵向间Ik差异不显著。以上结果反映出两种堇菜叶片纵向间Fv/Fm和ΦpsⅡ具有较高的均质性,Fv/Fm和ΦpsⅡ的下降受到NPQ/4、qN、qP、PS/50和Abs的综合影响,但Fv/Fm和ΦpsⅡ的变化与NPQ/4、qN、qP、PS/50的显著变化并不一致。叶龄对两种堇菜叶片纵向间α影响不显著,对Pm影响显著,α的小幅下降反映两种堇菜叶片纵向间捕光能力基本相同。叶片纵向间Ik的显著差异受叶龄和植物种类的综合影响。 展开更多
关键词 宝山堇菜 紫花地丁 荧光成像技术 光合异质性
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RAPD在三色堇(Viola wittrockiana)自交系遗传关系研究及杂种优势预测中的应用 被引量:16
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作者 王健 包满珠 《武汉植物学研究》 CSCD 北大核心 2007年第1期19-23,共5页
用RAPD技术分析了18个三色堇(Viola wittrockiana)自交系的遗传多样性。21个随机引物扩增了167条带,其中127条具多态性,显示自交系间存在较大的遗传变异。用UPGMA法可将自交系聚为五大类,其分类结果与花径和材料来源地基本一致。以其中... 用RAPD技术分析了18个三色堇(Viola wittrockiana)自交系的遗传多样性。21个随机引物扩增了167条带,其中127条具多态性,显示自交系间存在较大的遗传变异。用UPGMA法可将自交系聚为五大类,其分类结果与花径和材料来源地基本一致。以其中的5个自交系进行双列杂交试验,研究了RAPD遗传距离与三色堇杂交后代10个性状杂种优势的关系,实验结果表明:RAPD遗传距离仅与花数达到0.1的显著水平,而与其它8个性状杂种优势的相关性不显著;用RPAD遗传距离预测三色堇的花数杂种优势具有一定的可靠性,但用于对其它性状杂种优势的预测目前是不可行的。 展开更多
关键词 三色堇 RAPD 遗传关系 杂种优势
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宝山堇菜(Viola baoshanensis)和紫花地丁(V. yedoensis)叶绿素荧光参数的日变化 被引量:5
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作者 邓培雁 刘威 +1 位作者 邱元凯 曾宝强 《华南师范大学学报(自然科学版)》 CAS 北大核心 2009年第2期96-99,105,共5页
研究了宝山堇菜(Viola baoshanensis)和紫花地丁(V. yedoensis)叶片叶绿素荧光参数的日变化.紫花地丁NPQ呈单峰型增长,宝山堇菜NPQ有先增加,后下降的趋势.2种堇菜rETR首先迅速上升,维持在一个较高水平,然后迅速下降,Ik变化趋势相对一致... 研究了宝山堇菜(Viola baoshanensis)和紫花地丁(V. yedoensis)叶片叶绿素荧光参数的日变化.紫花地丁NPQ呈单峰型增长,宝山堇菜NPQ有先增加,后下降的趋势.2种堇菜rETR首先迅速上升,维持在一个较高水平,然后迅速下降,Ik变化趋势相对一致.紫花地丁Pm和α呈双峰型变化,宝山堇菜有先增加,后下降的变化趋势.相关性显示,宝山堇菜叶片rETR与光合有效辐射呈显著正相关(P<0.05).紫花地丁叶片温度分别与Y、NPQ呈显著负相关和正相关(P<0.05),叶表光合有效辐射与Y、NPQ分别达极显著负相关和正相关(P<0.01),与rETR显著正相关(P<0.05).结果表明,正午时刻2种堇菜光系统Ⅱ遭受了光抑制,热耗散和光呼吸是紫花地丁的重要光保护机制,宝山堇菜通过光呼吸来保护光合机构. 展开更多
关键词 宝山堇菜 紫花地丁 叶绿素荧光 光合作用 日变化
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国产堇菜属(Viola)植物的数量分类学研究 被引量:4
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作者 孙坤 王庆瑞 王漪 《西北师范大学学报(自然科学版)》 CAS 1997年第3期69-73,共5页
应用聚类分析的方法对国产堇菜属植物进行了数量分类研究,根据结合水平探讨了堇菜属中亚属和组的划分,发现须毛柱头亚属和二裂花柱亚属作为同一亚属的不同组处理更为合理.堇菜亚属中多数组的划分与传统分类的结果相一致,但裂叶堇菜... 应用聚类分析的方法对国产堇菜属植物进行了数量分类研究,根据结合水平探讨了堇菜属中亚属和组的划分,发现须毛柱头亚属和二裂花柱亚属作为同一亚属的不同组处理更为合理.堇菜亚属中多数组的划分与传统分类的结果相一致,但裂叶堇菜组和阔鞘堇菜组应合并到合生托叶组中,鳞茎堇菜复合群最好分出另立一组.根据聚类分析结果,并结合形态学特征和地理分布式样的分析,确认西山堇菜和维西堇菜实属同一个种。 展开更多
关键词 中国 堇菜属 聚类分析 数量分类学
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山东堇菜属(Viola)植物的分类学研究 被引量:4
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作者 黄勇 钱关泽 陈汉斌 《山东师范大学学报(自然科学版)》 CAS 1997年第3期311-315,共5页
通过对山东堇菜属植物的详细考查和深入研究,基本查清了该属植物在山东的种类和分布.经研究认为早开堇菜、茜堇菜和紫花地丁应为同种,合并为紫花地丁.最后确认山东堇菜属植物有23种,1亚种,其中6种为山东新纪录.
关键词 堇菜属 分类 山东
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山东堇菜属(Viola)植物花粉形态研究及其分类意义 被引量:4
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作者 黄勇 陈汉斌 《山东师范大学学报(自然科学版)》 CAS 1993年第3期78-82,共5页
通过光学显微镜和扫描电镜观察了山东Viola属20种、亚种的花粉超微结构,探讨了花粉特征的分类意义,研究揭示了各个种花粉粒的大小、形状、萌发孔沟类型及表面纹饰等特征,是研究该属分类的新资料。
关键词 花粉 山东 堇菜属 分类
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在超重核区应用Viola-Seaborg公式研究α衰变寿命 被引量:1
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作者 彭金松 《原子核物理评论》 CAS CSCD 北大核心 2009年第2期112-116,共5页
在超重核区(Z≥104)使用文献[7—9]给出的3组参数应用Viola-Seaborg公式计算了α衰变寿命,所得结果与实验值进行比较,发现其结果与实验值相差较大。为此,利用最小二乘法分别在重核区和超重核区重新对参数进行了拟合,得到的计算结果与实... 在超重核区(Z≥104)使用文献[7—9]给出的3组参数应用Viola-Seaborg公式计算了α衰变寿命,所得结果与实验值进行比较,发现其结果与实验值相差较大。为此,利用最小二乘法分别在重核区和超重核区重新对参数进行了拟合,得到的计算结果与实验值相比符合得较理想,尤其是由超重核得到的参数的结果非常理想。 展开更多
关键词 viola—Seaborg公式 超重核 Α衰变寿命 参数拟合
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Effects of Copper on the Photosynthesis and Oxidative Metabolism of Amaranthus tricolor Seedlings 被引量:8
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作者 KEShi-sheng 《Agricultural Sciences in China》 CAS CSCD 2007年第10期1182-1192,共11页
The objective of the present study was to gain better insight into the physiological mechanisms on the effects of copper (Cu) on photosynthesis and active oxygen metabolism in three-colored amaranth plant (Amaranth... The objective of the present study was to gain better insight into the physiological mechanisms on the effects of copper (Cu) on photosynthesis and active oxygen metabolism in three-colored amaranth plant (Amaranthus tricolor). Three- colored amaranth seedlings were subjected to different Cu levels in soils during the entire experimental period. The parameters of growth, photosynthesis, mineral elements contents, and active oxygen metabolism were investigated using plant physiological methods. The results showed that 2.0 and 4.0 mmol Cu kg^-1 treatments decreased the whole plant biomass to 91 and 73% of the control, respectively. The net photosynthetic rate (Pn) and the stomatal conductance (gs) were similarly reduced in the third leaves of three-colored amaranth seedlings treated with 2.0 and 4.0 mmol Cu kg^-1 soil, respectively. None of the investigated Cu levels decreased the internal CO2 concentration (Ci). The effect of Cu on the potential efficiency of photosystem Ⅱ (Fv/Fm) was negligible, whereas the effect of Cu on the PS Ⅱ quantum efficiency (ΦPS Ⅱ) after plant adaptation in actinic irradiation was more noticeable. On the other hand, decreases in water percentage, contents of photosynthetic pigments and mineral elements including Fe, K, and Mg, and significant increase in the Cu content were observed in the third leaves of Cu-treated plants. Superoxide dismutase (SOD) and peroxidase (POD) activities as well as the proline (Pro) content significantly increased in the third leaves of the three-colored amaranth seedlings treated with 2.0 and 4.0 mmol Cu kg^-1 soil, while catalase (CAT) and ascorbate peroxidase (APX) activities as well as the contents of carotenoid (Car), glutathione (GSH), and ascorbic acid (AsA) decreased, and accompanied by the increases in the contents of hydrogen peroxide (H2O2), superoxide anion (O2^-), and malondialdehyde (MDA), and electrolyte leakage. As a result of the imbalance of active oxygen metabolism, Pn and ΦPS Ⅱ decreased, and peroxidization enhanced under levels of 2.0 and 4.0 mmol Cu kg^-1 soil. Finally, the growth of three-colored amaranth plant was significantly inhibited. 展开更多
关键词 copper toxicity growth PHOTOSYNTHESIS active oxygen metabolism three-coloured amaranth plants (Amaranthus tricolor
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Isolation of a choline monooxygenase cDNA clone from Amaranthus tricolor and its expressions under stress conditions 被引量:14
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作者 MentYL WangYM 《Cell Research》 SCIE CAS CSCD 2001年第3期187-193,共7页
Plants synthesize the osmoprotectant glycine betaine (GB) via choline→betaine aldehyde→glycine be- taine[1]. Two enzymes are involved in the pathway choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BA... Plants synthesize the osmoprotectant glycine betaine (GB) via choline→betaine aldehyde→glycine be- taine[1]. Two enzymes are involved in the pathway choline monooxygenase (CMO) and betaine aldehyde dehydrogenase (BADH). A full length CMO cDNA (1,643bp) was cloned from Amaranthus tricolor. The open reading frame encoded a 442-amino acid polypeptide, which showed 69% identity with CMOs in Spina- cia oleracea L. and Beta vulgaris L. DNA gel blot analysis indicated the presence of one copy of CMO gene in the A. tricolor genome. The expressions of CMO and BADH proteins in A.tricolor leaves significantly increased under salinization, drought and heat stress (42℃), as determined by immunoblot analysis, but did not respond to cold stress (4℃), or exogenous ABA application. The increase of GB content in leaves was parallel to CMO and BADH contents. 展开更多
关键词 Amaranthus tricolor betaine aldehyde dehydrogenase(BADH) choline monooxygenase (CMO) glycine betaine (GB) stress.
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Effects of Different Arbuscular Mycorrhizal Fungi on Physiology of Viola prionantha under Salt Stress 被引量:2
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作者 Yajie Liu Linlin Fang +1 位作者 Wenna Zhao Chunxue Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期55-69,共15页
Arbuscular mycorrhizal(AM)fungi distribute widely in natural habits and play a variety of ecological functions.In order to test the physiological response to salt stress mediated by different AM fungi,Viola prionantha... Arbuscular mycorrhizal(AM)fungi distribute widely in natural habits and play a variety of ecological functions.In order to test the physiological response to salt stress mediated by different AM fungi,Viola prionantha was selected as the host,the dominant AM fungus in the rhizosphere of V.philippica growing in Songnen saline-alkali grassland,Rhizophagus irregularis,and their mixtures were used as inoculants,and NaCl stress was applied after the roots were colonized.The results showed that V.philippica could be colonized by AM fungi in the field and the colonization rate ranged from 73.33%to 96.67%,and Claroideoglomus etunicatum was identified as the dominant AM fungi species in the rhizosphere of V.philippica by morphology combined with sequencing for AM fungal AML1/AML2 target.Inoculation with both the species resulted in the formation of mycorrhizal symbiosis(the colonization rate was more than 70%)and AM fungi significantly enhanced plants’tolerance to salt stress of varying magnitude.Higher activity of antioxidant enzymes and augmented levels of proline and other osmoregulators were observed in AM plants.The content of MDA in CK was higher than that in the inoculations with the stress of 100,200,and 250 mM.All indices except soluble protein content and MDA content were significantly correlated with AM fungal colonization indices.The analysis for different AM fungal effects showed that the mixtures and R.irregularis worked even better than C.etunicatum.These results will provide theoretical support for the exploration and screening of salt-tolerant AM fungi species and also for the application of AM-ornamental plants in saline-alkali urban greening. 展开更多
关键词 Dominant AM fungi species viola philippica salt stress viola prionantha physiological response
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基于运动区域Viola-Jones算法的视频人脸检测 被引量:2
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作者 彭明莎 刘翠响 《电子设计工程》 2015年第21期15-17,共3页
为了进一步提高人脸检测的准确率,本文采用一种基于运动区域的检测方法,该方法主要通过采用帧差法和自适应的滑动平均法相结合的算法,建立提取运动区域的模型,然后通过基于Boxfilter算法的Viola-Jones进行快速人脸检测。自适应的滑动平... 为了进一步提高人脸检测的准确率,本文采用一种基于运动区域的检测方法,该方法主要通过采用帧差法和自适应的滑动平均法相结合的算法,建立提取运动区域的模型,然后通过基于Boxfilter算法的Viola-Jones进行快速人脸检测。自适应的滑动平均法是通过检测光照突变和像素点来实现阈值和更新率的自适应更新,该法提取的前景与帧差法提取的前景进行"与运算"。实验结果表明,该方法可以有效地提取运动区域,从而使人脸检测性能得到进一步的提高,具有一定的应用价值。 展开更多
关键词 帧差法 滑动平均法 viola-Jones算法 Boxfilter算法
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RNA Extraction from Herba Violae Roots with Low-temperature Sectioning Method 被引量:1
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作者 Chun ZHANG Yingyu MAO +2 位作者 Bo LUO Mao LUO Suqun DUAN 《Agricultural Biotechnology》 CAS 2013年第3期33-35,共3页
[ Objective ] This study aimed to investigate the optimal method for extracting RNA from roots of medicinal plant herba violae by comparing the effects of liquid nitrogen grinding method and low-temperature sectioning... [ Objective ] This study aimed to investigate the optimal method for extracting RNA from roots of medicinal plant herba violae by comparing the effects of liquid nitrogen grinding method and low-temperature sectioning method on RNA extraction. [ Method] Roots of herba violae were respectively crushed by using liquid nitrogen grinding method and low-temperature sectioning method to extract RNA. The extraction effects of these two methods were compared based on detec- tion of RNA concentration, purity and integrity and amplification of GAPDH gene by RT-PCR. [Result] The concentration of RNA extracted by liquid nitrogen grinding method and low-temperature sectioning method was 1.21 and 3.57 p^g/~, respectively. Both RNA extracted by these two methods showed two distinct bands after agarose gel electrophoresis. The ratio of brightness of the 28S rRNA to the 18S rRNA bands was greater than 1. PCR amplification showed that the length of GAPDH gene was about 230 bp, which was consistent with the expected result. [ Conclusion ] The experimental results indicated that using low-tempera ture sectioning method to crush the roots of herba violae can meet the needs of most molecular biological experiments including gene cloning and expression analysis, which is an effective and simple method for extracting RNA from plant roots. 展开更多
关键词 Low-temperature sectioning RNA extraction Herba violae roots
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菌株Marasmius tricolor 310b发酵粗酶液对3种染料脱色效果的研究
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作者 王志慧 芦光新 +4 位作者 黄彩霞 王英成 刘炳炎 潘宇睦 郑文珺 《微生物前沿》 2021年第1期81-89,共9页
为探索分离自青藏高原高寒草地产漆酶新真菌菌株Marasmius tricolor 310b对苯甲烷类、蒽醌类和偶氮类染料的脱色效果,采用摇瓶发酵法获得漆酶粗酶液进行脱色实验。结果表明菌株Marasmius tricolor 310b漆酶发酵粗酶液都能够有效的降解... 为探索分离自青藏高原高寒草地产漆酶新真菌菌株Marasmius tricolor 310b对苯甲烷类、蒽醌类和偶氮类染料的脱色效果,采用摇瓶发酵法获得漆酶粗酶液进行脱色实验。结果表明菌株Marasmius tricolor 310b漆酶发酵粗酶液都能够有效的降解溴甲酚绿(苯甲烷类)、茜素红(蒽醌类)、刚果红(偶氮类) 3种染料,但降解效果有所差异,其中,以苯甲烷类染料脱色作用最优。另发现菌株Marasmius tricolor 310b发酵粗酶液对3种染料的降解程度与波长和反应时间有直接关系,随着反应时间的延长,降解效率有不同程度提高。我们的研究初步揭示了新菌株Marasmius tricolor 310b发酵粗酶液对苯甲烷类、蒽醌类、偶氮类具有明显的脱色效果,这一发现对于更新具有脱色效果的真菌资源库有一定的理论支持。 展开更多
关键词 发酵粗酶液 染料 脱色 菌株Marasmius tricolor 310b
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基于Viola-Jones框架人脸检测算法的汽车疲劳驾驶检测 被引量:4
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作者 吴雪颖 吴才硕 +1 位作者 黄文聪 覃舒琳 《广西科技大学学报》 2021年第1期49-54,共6页
疲劳驾驶导致汽车交通事故逐年增加,为了提升驾车的安全性,需对驾驶员疲劳状态实时监测并及时提醒.为了提高疲劳驾驶判断效率及准确率,本文运用Viola-Jones框架特征矩阵进行人脸预判断;预判断过程中为了减少Haar值计算量并提高人脸识别... 疲劳驾驶导致汽车交通事故逐年增加,为了提升驾车的安全性,需对驾驶员疲劳状态实时监测并及时提醒.为了提高疲劳驾驶判断效率及准确率,本文运用Viola-Jones框架特征矩阵进行人脸预判断;预判断过程中为了减少Haar值计算量并提高人脸识别速度,采用Adaboost算法和级联分析,剔除非人脸的Haar特征值,实现快速人脸识别;根据色彩空间转化实现眼部分割处理,根据PERCLOS值评估驾驶员是否处于疲劳状态并提前予以警示;通过MATLAB仿真软件实现疲劳驾驶检测算法的仿真分析.在多个样本的测试过程中,该方法有效识别出人脸,并能够准确监测驾驶员的疲劳状态. 展开更多
关键词 疲劳驾驶检测 人脸检测 疲劳特征提取 PERCLOS值 viola-Jones
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