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新疆野苹果(Malus sieversii(Ledeb.) M.Roem.)植物学性状遗传多样性及相关性分析 被引量:30
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作者 闫鹏 韩立群 +6 位作者 梅闯 刁永强 许正 张学超 马凯 艾沙江.买买提 王继勋 《植物遗传资源学报》 CAS CSCD 北大核心 2016年第4期683-689,共7页
为加强野苹果种质资源利用与研究,促进野苹果研究工作,以3年来调查收集的新疆野苹果(赛威士苹果)的129个单株资源为材料,对单果重、果实纵横经、叶片大小等12个数量性状和叶片颜色、叶尖类型等5个质量性状进行遗传多样性及相关性分析... 为加强野苹果种质资源利用与研究,促进野苹果研究工作,以3年来调查收集的新疆野苹果(赛威士苹果)的129个单株资源为材料,对单果重、果实纵横经、叶片大小等12个数量性状和叶片颜色、叶尖类型等5个质量性状进行遗传多样性及相关性分析。分析结果表明:叶片颜色、叶尖类型、叶姿、叶缘、叶面状态5个质量性状分布频率较集中;单果重、果实纵横经、叶柄长、叶片长宽、可溶性固形物、干周、树高均存在较大变异,变异系数幅度为16%~51%。各性状多样性指数也较大,均值为1.9264,叶片长的多样性指数最小为1.7359;果梗长的多样性指数最大为2.0525。新疆野苹果资源拥有丰富的遗传多样性,在于果实相关性状的多样性指数高,且变异幅度大,表明丰富的遗传多样性是新疆野苹果资源的重要特征。 展开更多
关键词 新疆野苹果 遗传多样性 性状分析 相关系数
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Analysis of Volatile Compounds and Identification of Characteristic Aroma Components of <i>Toona sinensis</i>(A. Juss.) Roem. Using GC-MS and GC-O 被引量:14
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作者 Changjin Liu Jie Zhang +5 位作者 Zhongkai Zhou Zetian Hua Hongying Wan Yanhui Xie Zhiwei Wang Li Deng 《Food and Nutrition Sciences》 2013年第3期305-314,共10页
In this study, volatile compounds present in Toona sinensis (A. Juss.) Roem (TS) were investigated and their characteristic aromatic components were identified using Headspace Solid-phase Microextraction (HS-SPME) fol... In this study, volatile compounds present in Toona sinensis (A. Juss.) Roem (TS) were investigated and their characteristic aromatic components were identified using Headspace Solid-phase Microextraction (HS-SPME) followed by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O). The optimum conditions for extracting the volatiles from TS were achieved with the experimental parameters including the use of a 65 μm polydimethylsiloxane/divinyl benzene (PDMS/DVB) fibre, an extraction temperature of 40℃ and an extraction time of 30 min. Under these conditions, 56 volatile compounds were separated and 53 were identified by GC-MS. Among them, 21 sulfide compounds (42.146%) and 27 terpenes(55.984%) were found to be the major components. The sample was analyzed by GC-O and 26 elutes were sniffed and their sensory descriptions evaluated by an odor panelists. Analysis of the data indicated, two compounds cis and trans isomers of 2-Mercapto-3,4-dimethyl-2,3-dihydrothiophene were major contributors to the characteristic aroma of TS. 展开更多
关键词 Toona sinensis (A. Juss.) roem. Volatile Compounds Characteristic AROMA Components HS-SPME GC-MS GC-O
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涝渍胁迫对丝瓜幼苗生长的影响 被引量:12
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作者 朱进 《湖北农业科学》 北大核心 2014年第9期2067-2069,共3页
以荆州地方丝瓜(Luffa cylindrica Roem.)品种为材料,研究了不同时间涝渍胁迫对丝瓜幼苗生长的影响。结果表明,淹水3 d时,丝瓜幼苗的根系分叉数量显著高于对照(P<0.05);淹水6 d时,根鲜重、根系总长度、根系总表面积、根尖数量显著高... 以荆州地方丝瓜(Luffa cylindrica Roem.)品种为材料,研究了不同时间涝渍胁迫对丝瓜幼苗生长的影响。结果表明,淹水3 d时,丝瓜幼苗的根系分叉数量显著高于对照(P<0.05);淹水6 d时,根鲜重、根系总长度、根系总表面积、根尖数量显著高于对照(P<0.05);淹水9 d时,地上部鲜重、株高显著高于对照(P<0.05);淹水12 d时,叶片数、根系总投影面积、根系总体积显著高于对照(P<0.05)。淹水3 d时,根系直径显著低于对照(P<0.05);淹水9 d时,叶绿素含量显著低于对照(P<0.05)。而在淹水12 d内,丙二醛(MDA)含量与对照相比差异不显著。说明丝瓜的耐淹性较强,淹水对丝瓜没有造成伤害,反而对丝瓜的生长有促进作用。 展开更多
关键词 丝瓜(Luffa cylindrica roem ) 涝渍胁迫 叶绿素 丙二醛 根系
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高温胁迫对丝瓜幼苗抗氧化酶活性及基因表达的影响 被引量:11
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作者 刘晓慧 尚静 +3 位作者 朱宗文 张爱冬 查丁石 吴雪霞 《分子植物育种》 CAS CSCD 北大核心 2020年第24期7989-7996,共8页
以丝瓜品种BG-1-1-3-1为试材,利用人工气候室模拟高温环境下,研究了高温(43℃/38℃,HT)和亚高温(38℃/33℃,HST)胁迫及恢复对丝瓜幼苗生长、抗氧化酶活性及基因表达的影响。结果表明:(1) HT和HST胁迫下,丝瓜幼苗生长受到抑制;随胁迫时... 以丝瓜品种BG-1-1-3-1为试材,利用人工气候室模拟高温环境下,研究了高温(43℃/38℃,HT)和亚高温(38℃/33℃,HST)胁迫及恢复对丝瓜幼苗生长、抗氧化酶活性及基因表达的影响。结果表明:(1) HT和HST胁迫下,丝瓜幼苗生长受到抑制;随胁迫时间延长,丝瓜幼叶MDA含量、O2·-产生速率和H2O2含量呈上升趋势;恢复3 d后,MDA含量、O2·-产生速率和H2O2含量均降低。(2)随胁迫时间的延长,SOD、POD和CAT活性、脯氨酸和可溶性蛋白质含量均呈先升高后降低的趋势,SOD、POD活性和脯氨酸含量均在胁迫3 d时达到峰值,CAT活性、可溶性蛋白质含量分别在胁迫1 d、3 d时达到峰值;恢复3 d后,SOD、CAT活性和呈可溶性蛋白质含量上升趋势,POD活性和脯氨酸反之。LcCu/Zn-SOD1、LcCu/Zn-SOD2、LcCu/Zn-SOD3、LcPOD、LcCAT1和LcCAT2基因表达量的趋势和相应酶活性均一致。且与对照(27℃/22℃,CK)相比,SHT处理的以上生理指标的变化幅度均小于HT。以上结果说明,高温胁迫下,丝瓜幼苗通过上调抗氧化酶基因表达,提高酶活性进而应对短时高温或亚高温胁迫伤害,但当胁迫超过1~3 d时,抗氧化基因表达和酶活性均降低,膜脂过氧化程度加重,膜系统受伤越重。 展开更多
关键词 丝瓜(Luffa cylindrica roem.) 高温胁迫 幼苗生长 抗氧化酶活性 基因表达
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Isolation and characterization of the AGAMOUS homologous gene NTAG in Chinese narcissus (Narcissus tazetta var. chinensis Roem) 被引量:7
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作者 Wang Zheng-ke Gao Jian +1 位作者 Li Lu-bin Peng Zhen-hua 《Forestry Studies in China》 CAS 2006年第1期21-26,共6页
Amaryllidaceae, a monocot plant family, consists of many important ornamental bulb flower species. Chinese narcissus (Narcissus tazetta var. chinensis Roem), its flowers developed at high temperatures and bloomed at... Amaryllidaceae, a monocot plant family, consists of many important ornamental bulb flower species. Chinese narcissus (Narcissus tazetta var. chinensis Roem), its flowers developed at high temperatures and bloomed at lower temperatures during the Chinese Spring Festival, is a traditional Chinese flower with high economic and ornamental value. To study its flower development, a full length cDNA containing MADS box domain from narcissus was isolated by a reverse transcription polymerase chain reaction (RT-PCR) with degenerate oligo-nucleotide primers derived from a conserved MADS- and K-box domain sequence. The 5' and the 3' regions of the gene were amplified using the PCR protocol for the rapid amplification of cDNA ends (RACE). The 690 bp open reading frame encodes 230 amino acid residues. A comparison of the deduced amino acid sequence of NTAG with the sequence of other MADS box proteins showed 91.3% amino acid identities with HAG (Hyacinthus orientalis). Sequence analysis and alignment showed significant similarity with other AG homologues. RNA blot analysis indicated that the narcissus NTAG gene was expressed only in reproductive organs, especially in stamens and carpels. These results indicated that the NTAG gene was an AG homologue and that the AG genes appeared to be structurally and functionally conserved between dicots and monocots. 展开更多
关键词 NTAG (Narcissus tazetta var. chinensis roem AGAMOUS) cDNA amplified fragment length polymorphism Chinese narcissus
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七姊妹山保护区红椿种群动态与谱分析 被引量:8
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作者 汪洋 张敏 +5 位作者 陈霞 周火明 操英南 肖创伟 梁国章 李新枝 《湖北农业科学》 2015年第22期5632-5636,共5页
为研究红椿(Toona ciliata Roem)种群动态,将林木径级代表年龄结构,分析了龄级与种群数量动态,编制了静态生命表,绘制并分析了存活曲线、死亡率曲线和种群损失度曲线,对种群进行了谱分析。结果表明,七姊妹山红椿种群衰退动态指数Vpi=32.... 为研究红椿(Toona ciliata Roem)种群动态,将林木径级代表年龄结构,分析了龄级与种群数量动态,编制了静态生命表,绘制并分析了存活曲线、死亡率曲线和种群损失度曲线,对种群进行了谱分析。结果表明,七姊妹山红椿种群衰退动态指数Vpi=32.32%,稳定动态指数Vpi′=4.039%,属于增长型稳定种群,风险敏感度较高。存活曲线接近DeeveyⅡ型,各龄级个体具有大体相等的死亡率。死亡率qx与损失率Kx均在1、4、6级出现高峰,说明不同阶段红椿生理特性、环境筛与人为干扰因素对种群的影响较大。波谱分析基波A1=0.752 8,A3出现明显小周期,表明红椿种群天然更新存在着周期性,且有小周期的多谐波叠加。 展开更多
关键词 红椿(Toona ciliata roem) 种群动态 谱分析 七姊妹山
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香椿叶提取物抗氧化活性研究 被引量:9
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作者 李世俊 胡永金 《安徽农业科学》 CAS 北大核心 2007年第22期6807-6808,6810,共3页
[目的]为了研究香椿叶提取物的抗氧化活性。[方法]用热水、95%乙醇及75%丙酮分别提取香椿叶中的抗氧化物质,比较了3种溶剂的提取物对O2-.、OH.、亚油酸、DPPH自由基的清除作用。[结果]香椿叶提取物对O2-.、OH.、DPPH自由基具有直接清除... [目的]为了研究香椿叶提取物的抗氧化活性。[方法]用热水、95%乙醇及75%丙酮分别提取香椿叶中的抗氧化物质,比较了3种溶剂的提取物对O2-.、OH.、亚油酸、DPPH自由基的清除作用。[结果]香椿叶提取物对O2-.、OH.、DPPH自由基具有直接清除作用,对亚油酸脂质过氧化反应也有抑制作用。随着提取物浓度的增加,其清除、抑制作用也增强,并呈现明显的量效关系。95%乙醇的香椿叶提取物对O2-.、OH.、亚油酸、DPPH4种体系的抗氧化活性显著高于热水及75%丙酮的提取物(P<0.05)。[结论]香椿叶提取物有一定的抗氧化活性,其添加浓度与抗氧化活性呈正相关。95%乙醇提取香椿叶中的抗氧化物质效果较好。 展开更多
关键词 香椿叶 清除自由基 抗氧化作用
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Genetic analysis of fruit shape traits at different maturation stages in sponge gourd 被引量:6
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作者 ZHANG Sheng HU Jin ZHANG Cai-fang GUAN Ya-jing ZHANG Ying 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第5期338-344,共7页
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for ... The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits (fruit length and fruit perimeter) in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage (1-12 d after flowering) for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage (13-60 datter flowering). The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage. 展开更多
关键词 Fruit length Fruit perimeter Genetic effects Genetic variance Luffa cylindrical roem
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三种楝科植物的挥发物成分分析 被引量:4
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作者 卢进 刘志韬 +2 位作者 李莉玲 温秀军 李奕震 《湖北农业科学》 2016年第2期461-464,共4页
为了探究红椿(Toona ciliata Roem.)、毛麻楝[Chukrasia tabularis var.velutina(Wall)King]和非洲桃花心木[Khaya senegalensis(Desr.)A.Juss]3种楝科植物挥发物组分,采用动态顶空采集法利用气相色谱/质谱(GC/MS)联用法分析了这3种植... 为了探究红椿(Toona ciliata Roem.)、毛麻楝[Chukrasia tabularis var.velutina(Wall)King]和非洲桃花心木[Khaya senegalensis(Desr.)A.Juss]3种楝科植物挥发物组分,采用动态顶空采集法利用气相色谱/质谱(GC/MS)联用法分析了这3种植物挥发性有机物(Volatile organic compounds,VOCs)的主要成分。结果表明,3种楝科植物挥发物组分有萜烯类、芳香烃类、醇类、醛类、烷烃类、酮类、酯类、酸类和酚类,且均以萜烯类为主,以(1R)-(+)-α蒎烯为主要成分。红椿释放22种化合物,萜烯类含量占67.41%;毛麻楝释放19种化合物,萜烯类含量占55.96%;非洲桃花心木释放21种化合物,萜烯类含量占81.27%。 展开更多
关键词 植物挥发性有机物(VOCs) 红椿(Toona ciliata roem.) 毛麻楝[Chukrasia tabularis var.velutina(Wall)King] 非洲桃花心木[Khaya senegalensis(Desr.)A.Juss] 气相色谱/质谱(GC/MS)联用
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九宫山红椿种群结构和空间分布格局分析 被引量:6
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作者 张华香 汪洋 +2 位作者 冷艳芝 杨旭 尹茜 《湖北农业科学》 2017年第14期2685-2689,共5页
对九宫山保护区惟一红椿(Toona ciliata Roem.)群落设立2个样地,研究了T1和T2样地种群空间分布格局。通过龄级划分研究种群年龄结构和动态量化分析,以探讨不同样地红椿种群空间结构与分布格局的成因。结果显示,2个样地的种群分布格局在1... 对九宫山保护区惟一红椿(Toona ciliata Roem.)群落设立2个样地,研究了T1和T2样地种群空间分布格局。通过龄级划分研究种群年龄结构和动态量化分析,以探讨不同样地红椿种群空间结构与分布格局的成因。结果显示,2个样地的种群分布格局在16、25、50、100 m^2时,均为泊松分布;取样面积越大,Lloyd平均拥挤度(m*)和丛生指数(I)越大;T2样地的Lloyd平均拥挤度(m*)和丛生指数(I)值均高于T1样地。T1和T2样地Ⅰ龄级数量分别占总量的41.86%和48.18%,Ⅳ、Ⅴ龄级环境筛与竞争作用加强。2个样地种群动态指数变化差异较大,T1样地为10个龄级,V_Ⅳ、V_Ⅴ、V_Ⅵ为波动;T2样地12个龄级,V_Ⅳ、V_Ⅴ、V_Ⅸ、V_Ⅹ为波动。2个样地种群V_(pi1)=40.83%,V′_(pi1)=2.041,V_(pi2)=49.72%,V′_(pi2)=4.144,均属于增长性种群,天然更新较好,但种群老龄化趋势明显。因此,加强森林抚育,人为制造林窗,将更有利于红椿种群的更新和稳定发展。 展开更多
关键词 红椿(Toona ciliata roem.) 种群结构 空间分布格局 九宫山
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红椿天然种群分布格局的检验方法 被引量:3
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作者 汪洋 汪林波 +3 位作者 余春前 张小勇 张琴琴 陈松 《湖北农业科学》 2016年第13期3383-3386,共4页
为研究濒危物种红椿(Toona ciliata Roem.)的种群分布格局,在谷城南河流域对发现的仅有两个红椿种群(T1、T2)以相邻格子法设置5 m×5 m、3 m×3 m的样方,精确到1 m格子。通过χ2验、Cx的t检验、Morisita I_δ的F检验,对种... 为研究濒危物种红椿(Toona ciliata Roem.)的种群分布格局,在谷城南河流域对发现的仅有两个红椿种群(T1、T2)以相邻格子法设置5 m×5 m、3 m×3 m的样方,精确到1 m格子。通过χ2验、Cx的t检验、Morisita I_δ的F检验,对种群分布格局进行判断是否符合泊松分布。结果表明,T1种群在5 m×5 m、3 m×3 m样方尺度下,C_x和I_δ均为泊松分布,5 m×5 m尺度χ2验为集群分布,3 m×3 m尺度为泊松分布;干扰种群T2种群密度较大,3种检验均为集群分布。因此,分布格局满足χ2验的泊松分布,样方设置应注重尺度和数量;df越大,理论值与观测值更可能越接近正态分布,种群分布格局的检验更加真实可信。 展开更多
关键词 红椿(Toona ciliata roem.) 天然种群 分布格局 检验方法
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恩施不同红椿群落α多样性与种群分布格局相关分析 被引量:3
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作者 江雄波 张敏 +2 位作者 汪洋 刘芳芳 陈政 《湖北农业科学》 2016年第15期3923-3928,共6页
为研究恩施地区红椿(Toona ciliata Roem.)群落α多样性与红椿种群空间分布格局的相关性,采用样方法对恩施4个不同红椿天然群落样地进行调查。对群落α多样性指数与种群空间分布格局相关性分析表明,群落草本与灌木层α多样性指数相关性... 为研究恩施地区红椿(Toona ciliata Roem.)群落α多样性与红椿种群空间分布格局的相关性,采用样方法对恩施4个不同红椿天然群落样地进行调查。对群落α多样性指数与种群空间分布格局相关性分析表明,群落草本与灌木层α多样性指数相关性较低;草本与乔木层α多样性指数之间存在较强负相关;灌木与乔木层α多样性表现为显著或极显著正相关。红椿群落群层间α多样性与种群分布格局相关性表明,群落草本层的多样性与红椿种群分布格局间相关性较低;种群分布格局与灌木和乔木α多样性呈高度负相关。研究表明,群层间α多样性存在较为不同的相关性,可能是由于竞争中不平等的资源分配,影响红椿群落物种的演替方向;红椿群落乔灌层的α多样性指数越高,对红椿种群的分布格局影响越大,促使红椿种群分布格局趋于泊松分布。 展开更多
关键词 红椿(Toona ciliata roem.) Α多样性 种群格局 相关分析 恩施
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Dwarfing effects of plant growth regulators on narcissi 被引量:3
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作者 任旭琴 梁宏伟 +1 位作者 陈伯清 季美云 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期339-341,共3页
The effects of four kinds of plant growth regulators with different concentrations on narcissi were studied in 2001. The results showed that the regulators could inhibit the growths of height and leaves of narcissi. O... The effects of four kinds of plant growth regulators with different concentrations on narcissi were studied in 2001. The results showed that the regulators could inhibit the growths of height and leaves of narcissi. Of the four regulators, the dwarfing effects of paclobatrazol (PP333) and uniconazole (S3307) on narcissi were better than those of chlorocholine (CCC) and dimethyl amino-sussinamic acid (B9). All of the regulators did not have significant effect on the root length. Moreover, the time of flowering was later for the narcissi treated with regulators than that of the control to a certain extent, and the range delayed was from 2 days to 19 days. The correlation analysis results showed that there was a significant correlation between the time of flowering and the concentrations of regulators. The ornament value of narcissi was obviously improved by using the regulators. 展开更多
关键词 Narcissus tuzetta var. chinesis roem Plant growth regulators PP333 S3307 B9 CCC
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Distribution Pattern Scale of Natural Toona ciliata Population
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作者 贺立 徐晓婷 《Agricultural Science & Technology》 CAS 2017年第4期700-703,723,共5页
In order to research the population distribution pattern of endangered species Toona ciliata Roem., the sampling quadrats of 5 mx5 m and 3 m×3 m in size, accurate to 1 mxl m, were established in 2 newly-found onl... In order to research the population distribution pattern of endangered species Toona ciliata Roem., the sampling quadrats of 5 mx5 m and 3 m×3 m in size, accurate to 1 mxl m, were established in 2 newly-found only existing T. cili- ata Roem. communities (T1 and T2) with contiguous grid quadrate method, in the Nanhe River valley, Gucheng County. By X2 test, t-test of distribution coefficient Cx method, and F test of Morisita pattern index Iδ whether the distribution patterns of the T. ciliata Roem. populations conformed to Poisson distribution were checked. The results indicated that, population T1 was in Poisson distribution under 5 m×5 m and 3 m×3 m in size by Cx and 16 methods, but in clumped distribution pattern un- der 5 m×5 m in size by the Chi-square test; however, the population was in Pois- son distribution under the dimension of 3 m×3 m. Population T2 under human dis- turbance had higher population density, indicating clumped distribution under 3 above-mentioned tests. If Chi-square test is satisfied, a distribution pattern is in Poisson distribution, and size and quantity of sampling quadrats should be given pri- ority to; and if df is greater, both theoretical values and observed values tend to- wards normal distribution more probably, and the test of distribution pattern, there- fore will be more dependable. 展开更多
关键词 Toona ciliata roem. Natural population Distribution Pattern scale Testing method
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九宫山红椿种群数量动态及预测 被引量:2
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作者 蔡京勇 汪洋 +3 位作者 阮维桢 舒建敏 尹茜 黄芳 《湖北农业科学》 2017年第10期1873-1877,1887,共6页
通过对九宫山惟一红椿(Toona ciliata Roem.)种群进行调查和数据统计分析,绘制了红椿自然种群的龄级结构图,量化分析了种群各龄级间个体数量、变化动态,编制了种群的特定时间生命表,分析了存活曲线、种群生存函数;运用时间序列模型预测... 通过对九宫山惟一红椿(Toona ciliata Roem.)种群进行调查和数据统计分析,绘制了红椿自然种群的龄级结构图,量化分析了种群各龄级间个体数量、变化动态,编制了种群的特定时间生命表,分析了存活曲线、种群生存函数;运用时间序列模型预测红椿种群数量动态。结果表明,(1)Ⅰ龄级存活植株占总存活植株的45.64%,Ⅱ~Ⅳ龄级占28.20%,Ⅴ~Ⅵ龄级占13.33%,Ⅶ~Ⅻ龄级占12.82%;个体数量变化动态指数VⅠ最高,为62.92%,除V_(Ⅳ)和V_Ⅴ2个龄级间波动外,V_(pi)=45.96%,V_(pi′)=3.83%>0。(2)种群存活曲线:N_x=8.448 e^(-0.09x),R^2=0.956,符合DeeveyⅡ型存活曲线,说明种群在生活史各个阶段具有较为稳定的死亡率。(3)生存率函数S(i)单调下降,积累死亡率F_((i))呈单调上升,两者下降和上升的幅度前5个龄级高于后期,F_((i))到Ⅵ龄级达0.881。死亡密度函数f_((ti))随龄级逐渐下降,到Ⅷ龄级后稳定在0.003。危险率函数λ_((ti))出现Ⅴ、Ⅶ、Ⅺ龄级的3个峰值,均为0.250,龄级结构和动态分析的趋势一致。(4)对Ⅱ、Ⅳ、Ⅵ、Ⅷ龄级动态预测表明,种群各龄级个体数量呈增加-下降-平稳变化,种群趋于老龄化。总之,九宫山红椿种群受特定环境影响,改善了红椿林下幼苗在生长过程中的光照条件,光照环境筛和竞争成为中间龄级植株的抑制条件,因此该种群为增长型种群,但趋于老龄化。在管理上应针对不同阶段种群生长发育特征,采取适当措施,使种群健康发展。 展开更多
关键词 红椿(Toona ciliata roem.) 种群结构 数量动态 预测 九宫山
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Effects of Relative Soil Water Content on Antioxidant Enzyme System in Malus sieversii(Lebed.) Roem 被引量:1
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作者 徐佳宁 刘钢 王文军 《Agricultural Science & Technology》 CAS 2016年第6期1281-1284,共4页
By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechan... By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechanism of M. sieversii to changes of relative soil water content. According to the results, with the decrease of relative soil water content, MDA content in M. sieversii leaves increased by mem- brane lipid peroxidation. Cells resist water stress-induced membrane lipid peroxidation and clear the increased reactive oxygen species by improving soluble protein content and SOD, POD, CAT and APX activities. However, various enzymes were involved in the response to water stress under different moisture conditions. In addition, the results indicated that M. sieversii had a good adaptability to higher relative soil water contents. 展开更多
关键词 Malus sieversii (Lebed.) roem. Relative soil water content Membrane lipid peroxidation Antioxidant enzyme system
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Study on the relationship between Toona sinensis Roem stand productivity and site conditions in Sichuan Basin 被引量:1
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作者 PU Ya-yun CAO Xia 《Ecological Economy》 2010年第4期387-394,共8页
According to the relationship between Toona sinensis Roem stand volume,productivity and forest age,site conditions,stand density and other factors,through selecting 8 representative cities or counties,using standard i... According to the relationship between Toona sinensis Roem stand volume,productivity and forest age,site conditions,stand density and other factors,through selecting 8 representative cities or counties,using standard investigation and stem analysis method,this paper makes relatively systematic research about the Toona sinensis Roem plantation accumulation,productivity,and the relationship between them and site conditions.Through comparative analysis indicators of multiple site conditions,this paper expects to give a more comprehensive picture about the source of accumulation and productivity difference. 展开更多
关键词 Toona sinensis roem PRODUCTIVITY Site conditions Forest management
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Analysis of Genetic Differences between Luffa acutangula(L.) Roxb. and Luffa cylindrica(L.)Roem. by ISSR Markers 被引量:1
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作者 宋波 陈龙正 +2 位作者 徐海 郑涛 费月跃 《Agricultural Science & Technology》 CAS 2015年第11期2437-2440,共4页
The genetic differences among Luffa acutangula (L.) Roxb., Luffa cylindnca (L.) Roem. and their F1 hybrid and F2 population were analyzed by ISSR technolo- gy. The results showed that the genomic DNA of test mater... The genetic differences among Luffa acutangula (L.) Roxb., Luffa cylindnca (L.) Roem. and their F1 hybrid and F2 population were analyzed by ISSR technolo- gy. The results showed that the genomic DNA of test materials showed a high diversity; the genetic similarity coefficient between both parents was only 0.395; the bands of F1 hybrid mainly consisted of both parents'; neither FI nor F2 was inherit- ed singly from male or female parent; there was greater genetic variation among F2 population. 展开更多
关键词 Luffa acutangula (L.) Roxb. Luffa cylinddca (L.) roem. Interspecific hybrid ISSR
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中国水仙(Narcissus tazetta L.var.Chinesis Roem)开花生理研究——Ⅰ.中国水仙的生物学特性及花芽分化的规律
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作者 李文仪 孙景欣 傅家瑞 《中山大学学报(自然科学版)》 CAS 1985年第1期134-136,共3页
中国水仙是多花水仙,具有较高的观赏价值,是我国传统出口珍贵花卉,在我国主要分布于漳州、崇明等地区.近年来,广东潮汕、广州郊区等地引种漳州水仙时均出现不同程度的退化现象,表现为鳞茎小、重量轻、花序数和总小花数均明显减少.针对... 中国水仙是多花水仙,具有较高的观赏价值,是我国传统出口珍贵花卉,在我国主要分布于漳州、崇明等地区.近年来,广东潮汕、广州郊区等地引种漳州水仙时均出现不同程度的退化现象,表现为鳞茎小、重量轻、花序数和总小花数均明显减少.针对这种情况,我们从1982年以来对中国水仙的生物学特性、生长发育。 展开更多
关键词 中国水仙 鳞茎 广州 小花 地下茎 广东 Narcissus tazetta L.var.Chinesis roem 花芽分化 生物学特性
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Embryological Studies on Narcissus tazetta var.chinensis
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作者 Ge Lili Wu Jian +2 位作者 Chen Linjiao Wang Rui Tian Huiqiao 《Frontiers in Biology》 CSCD 2006年第1期18-22,共5页
Chinese narcissus(Narcissus tazetta var.chinensis Roem)blooms but has no seeds.Embryological studies on the species were conducted to discover the causes of its sterility.Its anther wall is composed of four layers of ... Chinese narcissus(Narcissus tazetta var.chinensis Roem)blooms but has no seeds.Embryological studies on the species were conducted to discover the causes of its sterility.Its anther wall is composed of four layers of cells,and its tapetum is of the secretory type.The cytokinesis of microspore mother cells is of the successive type,and the tetrad is tetrahedral.During meiosis of microspore mother cells,some chromosomes lagged,and several micronuclei were found in tetrads.Only 27.7%of the pollen grains contained full cytoplasm,and 1.3%of them germinated in culture medium.No pollen grain,however,could germinate on the stigma.The ovary is trilocular with axile placenta,and the ovules are bitegmic,tenuinucellate,and anatropous.Its embryo sac is of the polygonum type.Most embryo sacs degenerated,and only about 4.5%of the ovules contained a normal embryo sac with an egg cell,two synergids,three antipodal,and a central cell containing two polar nuclei.One reason for the sterility of Chinese narcissus is the abnormality of microsporogenesis and megasporogenesis,in which only a few functional pollen grains and embryo sacs are produced.The other reason is that the pollen grains cannot germinate on the stigma. 展开更多
关键词 EMBRYOLOGY MEGASPOROGENESIS MICROSPOROGENESIS Narcissus tazetta var.chinensis roem
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