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61.
Bai Jing-shu Zhu Xiao-qing Li Feng-lan Guo Hui-hong Li Zhi-dan College of Biological Sciences Biotechnology Beijing Forestry University Beijing P. R. China North National Forest Plantlet Exemplary Base Beijing P. R. China 《中国林学(英文版)》2005,7(1)
The aim of this study is to follow each development stage of inflorescence in order to understand the biological feature of flowering and the development of male gametophyte in Anthurium andreanum “Arizona" and to try to find the optimum conditions for its pollination. The methods of dissection and paraffin section were adopted to examine the structural characteristics of anthurium’s tiny floret and the development of the microspore. All the florets of the anthurium arrange on the rhachis helically sub- tended by a colorful bract. Each tiny floret has one gynoecium, four tepals and four stamina. The bract and the florets show different colors during the whole blooming period. The ovary is bicarpellary and has two locules, each of which has one anatropous ovule. The placenta is of a central placentation type. The stylar canal cells not only can produce the secretory mucilage but also can release their own cytoplasm caused by their self-disintegration before the pistil reaches its maturity. The wall of the anther is composed of four layers: epidermis, endothecium, middle layer and tapetum. The tapetal cells and the middle layers’ cells degenerated completely dur- ing meiosis of microsporocytes. The pollen grains were 2-celled at the time of anther dehiscence. Early morning, when the inflores- cences stay at their fifth development stage, is the optimum opportunity for pistil to get pollen grains. The pollen-collection should be done at the end of the seventh stage. 相似文献
62.
The aim of this study is to follow each development stage of inflorescence in order to understand the biological feature of flowering and the development of male gametophyte in Anthurium andreanum ““Arizona““ and to try to find the optimum conditions for its pollination. The methods of dissection and paraffin section were adopted to examine the structural characteristics of anthurium‘s tiny floret and the development of the microspore. All the florets of the anthurium arrange on the rhachis helically subtended by a colorful bract. Each tiny floret has one gynoecium, four tepals and four stamina. The bract and the florets show different colors during the whole blooming period. The ovary is bicarpellary and has two locules, each of which has one anatropous ovule. The placenta is of a central placentation type. The stylar canal cells not only can produce the secretory mucilage but also can release their own cytoplasm caused by their self-disintegration before the pistil reaches its maturity. The wall of the anther is composed of four layers: epidermis, endothecium, middle layer and tapetum. The tapetal cells and the middle layers‘ cells degenerated completely during meiosis of microsporocytes. The pollen grains were 2-celled at the time of anther dehiscence. Early morning, when the inflorescences stay at their fiRb development stage, is the optimum opportunity for pistil to get pollen grains. The pollen-collection should be done at the end of the seventh stage. 相似文献
63.
CO2 浓度升高对红掌光合速率与生长发育的影响 总被引:10,自引:1,他引:10
本试验以开顶式塑料薄膜温室为设施, 研究了高CO2 浓度对红掌叶片光合速率、植株生长、光合酶活性和花期的影响。结果表明: 处理90 d时, 对照组〔大气CO2 浓度( 360 ±30) μmol·mol- 1 〕红掌的株高、叶面积、株干样质量、株鲜样质量与处理前相比分别增加了16.4%、36.1%、101.2%和84.2% , 而高CO2 浓度组〔( 1 000 ±100 ) μmol·mol- 1 〕则分别增加了72.9%、65.6%、217.6%和199.1%。高CO2 浓度组的净光合速率比对照增加46.27%, 气孔导度下降, 促进了叶片中可溶性糖和淀粉积累, 叶绿素含量比对照下降, 而对Rubisco活性影响较小, 乙醇酸氧化酶活性则明显下降。高CO2 浓度处理50 d时, 开花率为25%, 处理90 d时已达到80%以上, 而在整个试验期间对照组未见开花。因此, 高浓度CO2 处理提高了红掌叶片的光合速率和碳水化合物的积累, 促进了营养生长, 提前了花期。 相似文献
64.
65.
为了解红掌种质资源重要观赏性状遗传多样性,以91份红掌种质作为试验材料,对17个重要观赏性状进行鉴定,应用相关性分析、主成分分析和聚类分析等方法分析其遗传多样性。结果表明:供试红掌资源各性状的变异系数为16.27%~66.20%,遗传多样性指数为1.8856~2.0886,说明其具有较高的形态多样性,其中右耳心距变异最大,肉穗花序顶端粗变异最小。相关性分析发现,各观赏性状间存在着较为紧密的正向联系,大部分性状间呈显著或极显著正相关。通过主成分分析,确定的3个主要成分,其累计贡献率为82.991%,由决定植株大小、佛焰苞大小及肉穗花序粗度的指标组成,其中前两个特征对红掌种质多样性影响较大。依据植株大小、佛焰苞大小及肉穗花序粗度进行聚类分析,可将91份红掌种质分为6个类群,各类群特征明显,其中第Ⅵ类群多个性状表现独特,值得特别注意。本研究通过分析红掌种质资源重要观赏性状变异情况,了解其遗传多样性,为红掌遗传改良、种质创新和应用提供理论依据。 相似文献
66.
对来自广东省广州市花卉苗圃场红掌上发生的1种细菌性病害进行了病原鉴定。通过对红掌上分离的病原细菌进行形态观察、染色试验、致病性测定、寄主范围、生理生化性状等常规细菌鉴定技术,结合细菌16S rDNA序列分析,鉴定该红掌细菌性叶枯病的病原菌为地毯草黄单胞菌万年青致病变种(Xanthomonas axo-nopodispv.dieffenbachiae)。 相似文献
67.
[目的]优化红掌组培苗的生根技术体系。[方法]以红掌愈伤组织诱导获得的无菌试管苗为外植体,采用4因素4水平L16(45)正交试验,探讨NAA、IBA、蔗糖和活性炭等因素对红掌组培苗生根效果的影响。[结果]在MS基本培养基添加IBA 0.5 mg/L、活性炭0.7 g/L和蔗糖30 g/L(即A1B4C4D4组合)条件下,诱导生根效果较好;生长素IBA诱导生根的效果优于NAA;极值分析表明影响红掌组培苗生根的因素为IBA活性炭NAA蔗糖,4因素对红掌生根均有影响,但未达到显著差异。[结论]红掌生根培养基的最优组合为A3B4C3D4,即添加NAA 0.2 mg/L、IBA 0.5 mg/L、活性炭0.5 g/L和蔗糖30 g/L的MS培养基对红掌组培苗生根最为有利。 相似文献
68.
安祖花叶片的离体培养 总被引:13,自引:0,他引:13
安祖花离体叶片在1/2MS培养基上进行培养,有效地分化出幼芽,分化率达79.0%,平均幼苗数为4.9。最佳植物生长调节剂组合是BA1.0mg·L-1+KT0.1mg·L-1+NAA0.5mg·L-1。叶片刻伤可明显提高愈伤组织形成及芽分化率。继代过程中出现不定根即可移栽,成活率达85%以上。 相似文献
69.
记述了从火鹤花根部分离鉴定的咖啡根腐线虫(Pratylenchuscoffeae)、食菌茎线虫(Ditylenchusmyceliophagus)、锡博尔滑刃线虫(Aphelenchoidescibolensis)、蘑菇滑刃线虫(A.composticola)和燕麦真滑刃线虫(Aphelenchusavenae)等5种植物线虫. 相似文献
70.