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1.
刘建武  刘宁 《植物学报》2001,18(2):149-157
作者概述了蕨类植物生活周期中不同发育阶段的特点,并着重介绍了光、植物生长调节物质、水和温度等因素对蕨类植物配子体发育的影响以及成精子囊素、光、钙离子和其它植物生长调节物质在性器官形成和分化过程中的作用。同时作者对蕨类植物性器官分化的不稳定性进行了探讨、并结合目前蕨类植物性器官分化的遗传学和分子生物学研究的最新进展,说明蕨类植物作为研究系统在植物生物学研究领域中的优势。  相似文献   

2.
植物离体培养中器官发生调控机制的研究进展   总被引:82,自引:0,他引:82  
本文就离体培养的植物组织对生长调节物质的吸收和代谢,外源生长调节物质对内源激素水平的影响,内源激素对细胞脱分化和再分化的调控,生长素和细胞分裂素基因与器官发生的关系,与器官发生有关的基因和特异蛋白等问题的研究进展进行了评述,并对下一步研究提出了自己的看法。  相似文献   

3.
本文就离体培养的植物组织对生长调节物质的吸收和代谢,外源生长调节物质对内源激素水平的影响,内源激素对细胞脱分化和再分化的调控,生长素和细胞分裂素基因与器官发生的关系,与器官发生有关的基因和特异蛋白等问题的研究进展进行了评述,并对下一步研究提出了自己的看法。  相似文献   

4.
植物激素和生长调节物质的研究是植物生理学领域中的重要内容之一,它不仅在植物生理理论研究上占有重要地位,而且对植物生长发育的基本规律和代谢过程的调节控制都有密切关系,同时它在农业上的应用范围和效果,也逐渐扩大和日益明显。但是每一种激素或生长调节物质,在植物生理上都  相似文献   

5.
以细叶小羽藓[Haplocladium microphyllum(Hedw.)Broth.】的配子体为外植体,研究了不同植物生长调节物质对细叶小羽藓愈伤组织诱导及分化的影响。结果表明:在Ms培养基中添加不同的植物生长调节物质对细叶小羽藓配子体增殖影响差异很大,具体表现为2,4一D、KT、IBA和IAA促进细叶小羽藓芽体的诱导及生长,NAA抑制细叶小羽藓芽体的诱导,TDZ阿姨、、及6-BA促进细叶小羽藓的配子体产生愈伤组织;在Ms培养基中添加0.3mg·L-1。6-BA最适合愈伤组织的诱导;在MS掊养基中添加1.0mg·L-1。。IBA最适合愈伤组织的分化。  相似文献   

6.
以驱蚊香草的幼嫩叶片为外植体,在MS培养基上添加各种不同浓度植物生长调节物质进行单因子试验。研究结果表明,不同植物生长调节物质对驱蚊香草的诱导效应不同。2,4-D对驱蚊香草愈伤组织的诱导效果最好;6-BA对芽的诱导显著;NAA对根的分化作用明显。而单独使用NAA,可以从外植体、愈伤组织、根、芽、苗一步完成。  相似文献   

7.
用高压液相色谱及气相色谱法测定几种植物的内源激素   总被引:3,自引:0,他引:3  
吲哚乙酸、赤霉酸、玉米素、玉米素核苷、异戊烯基腺嘌呤、异戊烯基腺嘌呤核苷和脱落酸是重要的天然植物激素,这些物质在植物体内含量很低,但对植物的生长和分化起重要的调节控制作用。为了探讨这些激素的作用机理,这些激素的分析方法一直是植物生理研究中的一个重要课题。植物内源激素的分析,归纳起来有三种方  相似文献   

8.
高等植物中的甾类激素   总被引:1,自引:0,他引:1  
甾类激素(Steroid hormons)一般包括动物性激素、皮质激素和植物油菜素内酯等几类。其中油菜素内酯已在20世纪80年代对其进行了广泛而深入的研究,并确认它能够调节植物的生长发育,是植物重要的生长调节物质。动物中的甾类激素和皮质激素在动物的生长、发育和生殖等方面起着重要作用。早在20世纪30年代,虽然人们就已发现了甾类激素在植物中的存在,但对于它们在高等植物体中功能的研究,一直进展缓慢。近十多年来,随着检测技术的迅猛发展,才使得这一领域的研究取得了长足进展。最初巴特兰德(Butenandt)和杰克比(Jacobi)1933年…  相似文献   

9.
蕨类植物的化感作用及其对生物多样性的影响   总被引:11,自引:0,他引:11  
植物化感作用是植物通过向环境中释放化学物质从而对同种植株和繁殖体或与其他植物之间产生的直接或间接、有益或有害的作用,它影响植物分布、群落形成与演化、作物间作等,与生物多样性保护以及农林和园艺生产实践关系密切,在国际上受到越来越多的关注。但国内这方面的研究起步相对较晚,研究范围有限,对蕨类植物化感作用的报道更少。本文系统介绍了蕨类植物化感作用的研究进展,包括蕨类植物种内的化感作用(即自毒效应)、常见的蕨类植物种间的化感作用(即孢子体对配子体的化感作用和配子体对配子体的化感作用)及蕨类植物对种子植物的化感作用(蕨类植物可通过化感作用与种子植物争夺更多的资源和生长空间)。还介绍了种子植物对蕨类植物的化感作用(主要表现为抑制作用)以及蕨类植物化感作用与动物侵食、微生物侵染的关系,研究发现昆虫侵食能增强或减弱蕨类植物的化感作用,微生物的活动可能增强某些蕨类植物的化感作用。本文从上述不同角度说明蕨类植物化感作用对生物多样性的影响,希望有助于促进我国学者对该领域的深入研究。  相似文献   

10.
众所周知,鞘脂是生物膜结构的重要组成成分,随着鞘脂在动物和酵母中的深入研究发现,鞘脂及其代谢产物是一类很重要的活性分子,它们参与调节细胞的生长、分化、衰老和细胞程序性死亡等许多重要的信号转导过程。鞘脂在植物中的研究最近几年才开始,植物鞘脂的功能还不十分清楚。最近的研究发现,鞘脂及其代谢产物在植物中也起着很重要的信号分子作用。该文详细总结了鞘脂在植物中的结构、代谢途径和主要生物学功能,并结合实验室的工作对植物鞘脂的功能研究进行了展望。  相似文献   

11.
Invasive mammals can fundamentally alter native plant communities, especially on isolated islands where plants evolved without them. The globally invasive feral pig (Sus scrofa) can be particularly destructive to native plant communities. Tree ferns are an important understory component in many forests facilitating the establishment of a variety of species. However, the extent and effects of feral pig damage to tree ferns, and associated impacts on plant community regeneration, are largely unknown. We quantified the effect that feral pig damage has on tree fern growth, survival, and epiphytic woody seedling abundance over 1 year on 438 randomly selected tree ferns of three endemic species (Cibotium chamissoi, Cibotium glaucum, and Cibotium menziesii) in a Hawaiian montane wet forest with high tree fern and feral pig densities. Across all tree fern species, feral pigs damaged 13 % of individuals over 1 year. Compared with undamaged tree ferns, moderately- to heavily-damaged individuals had decreases of 4 to 27 % in trunk length increment and lost tenfold more fronds. Tree fern angle (standing, leaning, prone, or semi-prone) and woody seedling abundance co-varied with feral pig damage. Specifically, damaged tree ferns were more often prone or semi-prone and supported more seedlings, but also had annual mortality up to 34 % higher than undamaged tree ferns. Overall, feral pig damage had substantial negative effects on tree ferns by reducing growth and survival. Given the importance of tree ferns as regeneration sites for a variety of native plants, feral pig damage to tree ferns will likely alter future forest composition and structure. Specifically, feral pig damage to tree ferns reduces potential establishment sites for species that either regenerate preferentially as epiphytes or are currently restricted to epiphytic establishment due to ground rooting by feral pigs.  相似文献   

12.
以7目14科共44种蕨类植物为材料,对它们的花青素、原花青素和总黄酮含量进行检测。结果显示,44种蕨类植物均含有花青素,较为进化的水龙骨目植物的总花青素平均含量明显高于其它蕨类植物。矢车菊素、飞燕草素和天竺葵素是蕨类植物主要的花青素类型,其中乌毛蕨科植物富含矢车菊素,鳞毛蕨科植物富含飞燕草素。本研究中大部分蕨类含有原花青素,水龙骨目植物的原花青素平均含量高于其它蕨类。研究结果表明,蕨类植物中花青素和原花青素等黄酮类化合物的分布与植物科属相关,推测花青素与蕨类植物的生长发育和抗逆过程相关。  相似文献   

13.
蕨类植物性别分化对环境的响应   总被引:3,自引:1,他引:2  
宋莹莹  高晶  戴绍军 《生态学报》2009,29(9):5030-5038
蕨类植物是维管植物中唯一的孢子体和配子体都能独立生活的类群.同型孢子蕨类配子体的性别分化受到激素和环境因子的影响.生理学研究表明,成精子囊素与赤霉素能诱导雄配子体发育,抑制雌配子体发育;脱落酸阻止成精子囊素诱导的精子器形成;乙烯合成前体ACC促进赤霉素诱导的精子器形成,而乙烯合成抑制因子AOA通过抑制细胞分化来抑制精子器形成.光照对不同种类蕨类配子体分化的影响存在差异.糖类能够促进雄配子体形成,并可加速成熟雌配子体向两性分化.钙离子、钴离子和甲硫氨酸等分别参与了蓝光和赤霉素对配子体性别分化的调控过程.培养密度影响配子体生长及性别表达,高密度下雄性和无性配子体居多,而低密度下两性和雌性配子体居多.近年来的突变体表型分析与分子生物学研究表明,成精子囊素通过影响ANI1、HER、TRA、FEM和MAN等基因的表达调控配子体性别分化.综述了蕨类植物性别分化对环境响应的研究进展.  相似文献   

14.
Abstract.
  • 1 The generalization that ferns are under-utilized by phytophagous insects in comparison to angiosperms may be invalid because of biases involving plant growth form, plant range, and unequal sampling efforts.
  • 2 Comparison of nineteen fern species with 652 herb species, the angjosperm growth form most similar to the ferns, indicates no significant difference in the mean number of supported macrolepidopteran species. When the herbs are subdivided into annuals, biennials and perennials, only the annual herbs are significantly different than the ferns.
  • 3 Comparisons of the occurrence distributions for ferns and the herb categories also demonstrate that only the annual herbs support more macrolepidopteran species than the ferns. The same results are obtained when random assemblages of herbs are created that are the same size as the fern assemblage.
  • 4 Both the occurrence distributions and the species–area relationship for the ferns indicate that host records for insects feeding on ferns may be grossly incomplete.
  • 5 The similarity of exploitation of ferns and perennial herbs by the Macro-lepidoptera suggests that other foliage feeding insects may also use ferns at levels equivalent to angiosperms.
  相似文献   

15.
石松类及蕨类植物在高等植物中处于比较特殊的进化与系统发育地位, 同时具有孢子植物(孢子)与种子植物(维管束)的双重特征。附生蕨类植物是蕨类植物中占据独特生境的一个大类群, 其生活史策略及进化历史与其附生生长的森林生态系统紧密相关。大部分附生蕨类植物的克隆生长习性及克隆生活史性状在其生态适应中具有重要作用, 但这方面未引起广泛关注。本文主要综述了中国山地森林中附生蕨类植物的根状茎克隆生长、克隆性与生态适应性、不同克隆生长方式与进化等方面, 并展望了蕨类植物克隆性在森林生态系统过程与功能中的作用, 以及今后如何将蕨类植物生态学研究与气候变化、植被恢复、土地利用变化等全球变化的主流方向进行结合。  相似文献   

16.
Gaxiola A  Burrows LE  Coomes DA 《Oecologia》2008,155(2):325-335
Seedling regeneration on forest floors is often impaired by competition with established plants. In some lowland temperate rain forests, tree fern trunks provide safe sites on which tree species establish, and grow large enough to take root in the ground and persist. Here we explore the competitive and facilitative effects of two tree fern species, Cyathea smithii and Dicksonia squarrosa, on the epiphytic regeneration of tree species in nutrient-rich alluvial forests in New Zealand. The difficulties that seedlings have in establishing on vertical tree fern trunks were indicated by the following observations. First, seedling abundance was greatest on the oldest sections of tree fern trunks, near the base, suggesting that trunks gradually recruited more and more seedlings over time, but many sections of trunk were devoid of seedlings, indicating the difficulty of establishment on a vertical surface. Second, most seedlings were from small-seeded species, presumably because smaller seeds can easily lodge on tree fern trunks. Deer browsing damage was observed on 73% of epiphytic seedlings growing within 2 m of the ground, whereas few seedlings above that height were browsed. This suggests that tree ferns provide refugia from introduced deer, and may slow the decline in population size of deer-preferred species. We reasoned that tree ferns would compete with epiphytic seedlings for light, because below the tree fern canopy photosynthetically active radiation (PAR) was about 1% of above-canopy PAR. Frond removal almost tripled %PAR on the forest floor, leading to a significant increase in the height growth rate (HGR) of seedlings planted on the forest floor, but having no effects on the HGRs of epiphytic seedlings. Our study shows evidence of direct facilitative interactions by tree ferns during seedling establishment in plant communities associated with nutrient-rich soils.  相似文献   

17.
The choice of food plants often assumes critical importance for a herbivore. Although many studies have investigated host‐plant choice behavior, few have examined preferences (vs. growth and survival) at multiple stages of the life cycle, notwithstanding the importance of identifying the critical stage(s) in an animal’s life history. Fern moths Herpetogramma theseusalis (Lepidoptera: Crambidae) provide an excellent opportunity to test host‐plant choice at several stages. Fern moth larvae feed on distantly related ferns, sensitive Onoclea sensibilis and marsh fern Thelypteris palustris, and adults oviposit on both species. We examined newly hatched larvae, overwintered larvae and ovipositing females to test hypotheses predicting when host‐plant choice takes place (overwintering and mobility hypotheses: overwintering stage determines choice of substrate vs. most mobile stage chooses) and the basis for choice (optimal oviposition and enemy‐free space hypotheses: resource producing highest fecundity vs. lowest losses to enemies). We also evaluated the hypothesis that host‐associated fitness trade‐offs explain host specialization. Only ovipositing females, the most mobile stage, exhibited a clear preference (for marsh fern), consistent with the mobility hypothesis. However, their preference for marsh fern fits neither the optimal oviposition hypothesis nor the enemy‐free space hypothesis; although some larvae initially grew faster on marsh fern, adults reared from the two ferns did not differ significantly in mass and experienced marginally lower parasitism on sensitive fern. Thus, we found no host‐associated fitness trade‐offs. Overwintering losses in marsh fern plots exceeded those in sensitive fern, and mixed plots supported the most overwintered larvae. Preference for marsh fern suggests that early success drives host‐plant choice, an advantage that later disappears. Temporal variability may prevent closer fits to the hypotheses, because both ferns provide the moths with acceptable resources throughout their life cycles.  相似文献   

18.
Hay-scented fern (Dennstaedtia punctilobula (Michx.) Moore) is a native forest understory species that behaves as an invasive plant under certain conditions. Previous work has shown that both increased understory light intensity following overstory thinning and removal of competing plants by herbivores can lead to accelerated growth of hay-scented fern, allowing it to develop dense, nearly monospecific understories that inhibit tree seedling regeneration. To study the relationship between these two factors, we sampled 28 forest stands thinned at different times and subjected to different levels of browsing by white-tailed deer (Odocoileus virginianus), and concluded that more than 15 years of intensive browsing following thinning was necessary for ferns to form closed understory canopies with densities of >90 fronds/m2 and canopy heights of 60–80 cm; thinning alone or intensive browsing alone was not sufficient to cause this level of fern invasion. We applied three treatments to dense fern understories to determine the relative importance of the fern canopy and the dense mat of roots, rhizomes, and dead fronds in the inhibition of tree seedling establishment. Results after two years were: (1) complete removal of the organic mat produced a large germination response of woody and herbaceous species; (2) mixing the organic mat into the mineral soil produced an initial germination response but poor seedling survivorship, as the fern canopy regrew to near pretreatment density; (3) repeatedly clipping the ferns for two years without disturbing the organic mat resulted in a lower germination response than the removal treatment, but rapid growth of seedlings.  相似文献   

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