蕨类植物

The experiments in the fields suggested that both glyphosate and paraquat could prevent the growth of Pteridophyta, Dryopteris erythrosora 0. Ktze. and Osmunda claytoniana L., effectively.

以红盖鳞毛蕨和绒紫萁为指示植物进行田间试验，结果表明百草枯和草甘膦对这些蕨类植物都可以起到很好的防除作用，但反应时间和表现症状有差异。

The results will have great significance for categorizing the spore types, palynology and systematics of ferns.

研究结果对蕨类植物孢子类型划分、蕨类的分类和系统演化具有重要的科学意义。

Whisk ferns; comprising the family Psilotaceae or Psilotatae: vascular plants with no roots, partial if any leaf differentiation, and rudimentary spore sacs.

蕨类植物；由松叶蕨科或裸蕨纲组成；无根脉管植物，叶仅部分分化或缺乏，孢子囊发育较差。

Betula alnoides forests, grassy slopes, loose peaty soil with ferns, rocky moist places along streams, crevices of cliffs;

Betula alnoides森林，草坡，有蕨类植物松散的泥炭的土壤，岩石的潮湿的地方沿着溪，悬崖的裂缝的；1600-2600米。

Any of various vascular plants , including seed plants and ferns , having a conducting system of xylem and phloem .

导管植物任何种类的管植物，包括种子植物和蕨类植物，具有和韧皮导管系统

Recently polypod ferns have been demonstrated to undergo diversifications in the Cretaceous after the rise of angiosperms. To further test this proposal, an adaptive evolutionary analysis was performed on the rbeL gene sequences of Polypodiaceous ferns under models allowing w (nonsynonymous/synonymous rate ratio) to vary among sites.

为验证蕨类植物在白垩纪适应被子植物兴起而发生分化的观点，本研究以水龙骨科附生蕨类为对象，利用位点间可变ω（非同义替换率d和同义替换率d的比值）模型对其rbcL基因的适应性进化进行分析。

The spore germination and gametophyte development of 21 ferns are studied. It indicates that :① the development period of prothallium and young sporophyte of the same species is different due to seeding time of spores;② the optimal temperatures of spores germination and gametophyte development of 21 ferns are about 15 -24 ℃;③ the rate of spore germination of rare ferns is much lower than the ferns which occur large populations in nature;④ the treatment with GA 3 can accelerate the germination of the spores;⑤ the prothallium changes from large to small, green to yellow when young sporophyte comes out. The prothalliums of all 21 ferns die away after the appear of the 3rd leaf of sporophytes;⑥ shapes of the 1st and 2nd leaves of the young sporophyte are different from those emerged later;⑦ spores cultured in dark can not germinate;⑧ a prothallium can develop only one young sporophyte though it has many archegoniums, and the spore propagation with leaf mould substrate is an economical method.

摘 要：以腐叶土为培养基质，对 21 种蕨类植物进行了孢子萌发和原叶体发育的研究，结果表明：①不同时期播种的同种蕨类的孢子，发育出原叶体和幼孢子体所历经的时间长短不同；②孢子萌发和配子体生长发育的适宜温度约为 15 ～ 24 ℃；③稀有蕨类的孢子萌发率低，而在野外能形成较大种群的蕨类的孢子萌发率高；④用 GA 3 处理孢子可以促进萌发；⑤当原叶体上长出幼孢子体时，原叶体由大变小，由绿变黄， 21 种蕨类的原叶体都在幼孢子体上长出第 3 片叶时消失；⑥幼孢子体上长出的第 1 、 2 片叶在形态上与以后长出的叶不同；⑦孢子萌发需要光；⑧ 1 片原叶体尽管有多个颈卵器，但仅发育出 1 株幼孢子体；⑨利用腐叶土进行蕨类孢子繁殖是一种经济实用的繁殖方法。

The PROTHALLUS of Lycophyta, Sphenophyta, and Filicinophyta, which may be a green structure on the soil surface or a subterranean mycorrhizal structure, is the gametophyta.

石松门、楔叶门、真蕨门的原叶体是位于地表的绿色结构或是位于地下的菌根结构，这些结构便是蕨类植物的配子体。

The fern spore, the original cell of the gametophyte, carries out asymmetrical mitosis to produce a large cell and a small cell. The small cell geminates to a rhizoid by tip growth, and the large cell further divides and develops to become a prothallus.

蕨类植物孢子作为配子体的原始细胞，通过不对称的有丝分裂产生一大一小两个细胞，小细胞萌发出极性生长的假根，大细胞继续分裂发育为原叶体。

Pteridophyte resources in this area are of great utilization value.

保护区内这些蕨类植物资源具有重要的利用价值。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。