共查询到18条相似文献，搜索用时 234 毫秒
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对兔耳风属杏香兔耳风、红背兔耳风、铁灯兔耳风这3个种的根、茎、叶、叶柄的微观形态特征进行了解剖和比较分析.结果表明:杏香兔耳风和红背兔耳风4种器官微形态结构相似,亲缘关系较近.而铁灯兔耳风在这4种器官的微形态结构方面与上述两个种之间存在着显著差异:铁灯兔耳风根的木质部为二原型,中央无髓,另两个种则为三原型,中央有髓;铁灯兔耳风叶柄维管束为3个,另两个种则为5个;铁灯兔耳风叶片栅栏组织和海绵组织分化不明显,而另两个种则分化明显;铁灯兔耳风茎的维管束数量在13个以上,维管束之间射线细胞较窄,而另两个种的维管束数量在11～13之间,维管束之间射线细胞较宽,可以明显区分出维管束.这说明铁灯兔耳风与杏香兔耳风、红背兔耳风之间的亲缘关系较远. 相似文献
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采用组织离析法和石蜡切片法研究蜡梅营养器官解剖学结构的结果表明:蜡梅芽具有芽鳞;蜡梅具有典型的异面叶,表皮角质层较厚,表皮具有表皮毛,气孔多集中在下表皮,为平行列型;栅栏组织由两层细胞组成,栅栏组织与海绵组织厚度的比值高,主脉维管束呈列状排列,木纤维和韧皮纤维较发达;蜡梅根的初生木质部导管数量多、口径大,髓部为木质部占据;次生根周皮增厚;幼茎木质部含有较多的导管,茎中韧皮纤维和髓部发达;老茎的维管束紧密排列连成环状,茎的每个突起部位都有成团的韧皮纤维;蜡梅解剖结构特点说明腊梅与其山林干燥、寒冷的生长环境相适应,具有耐旱性及抗寒性。 相似文献
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研究八角莲营养器官根、根茎、茎、叶的横切面的组织形态结构。采用石蜡切片法和水合氯醛装片法。结果表明,八角莲根茎中含有特殊的石细胞环;茎中木质部符合双子叶植物茎的构造特征,同时兼有单子叶植物的茎迹维管束存在;叶为等面叶;粉末为淡黄棕色,石细胞极多。 相似文献
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作者对我国东部亚热带地区的双子叶木本植物中的50余科,不同区域,不同海拔的部分(2000余株乔灌木)的叶柄维管束和叶迹进行了研究,初步结果如下:1.属于同目、同科、同属的树种,其叶柄维管束和叶迹有统一的格式(共性)和独自的特点(个性);2.叶柄维管束指示着植物的进化系统,它们是遵循三元进化序列发展的。 相似文献
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The “wood” of palms consists of primary vascular bundles imbedded in a parenchymatous ground tissue. The texture and hardness of a palm stem or petiole depend largely upon the distribution of vascular bundles and the amount of sclerenchyma present. The sieve elements are structurally similar to those in other angiosperms. However, in palms the sieve elements are long-lived, unlike those in most dicotyledons and gymnosperms. Metaxylem tracheary elements vary in their morphology depending on the organ and/or species in which they occur. Scanning electron microscopy observations indicate that the distinction between tracheids and vessels is not sharp but is a matter of degree. The fibers usually have a well developed secondary wall with a characteristically mulilayered appearance. There are indications that the protoplast of these cells continues to lay down secondary walls over a long period. Fibers are commonly associated with silica-containing cells, the stegmata. 相似文献
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利用组织培养培技术对金线莲茎段组培苗进行研究试验。结果表明:以金线莲茎段为外植体,用0.1%升汞溶液消毒10 min效果比较好,杀伤力小,容易获得无菌材料,消毒之前剥开叶柄基部鞘状抱茎消毒效果好;芽增殖培养基用MS+糖30 g·L~(-1)+琼脂粉4.5 g·L~(-1)+马铃薯汁10 g·L~(-1)+激素以6-BA3.0 mg·L~(-1)+NAA0.5 mg·L~(-1)有利于金线莲的增殖与生长;在生根阶段以1/2MS+糖30 g·L~(-1)+琼脂粉4.5 g·L~(-1)+马铃薯汁10 g·L~(-1)+活性炭0.5 g·L~(-1)+NAA1.0mg·L~(-1)效果最理想,生根率达95%,根系发达,叶子展开墨绿色;种植理想的基质为泥炭土∶椰糠∶细沙=5∶3∶2,种植成活率高达97%,幼苗生长旺盛。 相似文献
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Petiveria alliacea is a perennial herb native to the Amazonian region and used in traditional medicine for different purposes, such as diuretic, antispasmodic and anti-inflammatory. The morphoanatomical characterization of the leaf and stem was carried out, in order to contribute to the medicinal plant identification. The plant material was fixed, freehand sectioned and stained either with toluidine blue or astra blue and basic fuchsine. Microchemical tests were also applied. The leaf is simple, alternate and elliptic. The blade exhibits paracytic stomata on the abaxial side, non-glandular trichomes and dorsiventral mesophyll. The midrib is biconvex and the petiole is plain-convex, both traversed by collateral vascular bundles adjoined with sclerenchymatic caps. The stem, in incipient secondary growth, presents epidermis, angular collenchyma, starch sheath and collateral vascular organization. Several prisms of calcium oxalate are seen in the leaf and stem. 相似文献
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以红花烟草为试验材料,研究有机土壤与普通土壤条件下烟草的形态及根系内部的变化情况,结果表明：有机土壤条件下培育出的烟草各项形态指标明显优于普通条件下生长的烟草。对根系做石蜡切片处理后发现,有机土壤条件下生长的烟草细胞体积较大,栅栏细胞排列更加整齐、紧密,但根系没有普通土壤条件下的发达。 相似文献
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Half-sib seed of several eastern white pine (Pinus strobus L.) families was used to examine seed mass effects on laboratory germination, and seedling emergence and growth under moderate
and low light (47 and 13% full sunlight) in a greenhouse. Percent germination and speed of germination under laboratory conditions
were not related to seed mass among half-sib families or multi-family seedlots bulked by seed mass. Percent seedling emergence
in the greenhouse was not related to seed mass, but families with heavier seeds exhibited faster emergence. Both rate and
percent emergence were significantly increased under low light. Family differences in leaf, stem, root, and total seedling
dry mass, primary root length, and the number of first-order-lateral-roots were positively related to seed mass in both light
environments. Low light diminished the absolute biomass increment per unit seed mass, but the proportional change in biomass
with seed mass was similar between light environments. Rate of emergence also influenced seedling size within families, with
earlier emergence increasing seedling dry mass from 7 to 58%, dependent on light environment. Biomass partitioning coefficients
were influenced by light environment but largely independent of seed mass. 相似文献
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定植密度和施肥种类对蕨菜生长及产量的影响 总被引：1，自引：0，他引：1
蕨菜[Ｐｔｅｒｄｉｕｍａｑｕｉｌｉｎｕｍ(Ｌ.)Ｋｕｈｎ]是野生于天然林区的一种蕨科蕨属多年生宿根性草本植物,因其幼嫩茎叶富含多种对人体有益的维生素、胡萝卜素和铁锌等微量元素,自古以来被人们视为山珍采摘食用。近年来,随着人民生活的改善和对外贸易的扩大,蕨菜又成为内销外贸的抢手货,并且需求量不断增加。由此导致了对野生蕨菜连年过量采摘,加之人畜践踏破坏,资源锐减,产量下降,再完全依赖自然生产已越来越不能满足需求。为此,国内外近年开展了有关蕨菜原生地人工驯化栽培工作(齐乐贤,1991;吴会胄等,1994),但蕨菜人工异地栽培的报… 相似文献
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Stem cuttings of Eucalyptus globulus are used within tree improvement programs and for mass deployment. To be successful, cuttings must perform as well or better than seedlings. The root systems of cuttings are fundamentally different from those of seedlings. If these differences influence growth, the differences and their consequences must be identified and the propagation system manipulated to improve performance of the propagules.Cuttings are only a viable alternative to seedlings as planting stock if the method of propagation does not affect their growth and development adversely. Full-sibling cuttings and seedlings of Eucalyptus globulus were compared under controlled environmental conditions to minimise extraneous sources of variation, and to establish whether changes in growth or development were induced by propagation. On three occasions over a period of eight weeks root-collar diameter, shoot height, leaf and stem weight, shoot/root ratios and root system morphology were measured on cuttings and seedlings. Seedlings were taller than cuttings throughout the experiment, but both plant types had similar height growth rates. Diameter growth rates were lower in cuttings than seedlings, and there were differences in both height and diameter growth rates between families. Root system configuration differed between the plant types. Seedlings had strongly gravitropic tap-roots, with two types of primary roots from which secondary roots emerged. Cuttings had no tap roots, and the main structural components of their root systems were adventitious roots formed during propagation. Cuttings did not develop further structural roots during the experiment, whereas seedlings continued to develop primary roots. Individual primary roots of cuttings were longer and had larger mid-point diameters than those of seedlings, but the total length of primary roots was greater in seedlings. Seedlings also had a greater number and total length of secondary roots. Shoot/root ratios, calculated from a range of functional measures, were higher in cuttings than seedlings. 相似文献
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Results from three studies conducted in bare-root nurseries indicate a positive linear relationship between seed spacing and root growth potential of Pinus taeda L. seedlings. However, root growth potential was also correlated with several morphological variables, including seedling weight, root collar diameter, root weight, root volume, foliage weight and stem weight. Because seedlings grown at wider spacings were larger in diameter and biomass, covariate analyses (using either root collar diameter or foliage ovendry weight) were also conducted. These analyses indicate that differences in root growth potential between seed spacings can be accounted for by differences in seedling size. 相似文献