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兰花蕉花的形态解剖学 总被引:1,自引:1,他引:1
兰花蕉(Orchidantha chinensis)的子房室顶部闭合后向上延长成延长部,实心,但有花柱沟和隔膜蜜腺管通过,隔膜蜜腺管,可分为中央蜜腺管和三条侧蜜腺管;中央蜜腺管位于三个心皮连接处,自子房室区下部产生,向上于延长部的部顶端终止;三条侧管分别位于两个心皮连接处,于子房室区近中部产生,开口于花柱基部。兰花蕉子房室区与延长部均具6枚雄蕊的维管束系统,即3枚心皮背束的伴束与3枚隔膜束,近轴面1枚事膜向上进入唇瓣的维管束系统,位于唇瓣的中央,致使兰花蕉仅具5枚功能雄蕊,唇瓣具双重结构,本文还讨论了兰花蕉科的系统发育位置。 相似文献
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Khramtsova E. V. Kiseleva I. S. Lyubomudrova E. A. Malkova N. V. 《Russian Journal of Plant Physiology》2003,50(1):19-27
Comparative analysis of the indices of plant growth and mesostructure of the photosynthetic apparatus was carried out with ten wheat (Triticum L.) species of various origins. Wheat alloploid forms (tetra- and hexaploids with the chromosome numbers of 28 and 42) exceeded the diploid forms (the chromosome number of 14) 2.3–2.4-fold by their absolute growth rate (AGR). As a result, the alloploid species developed a larger assimilation area; this change involved the internal reorganization of leaf phototrophic tissues and an increase in the cumulative internal assimilation area. In addition, the alloploid species manifested a higher correlation between the surface areas of cell and chloroplast membranes caused by a decrease in the cell number per the unit leaf area, a relative increase of the number of composite multifaveolate cells, a considerable expansion (in volume and surface area) of mesophyll cells, and an increase in chloroplast size and numbers. The decreased ratio between the characteristics of the cell membrane and chloroplast envelope presumes that CO2 diffusion via cell and chloroplast membranes in the leaves was better balanced in the alloploid wheat species than in the diploid forms. All wheat species did not notably differ in their plastid–cytoplasm ratio (cell volume corresponding to one chloroplast and cell surface area per one chloroplast) and the ratio of surface area of cells to cell volume. The discriminant analysis revealed the indices of leaf growth and mesophyll structure instrumental in distinguishing between the diploid and alloploid species: leaf area, AGR, and cell size and number. The change in the latter indices optimized the structure of leaf phototrophic tissues in tetraploid and hexaploid species; as a result, the internal assimilation area was expanded and, consequently, leaf CO2 conductance was increased. 相似文献
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利用石蜡切片和显微解剖方法对芸香科山小橘属(Glycosmis)国产9个种类11份材料的花部特征进行解剖学研究.结果表明,国产山小橘属植物雄蕊花药顶端具有突尖附属体和油腺2种类型,大部分种类的花药背部具有1至数枚油腺,但山橘树(G.cochinchinensis)的花药具有稀疏长毛;雌蕊的子房柄按其增大程度分为近球形、增大垫状和伸长形3类,子房的形状有近球形和稍增大柱形,子房外壁有光滑、具圆形凸起腺点及具不规则瘤状凸起3种类型,子房室的数目有5室和4(或3)室2种类型,花柱形状分为圆柱状和渐狭柱状,柱头特征分为稍增粗和不明显两类;大部分种类花柱为宿存,仅锈毛山小橘(G.esquirolii)的花柱在果实发育时脱落.山小橘属的花部特征在种间具有较大的差异,可以作为属下类群划分的主要依据之一,具有重要的系统学意义. 相似文献
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对21个代表种果实形态与解剖特征观察发现:(1)中国柴胡属(Bupleurum L.)果实以芹亚科(Apioideae)原始的两侧压扁型为主,在外形上可分为圆柱形、矩圆形和卵形3类;(2)在柴胡属中果皮细胞内没有发现广泛存在于芹亚科基部类群变豆菜亚科(Saniculoideae)和天胡荽亚科(Hydrocotyloideae)的晶体后含物;(3)从果实的横切面看,可将柴胡属划分为棱槽单油管型和棱槽多油管型两大类。结合前人对伞形科其它类群果实形态解剖特征的研究及近年来分子系统学的证据,认为:(1)中国柴胡属植物的多油管类型为本属较进化类群;(2)柴胡属可能是芹亚科中连接基部类群与其它类群的过渡环节或进化旁支;(3)果实形态与解剖特征可作为探讨国产柴胡属种内和种间关系的辅助性状,并给出了分种检索表。 相似文献
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紫花含笑(♀)与灰岩含笑(♂)及其杂种F1代叶表皮微形态和叶结构的比较观察 总被引:1,自引:1,他引:1
通过比较观察紫花含笑(♀)和灰岩含笑(♂)及其杂种F1代叶表皮微形态和叶结构发现,紫花含笑和灰岩含笑在叶表皮微形态及叶解剖结构方面有很大差异。杂种F1代个体间在叶表皮微形态及叶解剖结构方面变异很大,为连续的数量遗传;其中57.7%以上的杂种F1代气孔密度高于父母本。杂种F1代矮化型植株叶片气孔密度较小,推测其抗寒性较强,可以通过进一步杂交改良,获得矮化型的盆栽含笑新品种。观察结果可为深入探讨含笑属种间杂种F1代的遗传变异,并从这些杂种F1代中选育观赏新品种积累科学资料。 相似文献
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猕猴桃叶片耐热性指标研究 总被引:12,自引:1,他引:12
选择中华猕猴桃与美味猕猴桃共7个品种。对耐热性的形态与生理生化指标进行了探讨,结果表明:与耐热性较弱的品种相比,耐热性较强的品种有较大的叶片厚度、栅栏组织厚度,栅栏组织/海绵组织比例及较高的气孔密度,通过离体叶片温浴处理后细胞膜透性的变化拟合出的拐点温度高低可以鉴别品种耐热性的强弱,耐热性较强的品种在热胁迫下叶片游离脯氨酸累积率高于耐热性较弱的品种;品种耐热性与过氧化物酶活性之间无一致规律。 相似文献
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通过比较观察紫花含笑(♀)和灰岩含笑(♂)及其杂种F1代叶表皮微形态和叶结构发现,紫花含笑和灰岩含笑在叶表皮微形态及叶解剖结构方面有很大差异。杂种F1代个体间在叶表皮微形态及叶解剖结构方面变异很大,为连续的数量遗传;其中57.7%以上的杂种F1代气孔密度高于父母本。杂种F1代矮化型植株叶片气孔密度较小,推测其抗寒性较强,可以通过进一步杂交改良,获得矮化型的盆栽含笑新品种。观察结果可为深入探讨含笑属种间杂种F1代的遗传变异,并从这些杂种F1代中选育观赏新品种积累科学资料。 相似文献
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M. J. Mason 《Journal of Zoology》2001,255(4):467-486
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古新世晚期裂齿类———丁氏豫裂兽 (新属、新种 ) (Yuesthonyxtingaegen .etsp .nov.)的发现表明了裂齿目在亚洲古新世已相当分化 ,在臼齿形态上有与北美始新世Esthonyx相近的小尖兽 (Meiostylogon)和中间兽 (Interogale) ,也有与北美Megalesthonyx接近的豫裂兽等。根据豫裂兽、Megalesthonyx、和亚洲的Adapidium的上臼齿都具有明显的中附尖等特征可与其他裂齿类相区别 ,新建了豫裂兽科 (YuesthoncidaeFam .nov.)。 相似文献
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Secretory tissues in vascular plants 总被引:15,自引:3,他引:15
ABRAHAM FAHN 《The New phytologist》1988,108(3):229-257
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中国东北古新世乌云植物群:榆科叉脉榆 总被引:1,自引:0,他引:1
根据叶结构特征。将黑龙江省古新世乌云植物群中的榆科叶化石确定为叉脉榆(Umus furcinervis(Borsuk)Ablaev)。叶化石二级脉达缘且在叶缘区分叉,三级脉及顶,叶缘锯齿两侧边凸出。重新研究了前人鉴定为小叶普拉榆(Planera cf.microphylla auct.non Newberry)和乌云珍珠梅(Sorbaria wuyungensis Tao et Xiong)的叶化石并将其归入叉脉榆。 相似文献
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根据叶结构特征,将黑龙江省古新世乌云植物群中的榆科叶化石确定为叉脉榆(Ulmus furcinervis (Borsuk) Ablaev),叶化石二级脉达缘且在叶缘区分叉、三级脉及顶、叶缘锯齿两侧边凸出.重新研究了前人鉴定为小叶普拉榆(Planera cf. microphylla auct. non Newberry)和乌云珍珠梅(Sorbaria wuyungensis Tao et Xiong)的叶化石并将其归入叉脉榆. 相似文献
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描述并厘定了黑龙江省嘉荫县古新世乌云植物群中的广义山茱萸科绝灭类型镘形美中果 (Amersiniaobtrul lataManchester,CraneetGolovneva)和假古老白令叶 (Beringiaphyllumpseudoantiquum (Golovneva)Manchester,CraneetGolovneva)。将前人鉴定为昆栏树属 (未定种 ) (Trochodendronsp .)的果序化石归入镘形美中果 ;将前人确定为鲜艳杨 (Populuscarneosa)、假原始叶南蛇藤 (Celastrophyllumsubprotophyllum)、古老荚 (Viburnumantiquum)、粗糙荚 (V .asperum)、疏齿荚叶 (Viburniphyllumfinale)、乌云原始叶 (Potophyllumwuyunense)、海丹原始叶 (近似种 ) (P .cf.hay denii)、卵圆原始叶 (P .ovatifolium)和不规则克里木 (Credneriainordinata)等归入假古老白令叶 相似文献
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Fossil seeds and seedlings of a Metasequoia-like taxodiaceous conifer occur in Paleocene deposits at the Munce's Hill and Gao Mine localities of central Alberta, Canada. Compression/impression specimens are preserved in upright growth positions among seedlings of the cercidiphyllaceous dicot Joffrea speirsii Crane & Stockey. There are a large number of seeds, a few of which were buried while germinating and show a radicle or short primary root. More than 500 Metasequoia-like seedlings have been identified that have two linear cotyledons with parallel margins and rounded tips. Three specimens have been found that display three cotyledons. Slightly older seedlings show decussate pairs of leaves attached to the stem distal to the cotyledons. Still older seedlings have axillary branches that show varying sizes and numbers of opposite leaves arranged in a single plane distal to the opposite pairs. These specimens reveal that both Joffrea and this extinct taxodiaceous conifer were early colonizers of North American floodplain communities at the beginning of the Tertiary. 相似文献
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Hou Lianhai 《古脊椎动物学报》1994,(1)
redspecimenrepersentsanewgenusandspecies.Wanshuinaliigen.etsp.nov.SpecimenShaftofarighthumerus,andthedistalendofaIefttibiotarsusanda1efttarsometatarsus,Vlo529.DistributionQianshan,AnhuiProvince;Paleocene,DoumuFormation.DiagnosisSizesma1l-medium,humeruss1enderandlong,mediancrestventraleelongated,tibiotarsuscompressedanteroposteriorly,externalcondy1eroundinlateraIview,grooveforperoneusprofundusdeepandlong;internalcondylelongerthanex-ternalcondyle,adepressionwelldeve1opedin1owerborder0finter… 相似文献