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普通小麦×东方旱麦草属间杂种的产生及无性系的建立 总被引:3,自引:0,他引:3
本研究以普通小麦(TriticumaestivumL.;2n=6x=42,AABBDD)为母本,以东方旱麦草(Eremopyrumorientale(L.)Jaub.etSpach;2n=4x=28)为父本,首次成功地获得了属间远缘杂种F1,其平均结实率为0.08%。利用植物细胞工程技术,对杂种幼胚愈伤组织的诱导、胚性无性系的建立、植株再生、壮苗培养等,最终获得了生长正常的杂种F1植株。同时,通过对杂种幼胚愈伤组织、根尖细胞的细胞学观察,结果表明该杂种为真杂种,即2n=5x=35(预期染色体数)的杂种细胞占主体;另外,因组培过程中发生了染色体数目的变异,故也有少量2n=28-34染色体数的细胞。以上杂种的获得为将旱麦草优异基因向小麦的转移奠定了基础。 相似文献
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在液体培养基条件下对中国产乌毛蕨(Blechnum orientaleL.)配子体发育进行了观察。结果表明:乌毛蕨的孢子为两面体型,两侧对称,极面观为椭圆形,赤道面观为半圆形或豆形,周壁具脊状褶皱;孢子萌发为书带蕨型;原叶体发育为三叉蕨型,成熟原叶体为对称的心脏形。经比较分析,蕨类植物孢子繁殖时采用混合土培养较适宜;液体培养基和混合土在研究蕨类植物配子体发育时同样具有可行性。孢子形态和配子体发育的观察结果表明,乌毛蕨是蕨类植物中较进化的种类;乌毛蕨科与鳞毛蕨科亲缘关系较近。 相似文献
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Tindaria kretensis n. sp., a minute deep-water protobranch, is described from Early Pliocene marls cropping out in the Voutes section, northern Crete Island. This is one of the few fossil records of Tindaria from the Mediterranean area, the first well documented for the Neogene. Tindaria is an almost cosmopolitan deep-water genus, absent from the modern Mediterranean. Its occurrence in the Early Pliocene is in agreement with what is known about the past psychrospheric conditions in the Mediterranean. 相似文献
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In vivo administration experiments using stable (13C) and radio (14C) labeled precursors established that the optically active 8-2' linked lignans, (-)-cis-blechnic, (-)-trans-blechnic and (-)-trans-brainic acids, were directly derived from L-phenylalanine, cinnamate, and p-coumarate but not either from tyrosine or acetate. The radiochemical time course data suggest that the initial coupling product is (-)-cis-blechnic acid, which is then apparently converted into both (-)-trans-blechnic and (-)-trans-brainic acids in vivo. These findings provide additional evidence for vascular plant proteins engendering distinct but specific phenolic radical-radical coupling modes, i.e., for full control over phenylpropanoid coupling in vivo, whether stereoselective or regiospecific. 相似文献
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Questions: On sandy coastal habitats, factors related to substrate and to wind action vary along the sea–inland ecotone, forming a marked directional disturbance and stress gradient. Further, input of propagules of alien plant species associated to touristic exploitation and development is intense. This has contributed to establishment and spread of aliens in coastal systems. Records of alien species in databases of such heterogeneous landscapes remain scarce, posing a challenge for statistical modelling. We address this issue and attempt to shed light on the role of environmental stress/disturbance gradients and propagule pressure on invasibility of plant communities in these typical model systems. Location: Sandy coasts of Lazio (Central Italy). Methods: We proposed an innovative methodology to deal with low prevalence of alien occurrence in a data set and high cost of field‐based sampling by taking advantage, through predictive modelling, of the strong interrelation between vegetation and abiotic features in coastal dunes. We fitted generalized additive models to analyse (1) overall patterns of alien occurrence and spread and (2) specific patterns of the most common alien species recorded. Conclusion: Even in the presence of strong propagule pressure, variation in local abiotic conditions can explain differences in invasibility within a local environment, and intermediate levels of natural disturbance and stress offer the best conditions for spread of alien species. However, in our model system, propagule pressure is actually the main determinant of alien species occurrence and spread. We demonstrated that extending the information of environmental features measured in a subsample of vegetation plots through predictive modelling allows complex questions in invasion biology to be addressed without requiring disproportionate funding and sampling effort. 相似文献
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固相微萃取—气相色谱—质谱联用分析蓼实挥发性成分 总被引:2,自引:0,他引:2
察了萃取样品温度、萃取纤维吸附时间等因素对于固相微萃取蓼实挥发性成分的影响,确定较佳的实验条件为:萃取样品温度60℃,萃取纤维吸附时间60 min,脱附温度250℃,脱附时间5 min。用气相色谱—质谱联用技术测定上述条件所得蓼实挥发性化学成分,并鉴定出其中43种,占总峰面积的76.73%。其中含量较高的物质有:罗汉柏烯 (6.99%),丁香烯 (5.59%),2,5,5,8 a-四甲基-6,7,8,8a 四氢-5H-萘-1-酮(5.52%),α-丁香烯(4.29%),1,2,4a,5,6,8a-六氢-4,7-二甲基-1-异丙基萘(4.04%),环氧石竹烯(3.60%),α-香附酮(3.54%),4,5,5a,6,6a,6b-6氢-4,4,6b-三甲基-2-乙烯基-2H-环丙香豆酮(3.54%),香叶基丙酮(3.48%)。 相似文献
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《L'Anthropologie》2018,122(2):166-182
The rich accumulation of bovid remains found at Buda (Bacău County, eastern Romania) is unique among the Upper Palaeolithic sites in the region. The morphological analysis of postcranial remains, which dominate the assemblage by far, shows they belong to Bison priscus, the steppe bison. The body parts representation is biased towards distal limbs, which also display typical butchery cut marks (resulted from disarticulation or skinning) and bone breakage, suggesting the presence of secondary butchery site where limbs were disarticulated and broken for marrow extraction. The assemblage is dominated by adults, mostly females, and includes few sub-adult individuals and no young juveniles. The large number of bison individuals indicates the found remains are the result of a mass killing event representing at least one hunting episode. Considering the age and sex structure of the population, we estimate that the event can be placed during autumn. 相似文献
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V. Menéndez M. A. Revilla M. A. Fal H. Fernández 《Plant Cell, Tissue and Organ Culture》2009,96(3):245-250
In this study, we report the role of exogenous and endogenous cytokinins on growth and sexual organ development in the fern
Blechnum spicant L. Spore-derived gametophytes (SG) were cultured in full-strength Murashige and Skoog (1962) liquid medium supplemented with (a) 4.44 μMN6-benzyladenine (BAP), (b) a crude extract from mature female gametophytes, and (c) 4.44 μM BAP in combination with the crude
extract from mature gametophytes, respectively. Both BAP and the crude extract delayed the gametophyte development, and this
effect was increased when they were added together. With respect to sexual organ development, BAP inhibited the sexual organ
formation, while the crude extract favored antheridia formation; however, when added together, the percentage of antheridia
decreased. The endogenous level of the cytokinins cis-zeatin (cZ), cis-zeatin-riboside (cZR), dihydrozeatin (DHZ), dihydrozeatin riboside (DHZR), isopentenyl adenine (iP), isopentenyl adenosine
(iPR), isopentenyl-9-glucoside (iP9G), trans-zeatin (tZ), and trans-zeatin riboside (tZR) were analyzed in female and male gametophytes of B. spicant L. The endogenous levels of cytokinins tZ, cZ, DHZ, cZR, iP, and iPR were higher in female gametophytes than in male gametophytes,
with the endogenous iP and iPR content being increased more than 300 and 400 times, respectively. 相似文献
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氮磷钾肥对地道药材建泽泻生长与品质的影响 总被引:2,自引:1,他引:1
通过田间正交试验并结合室内HPLC分析,研究了氮、磷和钾素营养对建泽泻〔Alisma orientale(Sam.)Juzepcz.〕生长和品质的影响。结果表明,施用基肥对建泽泻生长前期的叶片数、株高、叶宽和叶长等农艺性状的影响均大于不施基肥处理;氮、磷和钾施用量对建泽泻产量均无显著影响,当施肥量为纯N 225.0 kg.hm-2、P2O5187.5 kg.hm-2和K2O 225.0 kg.hm-2,总施肥量为637.5 kg.hm-2时,产量最高;氮、磷和钾施用量对建泽泻块茎的粒重均无显著影响;磷的施用量对建泽泻指标性成分23-乙酰泽泻醇B含量有显著影响,而氮和钾均没有显著影响,且影响作用从高至低次序依次为P2O5、N、K2O。 相似文献