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1.
Investigations were made of the growth ofNelumbo nucifera, an aquatic higher plant, in a natural stand in Lake Kasumigaura. A rise of 1.0 m in the water level after a typhoon in August
1986 caused a subsequent decrease in biomass ofN. nucifera from the maximum of 291 g d.w. m−2 in July to a minimum of 75 g d.w. m−2. The biomass recovered thereafter in shallower regions. The underground biomass in October tended to increase toward the
shore. The total leaf area index (LAI) is the sum of LAI of floating leaves and emergent leaves. The maximum total LAI was
1.3 and 2.8 m2 m−2 in 1986 and 1987, respectively. LAI of floating leaves did not exceed 1 m2 m−2. The elongation rates of the petiole of floating and emergent leaves just after unrolling were 2.6 and 3.4 cm day−1, respectively. The sudden rise in water level (25 cm day−1) after the typhoon in August 1986 caused drowning and subsequent decomposition of the mature leaves. Only the young leaves
were able to elongate, allowing their laminae to reach the water surface. The fluctuation in water level, characterized by
the amplitude and duration of flooding and the time of flooding in the life cycle, is an important factor determining the
growth and survival ofN. nucifera in Lake Kasumigaura. 相似文献
2.
Cuticles of several plant species are covered by tubular wax aggregates that are known to consist mainly of (S)-nonacosan-10-ol. The present work addresses the question whether minor wax components may additionally contribute to these tubules. Thin layer chromatography was used to prepare secondary alkanediol fractions from leaf cuticular waxes of Nelumbo nucifera and Thalictrum flavum, containing nonacosane-3,10-diol, nonacosane-4,10-diol, nonacosane-5,10-diol, nonacosane-7,10-diol, nonacosane-9,10-diol and nonacosane-10,13-diol. From organic solutions all these compounds crystallized in tubular shapes. Possible crystal structures of relevant alkanediol isomers are proposed, in analogy to the lattice geometries of comparable aliphatic compounds. The resulting structural model shows that nonacosan-10-ol and various secondary alkanediols may join in metastable mixed crystals. According to the structural model proposed the admixture of alkanediols to nonacosan-10-ol aggregates should enhance the stability of their tubular habit. 相似文献
3.
对子莲(Nelumbo nucifera Gaertn.)新品种‘武植子莲1号’和‘武植子莲2号’与其他12个主栽子莲品种的莲子产量和品质性状进行分析,并通过隶属函数分析法对他们的营养品质性状进行综合评价。结果显示:不同子莲品种的产量和营养品质性状差异显著,同一品种在不同发育时期莲子的可溶性糖和淀粉含量等营养指标差异较大;鲜莲子的可溶性糖含量显著高于成熟莲子,而蛋白质和淀粉含量显著低于成熟莲子。与12个主栽子莲品种相比,‘武植子莲1号’在产量上较为突出,成熟莲子的淀粉含量达52.15%,是生产天然淀粉的优良品种;‘武植子莲2号’鲜莲子的直链淀粉和支链淀粉含量低,可溶性糖含量达23.43%,适合鲜食。隶属函数分析结果表明,‘武植子莲1号’和‘武植子莲2号’的综合营养品质较好,具有很高的应用价值。 相似文献
4.
Mutations of tissue cultured lotus were induced by treating plantlets with either acute -rays at doses of 0, 2, 3, 4, 5 or 6 krad or X-rays at doses of 0, 1, 2, 3, 4 or 5 krad. The 2-krad dose of either - or X-ray treatments resulted in a 50% survival rate. The use of - and X-rays to induce mutation in lotus resulted in 21 altered characteristics. Mutants from 1- and 2-krad of either or X-rays had long secondary roots and numerous adventitious roots. These mutants also exhibited good shoot growth and healthy rhizome development. Most plants treated with 3–5 krad of either - or X-rays exhibited abnormal characteristics including vitrification, chlorosis, deformed petioles and in addition had inhibited growth of lateral buds, secondary roots and rhizomes. All plants treated with 6 krad of -rays died within 4 weeks. Control plants had stoma lengths of 2.56 m and cytological analysis of the root tips confirmed the diploid chromosome number of 16. Two groups of aneuploid cells were achieved using irradiation at doses of 3 and 4 krad of either - or X-ray. Chromosome numbers were 2n=18 and 20 with associated stoma lengths of 3.43 and 4.34 m, respectively. Abnormal stomata (cyclocytic and deformity) were observed in plants treated with 4 krad of -ray. 相似文献
5.
对籽莲红花建莲(Nelumbonuciferacv.Honghuajianlian)和白心湘莲(N.nuciferacv.Baixinxianglian)杂交而成的幼胚的子叶、胚轴及幼胚叶(芽)形成的愈伤组织,施以赖氨酸加苏氨酸胁迫培养30天,从中筛选出抗性愈伤组织并形成再生植株。低浓度的赖氨酸加苏氨酸促进愈伤组织的生长,而高浓度的赖氨酸加苏氨酸则抑制愈伤组织生长,直至具有致死作用,这种致死作用是因为高浓度的赖氨酸加苏氨酸抑制了天冬氨酸合成途径中的天冬氨酸激酶和高丝氨酸脱氢酶造成的,细胞发生变异后对赖氨酸和苏氨酸产生了抗性,即与天冬氨酸合成途径有关的氨基酸增加。抗性愈伤组织与未胁迫的愈伤组织的氨基酸测定表明,在总计17种氨基酸中,抗性愈伤组织有14种氨基酸含量超过原始愈伤组织,1种持平,2种不及原始愈伤组织。再生抗性植株的莲籽氨基酸测定显示,在17种氨基酸中,有12种超过母本红花建莲,15种超过父本白心湘莲。 相似文献
6.
应用SRAP标记对莲藕资源的聚类分析 总被引:24,自引:1,他引:23
利用一种新的分子标记SRAP技术对17个莲藕品种进行了DNA多态性分析。选取7对引物扩增基因组DNA,共获得168条带,其中159条为多态性条带,每对引物平均提供24个标记信息。由UPMGA方法得到的聚类分析结果表明了17个品种间的遗传关系:(1)亚洲莲与美洲莲之间有明显的差异;(2)在亚洲莲内部,藕莲和花莲有明显的遗传分化,在花莲内部亚洲莲与美洲莲的杂交后代和其它花莲品种之间存在明显的差异;(3)SRAP标记是作分子图谱的好标记,但很难区分遗传关系较近的品种。 相似文献
7.
Hong-Li Tian Xiao-Qing Chen Jian-Xiu Wang Jian-Hua Xue Jun Wen Grant Mitchell Shi-Liang Zhou 《Conservation Genetics》2008,9(5):1385-1388
This paper reports the development of microsatellite primers for Nelumbo nucifera Gaerten. By screening genomic libraries enriched with 10 kinds of probes, Seventeen polymorphic loci were isolated and primers
were designed. Polymorphism of these 17 loci was assessed in 24 individuals. All the 17 loci are polymorphic and the number
of alleles ranged from two to seven. Observed heterozygosity and expected heterozygosity ranged from 0.0000 to 0.9176 and
from 0.2837 to 0.7917 respectively. These microsatellite loci should be useful for studying the genetic diversity of N. nucifera. 相似文献
8.
ISSR analysis of genetic diversity in sacred lotus cultivars 总被引:4,自引:0,他引:4
Yunyun Chen Renchao Zhou Xiaodong Lin Keqiang Wu Xuen Qian Shangzhi Huang 《Aquatic Botany》2008,89(3):311-316
In this study, inter-simple sequence repeats (ISSR) markers were applied to assess genetic diversity and genetic relationships of 92 cultivars of sacred lotus (Nelumbo nucifera Gaertn.), one of the most famous flowers in China. Our results showed that sacred lotus exhibited a low level of genetic diversity (percentage of polymorphic bands, PPB = 55.8%), which may result from its asexual mode of reproduction and long-term artificial selection. Clustering analyses indicated that these cultivars could be divided into two clades. Most cultivars of Chinese lotus species origin were included in one clade, and one cultivar of American lotus species origin was nested in the other clade. The hybrid cultivars from hybridization between the two subspecies were interspersed in these two clades. Seven cultivars native to Thailand formed a distinct subclade among the cultivars of Chinese lotus species origin. Genetic differentiation between two subspecies, and between cultivars from Thailand and other cultivars could be attributed to geographic isolation. The monophyly of three cultivars of Sanshui Winter Lotus and their closest relationships to Chinese lotus species origin suggests that they might have a common origin and may consist completely or mainly of genetic material from N. nucifera subsp. nucifera. 相似文献
9.
10.
The microrelief of plant surfaces, mainly caused by epicuticular wax crystalloids, serves different purposes and often causes
effective water repellency. Furthermore, the adhesion of contaminating particles is reduced. Based on experimental data carried
out on microscopically smooth (Fagus sylvatica L., Gnetum gnemon L., Heliconia densiflora Verlot, Magnolia grandiflora L.) and rough water-repellent plants (Brassica oleracea L., Colocasia esculenta (L.) Schott., Mutisia decurrens Cav., Nelumbo nucifera Gaertn.), it is shown here for the first time that the interdependence between surface roughness, reduced particle adhesion
and water repellency is the keystone in the self-cleaning mechanism of many biological surfaces. The plants were artificially
contaminated with various particles and subsequently subjected to artificial rinsing by sprinkler or fog generator. In the
case of water-repellent leaves, the particles were removed completely by water droplets that rolled off the surfaces independent
of their chemical nature or size. The leaves of N. nucifera afford an impressive demonstration of this effect, which is, therefore, called the “Lotus-Effect” and which may be of great
biological and technological importance.
Received: 19 August 1996 / Accepted: 12 November 1996 相似文献