Genetic Variation in Rhizome Lotus(Nelumbo nucifera Gaertn.ssp.nucifera) Germplasms from China Assessed by RAPD Markers

To estimate genetic variation in rhizome lotus （Nelumbo nucifera Gaertn. ssp. nucifera） germplasms in China, a total of 94 rhizome lotus germplasms collected from 18 provinces in China were assessed. The RAPD （randomly amplified polymorphic DNA） marker was employed. The selected 17 random primers detected 139 polymorphic alleles out of a total 207 （67.15%）. Nei＇s gene diversity statistics and region differentiation parameters indicated that all germplasms had a relatively high level of genetic diversity with ne = 1.3202, h = 0.1937, I= 0.2982 and the gene flow among all regions was Nrn = 5.5742. The UPGMA dendrogram clustered all 94 germplasms into two clusters： One contained eight commercial cultivars and major landraces, and the other included the wild and some special landraces from five regions, and the PCA analysis exhibited the similar result. Those germplasms from southwestern and eastern China had higher genetic diversity than those from the southern, northern and central China. Predominant proportion of genetic variation （95.61%） was found significant within rather than among （4.39%） regions, as revealed by AMOVA analysis. The data analysis also revealed that the genetic diversity of rhizome lotus germplasms among different regions is positively related to their geographic distances, though it is ambiguous to find the trend from the UPGMA dendrogram and the PCA analysis. A relatively high genetic diversity and gene flow resided in the root lotus germplasms; about 96% of the variation was found within region; accessions from southwest and eastern China have higher genetic diversity than those from the southern, northern and central China.

Genetic Diversity of Lotus(Nelumbo nucifera Gaertn.) Cultivars Revealed by ISSR Analysis

[ Objectives ] This study was conducted to investigate the genetic diversity of 20 lotus （Nelumbo nucifera Gaertn） samples. [ Methods ] On this optimal ISSR amplification system, 16 primers were screened with good polymorphism, and the DNA was used to amplify the 20 plant samples. [ R^ults] The 16 primers produced 225 loci, of which 170 were polymorphic, and the polymorphic loci percentage was up to 75.56%. The genetic similarity coefficients between the 20 vari- eties ranged from 0. 577 8 to 0.951 1, which were calculated by POPGENE32. The 20 varieties by UPMGA analysis could be clustered into 2 groups, the first of which included Baiyangdian red lotus and Donggua lotus, and other varieties was included in the second group. [ Conchmions] ISSR molecular markers could be effectively used in genetic diversity and fingerprint analysis for different lotus varieties.

Genetic diversity of the wild Asian lotus (Nelumbo nucifera) from Northern China

Asian lotus(Nelumbo nucifera Gaertn.)is an aquatic plant with ornamental,cultural,economic,and ecological values.China has abundant germplasm resources of Asian lotus.However,in many areas,the wild Asian lotuses have been destroyed and the germplasms is now facing extinction.In addition,the knowledge of the genetic diversity of the wild Asian lotus in China is poor.To identify and protect the germplasms of Chinese wild Asian lotus,eleven genomic-SSR primers,three EST-SSR primers,and three chloroplast DNA primers were used to investigate the genetic diversity among 69 samples of wild Asian lotus from 25 locations in northern China.The genetic diversity of 27 samples of wild Asian lotus from southern China and other countries,the ancient Asian lotus,Asian lotus cultivars from China,and Asian-American hybrids was also compared.The genetic diversity of the wild Asian lotus from northern China was characterized as medium,and themean values of observed heterozygosity(Ho)and expected heterozygosity(He)were 0.087 and 0.552,respectively.Based on a UPGMA dendrogram and STRUCTURE analysis,the wild Asian lotus samples in northern China were divided into three groups.The wild Asian lotus samples from northern China contained 16 haplotypes.The Nei’s genetic distance between the wild Asian lotus samples from the Songhua River basin and the Liao River basin in northeastern China was relatively small,and these germplasms might be relatively primitive compared to those from other regions.This study provides essential information regarding the genetic diversity of the wild Asian lotus resources in northern China,and provides a basis for further analysis of population-level genetic evolution through high-throughput sequencing.

Analysis of Accumulating Ability of Heavy Metals in Lotus (Nelumbo nucifera) Improved by Ion Implantation

Heavy metals have seriously contaminated soil and water, and done harm to public health. Academician WANG Naiyan proposed that ion-implantation technique should be exploited for environmental bioremediation by mutating and breeding plants or microbes. By implanting N^＋ into Taikonglian No.l, we have selected and bred two lotus cultivars, Jingguang No.1 and Jingguang No.2. The present study aims at analyzing the feasibility that irradiation can be used for remediation of soil and water from heavy metals. Compared with parent Taikonglian No.l, the uptaking and accumulating ability of heavy metals in two mutated cultivars was obviously improved. So ion implantation technique can indeed be used in bioremediation of heavy metals in soil and water, but it is hard to select and breed a cultivar which can remedy the soil and water from all the heavy metals.

Effect of Specific Structure of Lotus Seed Oligosaccharides on the Production of Short-chain Fatty Acids by Bifidobacterium adolescentis

In order to study the structure of lotus （Nelumbo nucifera Gaertn） seed oligosaccharides and their effect on the proliferation ofBifidobacterium adolescentis, we extracted the oligosaccharides from seeds collected from Jianning County, China. We preliminarily characterized the groups, molecular weights, molecular formulae, component monosaccharides and glycosidic bonds using mass spectrometry （MS） and nuclear magnetic resonance （NMR） after isolation and purification. The lotus seed oligosaccharides contained glycosidic bonds Manp-（1→）, Galp-（1→）, α（1→6）-Glup and α（1→6）-Manp; and mannose was the chief component monosaccharide. NMR analyses showed that ~t-glycosidic bonds and pyranoid rings were predominant in the oligosaccharides. The MS analyses showed that lotus seed oligosaccharides consisted of three oligosaccharides of different polymerization degree, with relative molecular weights of 342, 504 and 666 Da, and corresponding molecular formulae C12H22O11, C18H32O16 and C24H42O21. Research on the effect of lotus seed oligosaccharides on the proliferation orB. adolescentis showed that they effectively promoted the production of acetic, propionic and butyric acids by B. adolescentis through fermentation, and their effect was stronger than that of fructo-, xylo- and isomalto-oligosaccharides. Lotus seed oligosaccharides have potential as a new functional probiotic and lotus seeds should be further explored and utilized as a source of oligosaccharides.

Optimization of slow-release fertilizer application improves lotus rhizome quality by affecting the physicochemical properties of starch

To achieve the dual goals of high yield and good quality with low environmental costs,slow-release fertilizer(SRF)has been widely used in lotus cultivation as new type of fertilizer instead of traditional nitrogen fertilizer.However,the optimal amount of SRF and how it would promote lotus rhizome quality remain unclear.This study was designed to investigate the photosynthetic characteristics and the synthesis,accumulation,and physicochemical properties of lotus rhizome starches under six SRF levels(CK,S1,S2,S3,S4,and S5).Compared with CK(0 kg ha^(–1)),the net photosynthetic rate(P_(n))and SPAD values of leaves remained at higher levels under SRF treatment.Further research showed that SRF increased the lotus rhizome yield,the contents of amylose,amylopectin,and total starch,and the number of starch granules.Among the six SRF levels,S3(1035 kg ha^(–1))showed the greatest difference from CK and produced the highest levels.With the increasing SRF levels,the peak,hot and final viscosities decreased at first and then increased,but the setback viscosity and pasting temperature increased.In order to interpret these changes at the molecular level,the activities of key enzymes and relative expression levels of starch accumulation related genes were analyzed.Each of these parameters also increased under SRF treatment,especially under the S3 treatment.The results of this study show that SRF,especially S3(1035 kg ha^(–1)),is a suitable fertilizer option for lotus planting which can improve lotus rhizome quality by affecting starch accumulations related enzymes and genes.These results will be useful for SRF application to high-quality lotus rhizome production with low environmental costs.

Whole genome re-sequencing reveals evolutionary patterns of sacred lotus (Nelumbo nucifera)

Sacred lotus(Nelumbo nucifera or lotus) is an important aquatic plant in horticulture and ecosystems. As a foundation for exploring genomic variation and evolution among different germplasms, we re-sequenced 19 individuals from three cultivated temperate lotus subgroups(rhizome,seed and flower lotus), one wild temperate lotus subgroup(wild lotus), one tropical lotus group(Thai lotus) and an outgroup(Nelumbo lutea). Through genetic diversity and polymorphism analysis by non-missing SNP sites widely distributed in the whole genome, we confirmed that wild and Thai lotus exhibited greater differentiation with a higher genomic diversity compared to cultivated lotus. Rhizome lotus had the lowest genomic diversity and a closer relationship to wild lotus, whereas the genomes of seed and flower lotus were admixed. Genes in energy metabolism process and plant immunity evolved rapidly in lotus, reflecting local adaptation.We established that candidate genes in genomic regions with significant differentiation associated with temperate and tropical lotus divergence always exhibited highly divergent expression pattern. Together, this study comprehensive and credible interpretates important patterns of genetic diversity and relationships, gene evolution, and genomic signature from ecotypic differentiation of sacred lotus.

山东莲藕(Nelumbo nucifera Gaertn.)种质资源的RAPD鉴定和遗传多样性分析

山东莲藕(Nelumbo nucifera Gaertn.)栽培历史悠久,在中国北方具有重要影响。但是,山东莲藕种质资源研究一直没有开展。为收集和保存莲藕种质资源,本研究从山东省8个种植面积较大的地区采集了76份莲藕材料,并利用RAPD分子标记对这些材料进行了遗传相似性分析,共鉴定出38份种质资源。遗传多样性指数分析显示,38份种质资源的Nei's多样性指数(H)平均值为0.26,Shannon信息指数(I)平均值为0.41。研究数据表明,山东莲藕种质资源相对丰富,但要建立高质量的种质资源圃,仍需要加强种质资源的引进。

莲藕膨大过程中碳水化合物变化的初步研究

在莲藕膨大过程中,测定其干物质、淀粉、可溶性总糖、还原糖、可溶性蛋白质等含量,研究碳水化合物的变化规律。结果表明:干物质、淀粉和可溶性蛋白质含量在莲藕膨大过程中均逐渐上升,至膨大后期有一个急增过程;还原糖含量先有所上升,膨大中期迅速下降,至膨大后期维持较稳定水平;可溶性总糖含量从膨大始期至膨大中期平缓上升,至膨大后期则迅速增加。莲藕根状茎的储藏物质主要为淀粉。

钾素营养对莲藕生长和干物质累积的影响

采用大盆试验研究了钾素营养对莲藕生长和干物质累积的影响,结果表明,钾素营养明显增加莲藕立叶数量和立叶面积、提高立叶相对叶绿素值和组织器官含水量、延缓叶片衰老、增强立叶抗逆性,从而促进莲藕生育前期光合产物的累积和健康生长;钾素营养还适当延长莲藕成熟期,促进干物质从叶片转移并贮存到产品中,使莲藕增产20.4%。

莲藕部分种质资源数量性状的聚类分析与育种应用

对 17个不同地区、不同类型的莲藕资源进行了系统聚类分析 ,将莲藕分为野生资源类、地方品种资源类和改良品种类三大类群。品质性状野生资源最优 ,地方品种和改良品种相当 ;农艺性状改良品种最优 ,地方品种居中 。

不同干燥方式对莲藕脆片品质的影响

为明确休闲莲藕脆片的最佳干燥方式,采用热风干燥、真空微波干燥、热风-真空微波干燥、热风-气流膨化干燥、真空微波-气流膨化干燥、热风-真空微波-气流膨化干燥6种不同的干燥方式对莲藕片进行干燥后,对所得脆片的色泽、收缩率、硬度、脆度、VC保留率、多酚保留率以及微观结构等品质指标进行分析。结果表明:热风干燥对莲藕脆片色泽影响不大,但硬度过低,脆度差,VC和多酚损失最为严重;真空微波干燥莲藕脆片VC和多酚保留率高,脆性好,但硬度过高,产品皱缩严重,色差和褐变度高;4种不同联合干燥方式生产的莲藕脆片品质较单一干燥的产品均有所改善,其中,热风-真空微波-气流膨化干燥的莲藕片收缩程度和褐变程度较真空微波干燥显著降低,而VC和多酚保留率较热风干燥显著升高,硬度、脆度均适中,多孔性好。综上所述,热风-真空微波-气流膨化干燥是最适宜加工莲藕休闲脆片的方法。

莲子心脂溶性生物碱的分离、鉴定

为进一步分离并鉴定保健食品莲子心中活性脂溶性生物碱,根据脂溶性成分和酚性生物碱的化学性质,先将莲子心脂溶性成分提取、分离酚性和非酚性二个部位;再运用多种柱色谱技术分别对这二个提取部位进行分离纯化,并对所得化合物的理化性质和光谱数据(UV,IR,MS,~1H NMR、^(13)C NMR及其2D-NMR)进行分析归纳,最终确定它们的化学结构。从莲子心脂溶性部位共获得12个单体化合物,经鉴定其中10个成分为生物碱。酚性部位有6个化合物,分别为:l-薄荷醇(l-menthol,1),甲基莲心碱(neferine,2),亚美罂粟碱(amepavine,3),4'-甲氧基-N-甲基衡州(4'-methoxy-N-methyl coclaurine,4),异莲心碱(isoliensinine,5),莲心碱(liensinine,6);非酚性部位有6个化合物,分别为:谷甾醇(sitosterol,7),荷叶碱(nuciferine,8),前荷叶碱(pronuciferine,9),莲明碱(lysicamine,10),N-甲氧基头花千金藤二酮B(N-methoxycepharadione B,11)和N-甲基紫堇定(N-methylcordaldine,12)。其中1、4、10、11和12则为该植物中首次发现的化合物。

莲藕克隆构型与环境的关系

对莲〔NelumbonuciferaGaertn〕在水田及鱼塘的克隆生长格局进行了研究,调查了三个或三个以上的品种莲的叶片大小、叶柄高度、节间长度、分枝角度、分枝节位、结藕节位等参数。结果表明,莲根茎分枝类型为单轴型,新生的次生根茎交替着水平伸向上级根茎的两侧,分枝角度62.6～98.7°,品种之间存在差异。不同品种莲叶柄高度、叶柄粗度、根状茎节间长度、根状茎节间粗度随着植株生长越来越大,与以前报道并不一致。主枝结藕节位可作为判断莲藕熟性的指标之一。莲克隆构型在不同品种、不同生长环境之间有明显差异。

湖北省莲藕品种演变及栽培利用特点

湖北省是莲藕起源地之一,亦为我国莲藕重要产区。其品种演变历史可划分为传统品种阶段(1980年以前)、新品种选育的起步和奠基阶段(1980～1990年)、传统品种更新和新品种快速推广与持续选育时期(1990年以后)。不仅拥有许多传统品种,而且选育了多个新品种,是我国莲藕新品种的主要选育地区。在莲藕茬口配置、设施栽培、种藕繁殖、采挖以及莲藕产品开发利用等方面具有明显的地方特色。

离子对反相HPLC法测定10个产地莲子心中莲心碱的含量

目的 建立用离子对反相 HPL C法测定莲子心药材中莲心碱含量的方法。方法 选用 ODS色谱柱 ,流动相为甲醇 -水 -冰醋酸 -辛烷磺酸钠 -乙酸钠 (5 5∶ 45∶ 0 .6∶ 10 m mol/ L∶ 5 m mol/ L ) ,检测波长 2 82 nm ,流速为1.0 m L/ min,柱温为 40℃。结果 莲心碱在 0 .0 0 5～ 0 .146 m g/ m L范围内 ,线性关系良好 (r=0 .9999) ;平均回收率为 10 0 .6 % ,RSD为 1.2 1% (n=6 )。结论 该法准确 ,快速 ,灵敏 ,重现性好 。

乳状液膜分离提取荷叶中3种生物碱

建立了用W/O型乳状液膜分离提取荷叶中3种生物碱——N-去甲基荷叶碱、O-去甲基荷叶碱和荷叶碱的方法。通过对迁移时间、表面活性剂Span 80用量、载体D2EHPA浓度、油内比、乳水比和内水相盐酸浓度的优化,获得了高效的液膜体系,为:迁移时间2.5 min,表面活性剂Span 80的质量分数为3.0%,载体D2EHPA的浓度为0.01 mol/L,油内比为10∶6,乳水比为10∶60,内水相盐酸浓度为0.2 mol/L。在优化的实验条件下,对荷叶中3种生物碱N-去甲基荷叶碱、O-去甲基荷叶碱和荷叶碱的萃取率分别达到了95.6%、100%和97.9%,相应的富集因子依次为8.73、8.50和8.04。说明该乳状液膜体系能够很好地分离提取荷叶中的N-去甲基荷叶碱、O-去甲基荷叶碱和荷叶碱。

钾营养对莲藕产量形成和氮磷钾养分累积分配的影响

【目的】研究钾营养对莲藕产量形成及氮磷钾养分积累与分配的影响。【方法】采用盆栽试验,设置不施钾(-K)和施钾(+K)处理进行全生育期试验。【结果】莲藕移栽76d后,+K处理叶片和叶柄干物质累积量明显高于-K处理,并均在97d膨大茎成型后逐渐降低;膨大茎干物质累积速率和累积量在早期为+K处理低于-K处理,97d后+K处理的干物质累积速率明显加快,其累积量于139d明显高于-K处理,160d不同处理膨大茎干物质累积量趋于稳定,+K处理为1204g/株,比-K处理高19.7%。在97—160d产量形成关键期,膨大茎中氮、磷和钾的累积量,+K处理比-K处理分别高32.8%、10.3%和74.2%,其中来自其它器官转移的氮、磷和钾,+K处理比-K处理分别高1.20、0.12和1.26g/株,来自根系直接从土壤中吸收转运的氮、磷和钾,前者比后者高2.16、0.04和5.70g/株。莲藕氮、磷、钾累积总量之比-K处理为1﹕0.14﹕0.90,+K处理为1﹕0.13﹕1.31。【结论】钾营养促进莲藕干物质生产和累积、促进根系对养分的吸收并提高莲藕各器官尤其是叶柄中钾的含量,在生育后期促进干物质和养分从叶片等器官转移并贮存到膨大茎中并最终增产。

荷花SRAP-PCR反应体系的优化与确立

以荷花(Nelumbo nucifera Gaertn)品种‘新红’叶片为材料,采用L16(45)正交试验设计,对SRAP-PCR反应体系中的Mg2+、dNTPs、TaqDNA聚合酶、引物和模板DNA用量5因素进行了优化,并确立了适用于荷花SRAP-PCR的最佳反应体系。结果表明:荷花的SRAP-PCR最佳反应体系为:反应总体积10μL,包含2.0 mmol.L-1 Mg2+、300μmol.L-1 dNTPs、0.5 UTaqDNA聚合酶、4μmol.L-1上下游引物、50 ng DNA及10×PCR Buffer。各因素水平变化对反应体系影响由大到小依次为:TaqDNA聚合酶、Mg2+、引物、dNTPs、DNA。用48个荷花品种对优化的SRAP-PCR反应体系进行验证,均获得了条带清晰、多态性丰富的扩增图谱,证实了该体系的稳定性和适应性。

LC/MS/MS鉴定莲子心生物碱在Caco-2细胞中的代谢产物

目的：应用LC/MS/MS鉴定去甲乌药碱、莲心碱、异莲心碱、荷花碱4种莲子心生物碱在Caco-2细胞中的代谢产物,推测其代谢途径。方法：100μmol/L生物碱作用Caco-2细胞3～12 h后收集并纯化样品,采用LC/MS/MS分析鉴定代谢产物。结果：去甲乌药碱的代谢产物有甲基化去甲乌药碱和去甲乌药碱葡萄糖醛酸苷;莲心碱和异莲心碱的代谢产物分别是去甲基莲心碱和去甲基异莲心碱;荷花碱的主要代谢物为莲心碱、异莲心碱和它们的进一步去甲基产物。结论：LC/MS/MS操作简便,可快速鉴定Caco-2细胞中的莲子心生物碱的代谢产物。莲子心生物碱主要代谢途径有甲基化、去甲基化和葡萄糖醛酸化。