小车前(Plantago minuta Pall.)种子表面粘液物质的吸水特性及其对种子在干旱环境中萌发的影响

为了理解荒漠短命植物小车前(Plantago minuta Pall.)种子表面的粘液物质对种子在干旱环境中萌发的作用,在室内控制条件下研究了粘液物质的吸水保水特性、剥离粘液物质的种子(无粘液种子)和保留粘液物质的种子(粘液种子)在-1.15^-0.15MPa不同渗透胁迫条件下的萌发状况。结果表明:(1)小车前种子表面的粘液物质干重占粘液种子干重的5.6%;在去离子水中,粘液物质可以吸收相当于其自身干重217.1倍的水分;粘液物质的存在使得小车前种子的吸水倍数由2倍增加至14倍,从而保证为种子萌发提供充足的水分;(2)干燥的粘液种子吸水2h后即达到饱和,而吸水饱和后的粘液种子在室温下晾置,经过48h后又干燥失水恢复至原重;(3)在去离子水中或低渗透胁迫(-0.33^-0.15MPa)条件下,粘液物质吸水作用能促进小车前种子萌发,粘液种子3d的发芽势和10d的总萌发率均显著高于无粘液种子;在高渗透胁迫(-1.15^-0.73MPa)条件下,粘液种子3d的发芽势显著低于无粘液种子的,而10d的总萌发率与无粘液种子的没有显著差别,表明粘液物质在干旱条件下可能从种子而非外界环境中吸取水分,减缓了种子萌发速率。通过上述结果可以认为小车前种子表面的粘液物质在早春干湿交替剧烈的荒漠生境中起到通过调节水分来调节种子萌发的作用,这种萌发策略大大降低了因大批种子同时萌发导致幼苗受旱甚至种群灭亡的潜在风险。

Development and Identification of Introgression Lines from Cross of Oryza sativa and Oryza minuta

Introgression line population is effectively used in mapping quantitative trait loci（QTLs）,identifying favorable genes,discovering hidden genetic variation,evaluating the action or interaction of QTLs in multiple conditions and providing the favorable experimental materials for plant breeding and genetic research.In this study,an advanced backcross and consecutive selfing strategy was used to develop introgression lines（ILs）,which derived from an accession of Oryza minuta（accession No.101133） with BBCC genome,as the donor,and an elite indica cultivar IR24（O.sativa）,as the recipient.Introgression segments from O.minuta were screened using 164 polymorphic simple sequence repeat（SSR） markers in the genome of each IL.Introgressed segments carried by 131 ILs covered the whole O.sativa genome.The average number of homozygous O.minuta segments per introgression line was about 9.99.The average length of introgressed segments was approximate 14.78 cM,and about 79.64% of these segments had sizes less than 20 cM.In the genome of each introgression line,the O.minuta chromosomal segments harbored chromosomal fragments of O.sativa ranging from 1.15% to 27.6%,with an overall average of 8.57%.At each locus,the ratio of substitution of O.minuta alleles had a range of 1.5% 25.2%,with an average of 8.3%.Based on the evaluation of the phenotype of these ILs,a wide range of alterations in morphological and yield-related traits were found.After inoculation,ILs 41,11 and 7 showed high resistance to bacterial blight,brown planthopper and whitebacked planthopper,respectively.These O.minuta-O.sativa ILs will serve as genetic materials for identifying and using favorable genes from O.minuta.

Arbuscular mycorrhizal fungi improved plant growth and nutrient acquisition of desert ephemeral Plantago minuta under variable soil water conditions

Desert ephemeral plants play an important role in desert ecosystem.Soil water availability is considered as the major restrictive factor limiting the growth of ephemeral plants.Moreover,arbuscular mycorrhizal fungi（AM fungi） are widely reported to improve the growth of desert ephemerals.The present study aimed to test the hypothesis of that AM fungi could alleviate drought stress of desert ephemeral Plantago minuta,and AM fungal functions reduced with the improvement of soil water content.A pot experiment was carried out with three levels of soil water contents（4.5%,9.0%,and 15.8%（w/w））,and three AM inoculation treatments（Glomus mosseae,Glomus etunicatum and non-inoculation）.The results indicate that mycorrhizal colonization rate decreased with the increase of soil water availability.Inoculation improved plant growth and N,P and K acquisition in both shoots and roots regardless water treatments.When comparing the two fungi,plants inoculated with G.mosseae performed better than those inoculated with G.etunicatum in terms of plant growth and nutrient acquisition.These results showed that ameliorative soil water did not suppress arbuscular mycorrhizal fungal functions in improving growth and nutrient acquisition of desert ephemeral Plantago minuta.

Activity of Tagetes minuta Linnaeus(Asteraceae)essential oil against L3 Anisakis larvae type 1

Objective:To evaluate in vitro effects of Tagetes minuta L. essential oil(TEO) on L3 Anisakis larvae type 1. Methods:In order to evaluate the potential use of Tagetes minuta essential oil against L3 Anisakis larvae three different media were tested:1) a saline solution(SS); 2) an industrial marinating solution; 3) sunflower seeds oil(SO). For each media and concentrations of TEO(0.1%,0.5%,1.0% and 5.0% v/v),20 parasites were introduced into plastic Petri dishes(diameter 90 mm) and maintained at room temperature. As controls,larvae were maintained without TEO under identical experimental conditions in SS,MS and SO. A total of 900 larvae were tested. The normalized mean viability,LT100,LT50 and the percentage of inactivation at 24 hours were calculated. Results:In vitro tests revealed a complete inactivation of parasites in saline solution after 2 hours with 5% and 1% of TEO. In marinating solution,a complete inactivation of parasites was observed after 4 hours at all concentrations used. A slower activity for all TEO concentration was reported in SO. Conclusions:The results obtained,showing a strong activity against Anisakis larvae,confirm TEO as a larvicidal agent in the treatment of human anisakidosis and in the industrial marinating process.

Resistance of Oryza minuta to Nilaparvata lugens (Stl)

Evaluation of O. minuta for the re-sistance to the brown planthopper(BPH), Nilaparvata lugens (Stl)was carried out by using ModifiedSeedbox Screening Technique(MSST) . Based on the significtmtdifferences between O. minuta,E13-9, and the susceptible check

Anti-oxidative and anti-inflammatory effects of Tagetes minuta essential oil in activated macrophages

Objective:To investigate antioxidant and anti-inflammatory effects of Tagetes minuta(T.minuta)essential oil.Methods:In the present study T.minuta essential oil was obtained from leaves of T.minuta via hydro-distillation and then was analyzed by gas chromatography-mass spectrometry.The antioxidant capacity of T.minuta essential oil was examined by measuring reactive oxygen,reactive nitrogen species and hydrogen peroxide scavenging.The anti-inflammatory activity of T.minuta essential oil was determined through measuring NADH oxidase,inducible nitric oxide synthase and TNF-αmRNA expression in lipopolysacharide-stimulated murine macrophages using realtime PCR.Results:Gas chromatography-mass spectrometry analysis indicated that the main components in the T.minuta essential oil were dihydrotagetone(33.86%),E-ocimene(19.92%).tagetone(16.15%),cis-β-ocimene(7.94%),Z-ocimene(5.27%).limonene(3.1%)and epoxyocimene(2.03%).The T.minuta essential oil had the ability to scavenge all reactive oxygen/reactive nitrogen species radicals with IC_(50)12-15μg/mL,which indicated a potent radical scavenging activity.In addition,T.minuta essential oil significantly reduced NADH oxidase,inducible nitric oxide synthaseand TNF-αmRNA expression in the cells at concentrations of 50μg/mL,indicating a capacity of this product to potentially modulate/diminish immune responses.Conclusions:T.minuta essential oil has radical scavenging and anti-inflammatory activities and could potentially be used as a safe effective source of natural anti-oxidants in therapy against oxidative damage and stress associated with some inflammatory conditions.

Responses of <i>Marsilea minuta</i>L. to Cadmium Stress and Assessment of Some Oxidative Biomarkers

In a hydroponic based experiment, the Cd toxicity is monitored with some cellular responses of Marsilea plant. Initially, plants were grown under varying concentrations (0, 50, 100 and 200 μM of Cd) of cadmium (Cd) with supplementation of 2 mM spermidine (Spd). The oxidative stress developed by Cd overaccumulation was measured with fall in Relative Growth Rate (RGR) by 27.11% to 59.83% growth reduction over control under varying Cd treatments. The retrieval of RGR was recovered by 1.59 folds as compared to the highest concentration of Cd (200 μM) when plants were fed with Spd. A concomitant degradation of chlorophyll was recorded in dose-dependant manner, however, the retrieval was not much pronounced with Spd. On the contrary, the non-oxidant thiol had borne more clarity with ongoing Cd concentration and appeared to be 40.51% increase maximally for GSH: GSSG at the highest concentration of Cd. Spd has minimized the ratio by 27.4%. The recovery of osmotic turgidity was indexed with a sharp rise in glycine betaine by 3.86 folds maximum at the highest concentration of Cd over control which declined by 30.9% with Spd. Another cellular response of treated plants was more evident from their isozymic profiles with regard to superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPX). The intensity of protein expression was significantly variable but not in band numbers as evident from Cd treated plants. In vitro enzyme assay of catalase showed as declining trend within the limit of 33.13% to 43.22% which was reported by 1.45 folds when Spd was applied. Therefore, from the present study, the cellular responses of Marsilea plant which showed compatibility for their expression with Cd toxicity could be hypothesized as a case of bioindication.

Identification of Intergeneric Hybrid Plants Between Oryza sativa and O.minuta via GISH and RAPD

To transfer desirable resistance traits from O. minuta to O. sativa, intergeneric hybrid plants between O. sativa (AA, 2n=2X=24) and O. minuta (BBCC, 2n=4X=48) were produced by embryo rescue after sexual cross. Morphological observation and chromosome counts indicated their hybrid status (ABC, 2n=3X=36). Genomic in situ hybridization (GISH) was further applied to confirm the parentage of the chromosomes of F 1 hybrids. Chromosomes of O. minuta and O. sativa were distinguishable in the hybrids in different fluorescence colors. GISH indicated that A and BC chromosomes were not randomly assembled in a cell. RAPD profiles unequivocally revealed their hybrids with double parent patterns. The results of blast tests showed that the hybrids had obtained disease resistance from O. minuta, and had a level of susceptibility between the parents.

基于AHP-DEMATEL法的外来入侵植物风险评估指标体系确立

通过对外来物种风险评估的影响因素进行对比和筛选,统筹指标体系的科学性、重要性、实用性和可移植性,选取决定风险产生的关键因素,构建外来植物风险评估的典型指标体系。从入侵性、适生性、扩散性、危害性4个纬度建立基于AHP-DEMATEL法的外来入侵植物风险度量数学模型,用以揭示因素之间的相互依赖关系,识别并量化因素之间的直接和间接影响,并利用构建的评估体系和生态位模型对印加孔雀草在中国的风险性进行分析。结果表明:经济危害、防除难度、国内重视程度、耐逆性是导致入侵植物风险性系数升高的重要因素,印加孔雀草在我国的综合风险评估值P为0.82,属于高度风险性有害植物,需要在适生区建立监测预警体系,阻截该植物的扩散蔓延,以保护生态环境和农业可持续发展。

Characterization of interspecific hybrids and backcross progenies from a cross between Oryza minuta and Oryza sativa

Oryza minuta, a tetraploid wild relative of cultivated rice, is an important source for the genetic improvement. Interspecific hybrids were obtained from the cross of O. sativa L. (IR24) and O. minuta (Acc. No. 101133) with 5.58% crossability, which ranged from 0.11% to 1.62% in the backcross generations. The chromosome numbers of the backcross progenies were 24 to 48. Seven yield-related traits of the parents, hybrid F1, and backcross progenies were evaluated. Simple sequence repeat markers analysis showed that the polymorphism ratio of SSR bands between IR24 and Acc. No. 101133 was 93.2%. The average donor segment number, length, donor genome size, and percentage of donor genome of 92 BC3F1 plants (2n=24) were 24.1, 17.8 cM, 438.4 cM and 26.2%, respectively. They were complex variation and uneven among the chromosomes. These introgression lines could be used to identify the favorable genes of O. minuta and provide a new platform for the genetic improvement of cultivated rice.

Tagetones A and B, new cytotoxic monocyclic diterpenoids from flowers of Tagetes minuta

Tagetones A(1) and B(2), two new monocyclic diterpenoids were isolated from the n-hexane fraction of fresh flowers of Tagetes minuta L.(Asteraceae). Their structures were established by multiple spectroscopic methods(IR, HR-ESI-MS, and 1D-, and 2D-NMR), in addition to comparison with literature data. Compound 1 showed cytotoxic activity towards MCF7 and A549 cancer cells with IC_(50) values being 4.68 and 4.24 μmol·L^(-1), respectively, compared to doxorubicin(IC_(50) 0.13 and 1.12 μmol·L^(-1), respectively). Compound 2 also exhibited significant activity against HCT116 cancer cells(IC_(50), 6.30 μmol·L^(-1)).

米奴塔睡莲对弱光环境的生理生化响应

[目的]探究米奴塔(Nymphaea minuta)睡莲对弱光环境的生理生化响应,为以米奴塔睡莲为代表的微小型热带睡莲种苗繁育和盆花生产管理提供理论依据。[方法]采用完全随机试验设计,搭建不同层数遮阳网,设置遮光率0(全光照对照,CK)、30%(轻度遮光)、50%(中度遮光)和70%(重度遮光)处理。处理120 d时测定各处理米奴塔睡莲的叶片数、叶干重和叶面积等生长指标,并在遮光30、60、90和120 d时测定各处理叶片的光合色素、可溶性糖、可溶性蛋白和淀粉含量及初生代谢产物含量,分析不同遮光条件对米奴塔睡莲叶片生长状况、光合色素含量及初生代谢产物含量的影响。[结果]在遮光30~120 d期间,遮光率30%和50%处理米奴塔睡莲的平均叶面积、光合色素含量和可溶性蛋白含量与CK均无显著差异(P>0.05)。遮光120 d时,米奴塔睡莲的叶片数、平均叶干重、比叶重、可溶性糖、可溶性蛋白和淀粉含量均随着遮光率的增加而降低,总叶绿素、叶绿素a、叶绿素b、叶绿素a/b和类胡萝卜素含量均随着遮光率的增加而升高。与CK相比,遮光120 d时遮光率70%处理米奴塔睡莲的叶片数、平均叶干重和比叶重分别显著降低52.9%、81.3%和57.8%(P<0.05,下同),总叶绿素、叶绿素a、叶绿素b和类胡萝卜素含量分别显著升高108.7%、81.6%、237.5%和88.2%,叶绿素a/b显著降低39.1%,可溶性糖、可溶性蛋白和淀粉含量分别显著降低43.4%、56.2%和53.2%。相关分析结果表明,米奴塔睡莲的叶片数和平均叶干重与可溶性蛋白含量呈极显著正相关(P<0.01,下同),平均叶干重与总叶绿素、叶绿素a、叶绿素b和类胡萝卜素含量呈极显著负相关。[结论]米奴塔睡莲在遮光率为30%和50%的轻、中度遮光环境下生长状况良好,表现出良好的光适应性反应和调节能力,这2种遮光方式可在微小型热带睡莲品种种苗繁育和盆花生产管理中参考应用。

小粒野生稻内生细菌的分离鉴定和促生功能分析

小粒野生稻(Oryza minuta)是具有良好生物和非生物胁迫抗性的野生稻资源,挖掘小粒野生稻促生相关内生细菌可为其微生态研究和菌肥开发提供参考信息。本研究对小粒野生稻的根、茎和叶进行内生细菌分离,共获得85个菌株。通过促生功能分析发现,43株内生细菌具有溶磷能力,19株具有固氮作用,29株产铁载体,13株产吲哚乙酸。分离自根部的OMR2-3菌株和叶部的OML3-4菌株具有较高吲哚乙酸分泌能力,分别为17.22 mg/L和16.59 mg/L。形态学和分子鉴定显示,OMR2-3菌株和OML3-4菌株分别为阴沟肠杆菌(Enterobacter cloacae)和路德维希肠杆菌(Enterobacter ludwigii)。通过温室促生效果测定发现,2个菌株对多年生稻粳型品种PR23和籼型品种云大107具有显著促生效果,可以不同程度促进多年生稻幼苗的株高、根长、鲜质量、叶绿素和氮素含量。以上结果说明,小粒野生稻蕴含丰富的促生相关内生细菌资源,从中筛选到的内生阴沟肠杆菌OMR2-3菌株和路德维希肠杆菌OML3-4菌株具有开发成为多年生稻生物微生物菌肥的潜力,有助于多年生稻绿色轻简化的生产模式。

印加孔雀草资源开发利用综述

由于印加孔雀草精油等提取物表现出潜在生物活性,国际市场对其需求正快速增长。查阅文献资料发现国外对该植物有较长的利用史,精油等提取物的研究也较为成熟。但我国暂认定该物种为入侵种,研究时间短,主要集中在入侵生态学方面,尚不完善,特别是入侵防控方面。全球化背景下,倡导转变对该物种入侵的消除控制策略,发展有益一面,灵活运用好入侵这把“双刃剑”。本文主要综述了印加孔雀草提取物在香料、食品、化妆品、医疗、生物农药等方面的经济价值,建议将该植物在中国未来资源化开发的重点落实在挖掘其香料、化妆品原料和生物农药价值上。

印加孔雀草挥发油化学成分及生物活性研究进展

印加孔雀草为菊科万寿菊属外来入侵植物,富含单萜、倍半萜类挥发油,具有抑菌、杀虫、抗氧化、抗病毒及抗肿瘤等生物活性,在工业、农业、畜牧业、医疗及公共卫生等领域均有良好的应用前景。研究发现,采集地点、采集部位的不同都会直接影响印加孔雀草挥发油的化学成分组成及其相对百分含量,从而影响其生物活性。基于此,综合国内外研究报道,系统梳理不同来源的印加孔雀草挥发油的化学成分及药理活性,以期为印加孔雀草野生植物资源的综合开发和利用提供借鉴。

水稻孕穗期茎注射野生稻DNA变异株系的RAPD分析

利用野生稻有利基因是培育超高产栽培稻 ( Oryza sativa L,2 n=2 4 AA染色体组型 )的主要技术路线之一。本研究通过穗茎注射法将小粒野生稻 O.minuta( 2 n =4 x=4 8,BBCC染色体组型 )总DNA导入杂交稻当家亲本 V2 0 B,获得了变异株的 3个高世代株系 ;用 RAPD方法对上述 3个株系、供、受体及对照品种明恢 63共 6个材料进行了多态性研究分析。所用 83个 Operon引物均在小粒野生稻与V2 0 B间扩增出多态性产物 ,二者相似系数仅为 2 6.7% ,而明恢 63与 V2 0 B二者的相似系数达 90 .5%。83个引物中有 15个引物在变异株第 7代株系 97C- 77与受体 V2 0 B间扩增出的产物存在差异 ,差异带共有 2 6条 ,占 83个引物在 V2 0 B中扩增出的带数 397的 6.6%。其中 OPB- 18、OPD- 0 3、OPE- 0 9、OPE- 18、OPG- 10及 OPG- 11等 6个引物在 97C- 77中各扩增出 1条只在供体中存在而在受体中不存在的特异带。 2 6条差异带中的 2 4条在共第 3代祖先的第 9代 2个株系 98C- 10 7、 98C- 165与 97C- 77间无差异。因此 ,绝大多数 DNA水平上的变异可能从第 3代起稳定遗传 ;研究结果从 DNA水平证明 ,变异株系中导入了野生稻 DNA,导入野生稻

广西普通野生稻的遗传多样性及分布特征

【目的】对广西境内普通野生稻居群遗传多样性进行研究,明确广西普通野生稻遗传多样性分布与地理特征的关系。【方法】利用36对分布于水稻12条染色体上的微卫星引物对来自广西14个区域(县级行政区域)的27个居群690份普通野生稻材料进行遗传多样性分析。【结果】所有个体平均等位基因数A=9.86,有效等位基因数Ae=5.05,总遗传多样度Ht=0.74,基因分化系数Gst=0.49,说明广西普通野生稻遗传多样性丰富,且居群内与居群间的多样性对总遗传多样性的贡献相当。通过不同区域遗传多样性检测和聚类分析,在遗传一致度为0.5处可把广西普通野生稻分为3个类群。【结论】结合广西的地形及野生稻居群的分布情况,3个类群的形成与山脉的阻隔、水系的分布以及地质结构等影响基因传播途径的特征关系密切。

小粒野生稻可转化人工染色体文库初步构建及筛选

以小粒野生稻核DNA为材料构建了一个可转化人工染色体文库,获得了5000个克隆,平均插入片段约45 kb。稳定性检测结果表明,小粒野生稻基因组DNA能够在TAC载体中稳定存在。基于已克隆抗性基因的保守序列设计探针,利用菌落杂交的方法,对文库进行筛选。结果表明,该文库可以用于抗性基因的筛选。

小粒野生稻抗白叶枯病新基因的鉴定与初步定位

【目的】将小粒野生稻(Acc.No.101133)的抗白叶枯病基因导入栽培稻IR24,并对其进行鉴定和分子标记定位,以便应用于育种实践。【方法】以小粒野生稻和栽培稻IR24的BC2F2群体及其F3、F4家系为材料,利用分离集团分析法(BSA),借助SSR标记对Xa35(t)进行分子标记定位。【结果】通过对抗病基因进行抗谱鉴定和遗传分析,结果表明,该基因对白叶枯病菌株PXO86和PXO99表现感病,而对PXO61、PXO112和PXO339表现抗病,初步将其定位于水稻的第11染色体长臂上,同标记RM144共分离,并位于标记RM7654和RM6293之间,与两标记的遗传距离分别为1.1cM和0.7cM。【结论】小粒野生稻(Acc.No.101133)含有新的抗白叶枯病基因,暂定为Xa35(t)。

水稻类病变(Lesion Resembling Disease)突变体对光照和温度的诱导反应

【目的】对水稻lrd表达的光温诱导反应进行研究,明确水稻lrd表达光诱导波段和温度的抑制或促进作用。【方法】利用自有的6个水稻lrd突变体,用LED单色光源诱激和人工气候箱中不同温度梯度处理,观察类病斑的发生情况和统计病斑个数,比较诱导的效果。【结果】lrd31类病斑表达受紫外光诱导,lrd36的表达受黄光诱导,lrd37和lrd35的表达受蓝光诱导,而lrd32和lrd40在所有处理的光源下均表达类病斑;lrd32、lrd36和lrd37等3种温度下都正常产生病斑,低温明显促进病斑的发生。lrd35和lrd40在高温下不表达,在中温下可正常表达,低温下也表现促进作用,但lrd31只有在中温下正常表达,低温和高温抑制病斑出现。【结论】不同的lrd基因型所需的光诱导反应波段是不相同的。温度是抑制或促进lrd表达的另一个重要环境因子,一般是较低的温度促进lrd表达,高温抑制lrd表达。