紫薇品种与尾叶紫薇种间杂交亲和性研究

通过杂交结果率比较和荧光显微观察对5个紫薇(Lagerstroemia indica)品种与尾叶紫薇(L.caudata)杂交亲和性进行研究.结果显示:(1)以紫薇品种作母本与尾叶紫薇进行杂交(正交),'白云映霞'结果率最高,达36.6%,而'粉蝴蝶'×尾叶紫薇未结果.以尾叶紫薇作母本时(反交),各紫薇品种均可结果,结果率为16.6%～51.8%.(2)荧光观察发现,尾叶紫薇花粉在紫薇雌蕊上萌发和生长受到一定的阻碍,表现为授粉后柱头乳突细胞产生大量胼胝质反应,花粉管生长过程中出现较多胼胝质栓塞等;而紫薇的花粉在授粉1 h后即可在尾叶紫薇柱头上萌发,8 h花粉管伸入子房,10 h完成受精.研究表明,各正交组合的亲和性有明显差异,存在受精前障碍,而反交组合亲和性较好,不存在受精前障碍.     

SPME-GC/MS 联用分析六堡茶茶花香气成分

该研究采用顶空固相微萃取—气相色谱/质谱联用技术,对六堡本地三种茶树花的香气成分进行了分析。结果表明：大叶种茶树花中共鉴定出香气成分37种,主要为苯乙酮、4-甲基-1,5-庚二烯、苯甲酸甲酯、愈创木二烯、顺式芳樟醇氧化物、雪松烯、水杨酸甲酯、D-杜松烯、1-氨基-环戊醇、除虫菊酮,占总相对含量的89.48％;中叶种共鉴定出32种成分,主要为苯乙酮、紫苏烯、顺式-3-蒈烯、顺式α-榄香烯、苯甲酸乙酯、塞瑟尔烯、α-蒎烯、新丁香三环烯、衣兰烯、顺式芳樟醇氧化物,占总相对含量的83.88％;小叶种的茶树花中共鉴定出45种香气成分,主要为苯乙酮、紫苏烯、罗勒烯、顺式α-榄香烯、2-异丙基-5-甲基-9-亚甲基-二环[4.4.0]癸-1-烯、荜澄茄油烯醇、α-菖蒲二烯、α-红没药烯、衣兰烯、苯甲酸乙酯、白菖油萜和α-杜松烯,占总相对含量的82.34％。苯乙酮为三种茶树花共有的主要成分,分别占总相对含量的60.70％、42.46％和39.91％,这成分与其他成分一起构成了3个品种明显不同的茶树花花香。该研究结果为六堡茶树花的深加工提供了依据。     

垂丝海棠花蕾和花挥发性成分研究

采用顶空固相微萃取和气质联用技术(HS-SPME-GC-MS),首次分析了垂丝海棠花蕾和花的挥发性成分。从样品中共分析鉴定出68种组分,其中花蕾63种组分,花中24种组分,有19种组分共有。烷烃类化合物是花蕾和花的主要成分(花蕾:34.87%;花:37.48%);酯类化合物在花蕾中的含量高于花(花蕾:2.34%,花:0%),而酸类、醇类化合物在花蕾中的含量却远低于花(花蕾:12.86%、7.19%,花:31.49%、7.76%),这说明在花的开放过程中,酯类化合物被相关的酶水解成相应的酸和醇。     

三白草花、叶和茎挥发性成分的比较分析

采用顶空固相微萃取提取三白草花、叶和茎中的挥发性成分,利用GC-MS对比分析三者中的挥发性成分.从三白草花、叶和茎分别鉴定出的31、22和22个成分,分别占总挥发性成分的95.64％、98.75％和98.54％.三者共有18个化学成分,其主要化合物类型是萜类(单萜和倍半萜,其中单萜含量最高),分别占总挥发性成分的92.18％、98.19％和97.74％,还含有两个芳香族化合物:枯茗醇和姜黄烯,此外,4-(1,5-二甲基己基-4-烯)环己烯-2-酮和二十一烷两个脂肪族化合物仅存在于花中,三者的主要化合物均为柠檬烯、柠檬醛(含顺式柠檬醛)、蒎烯(含α和β构型)和β-月桂烯,另外大根香叶烯D、姜黄烯、1-b-红没药烯和β-倍半水芹烯在花中的含量均高于叶和茎.叶茎中化合物种类和含量差别均不大,但与花有较大的差别.     

不同类型梅花品种挥发性成分的研究

用GC-MS分析梅花(Prunus mume)5个品种(三轮玉蝶、北京玉蝶、单瓣玉、淡粉和江南朱砂)花朵中的挥发性成分,从中鉴定出45个化合物,其中芳香族化合物是主要成分.不同类型的梅花品种香气成分不同,这些化合物种类和含量的变化导致不同类型的梅花品种花香差异,一些重要的共有成分乙酸己酯、丁子香酚、乙酸苯甲酯和α-蒎烯等化合物的存在是导致梅花品种花香相似的主要原因.     

顶空固相微萃取-气相色谱-质谱联用法分析香花秋海棠及其变种花香气成分

利用顶空固相微萃取结合气相色谱-质谱联用技术对盛花期的香花秋海棠(Begonia handelii)雄花及其变种铺地秋海棠(B. handelii var. prostrata)雌花和红毛香花秋海棠(B. handelii var. rubropilosa)雄花的挥发性香气成分进行分析。结果表明,从铺地秋海棠花中鉴定出香气成分32 种,其中醇类物质含量最高,占总成分50.10,其次分别为碳氢类、醛类和酸类物质,分别占总成分25.39、13.87、4.34;从香花秋海棠花中鉴定出香气成分为21种,醛类物质含量最高,占总成分57.12,其次是醇类、碳氢类、杂环类物质,分别占总成分17.37、15.31、4.88;从红毛香花秋海棠花中鉴定出香气成分44 种,醇类物质含量最高,占总成分38.22,其次是碳氢类、醛类和醚类物质,分别占总成分34.36、16.83、6.91。铺地秋海棠和红毛香花秋海棠香气成分较接近,富含具有清香、甘甜气息的芳樟醇氧化物等物质;香花秋海棠花中醛类物质含量最高,具有淡焦甜香气。     

我国4种红茶的挥发性成分分析

为了解我国4种名优红茶挥发性成分的异同,采用全自动顶空固相微萃取结合气相色谱-质谱分析,对滇红、祁红、正山小种和金骏眉的挥发性成分进行了研究。结果表明,4种红茶中共鉴定出挥发性成分90种,滇红茶中主要是芳樟醇、香叶醇、芳樟醇氧化物、水杨酸甲酯、2-戊基呋喃和橙花叔醇,祁红中主要是十六碳酸、植酮、香叶醇、芳樟醇氧化物、β-紫罗酮、植醇和蒽等,正山小种中主要是植酮、香叶醇、β-紫罗酮、二氢猕猴桃内酯、咖啡因和芳樟醇氧化物,而金骏眉中主要是香叶醇、咖啡因、芳樟醇氧化物、β-紫罗酮、苯乙醇、橙花叔醇和植醇;他们共同成分有苯甲醛、苯乙醛、芳樟醇氧化物、芳樟醇、香叶醇、α-紫罗酮、β-紫罗酮、植醇等。4种红茶在挥发性组成及含量上差异较大,共有成分仅32种;醇类化合物含量均较高,其中滇红茶中醇类化合物含量高达69.08%;而祁红、正山小种和金骏眉中酮类化合物含量较高。不同化合物之间比例和阈值的不同,形成了4种红茶各自独特的香气特征。     

铁观音加工工序中的香气成分分析

采用顶空固相微萃取（HS-SPME）法分别萃取了铁观音堆青、炒青、烘焙三个工序中产生的香气,用气质连用仪（GC／MS）对这些香气进行定性定量分析。在 SPME 所收集的铁观音堆青、炒青、烘焙工序所产生的香气成分中分别鉴定出22、32和19种主要香气成分。其中,2-乙烯基-1,1-二甲基-3-亚甲基环己烷、苯乙腈、吲哚、2-乙基己醇、癸醛均出现在三道工序的香气中。     

不同产地丁香挥发性成分分析

采用顶空固相微萃取-气相色谱-质谱联用技术对产自国内外4个地区的丁香(Eugenia caryophyllata Thunb.)挥发性成分进行了检测,并以峰面积归一化法计算了各组分的相对含量。结果显示,从4个产地13批次丁香中共鉴定出挥发性成分72种(匹配度均高于75),其中,主要成分含量排名前两位的均为丁香酚、(-)-α-芹子烯,排名第三位的挥发性成分分别为:顺式-α-没药烯(马达加斯加塔马塔夫,平均为3.75%)、罗勒烯(中国广东,平均为4.21%)、亚麻三烯(中国广西,平均为3.74%)、丁香烯(印度尼西亚爪哇岛,平均为3.60%)。表明同一产地的丁香挥发性成分具有一定的相似性,不同产地丁香挥发性成分也有一定的差异,这对丁香产地的鉴别具有重要意义。主成分分析和聚类分析的结果既可以将4个产地的丁香很好地区分开来,又能反映出它们之间的亲缘关系。本研究采用HS-SPME-GC-MS方法检测不同产地丁香挥发性成分并结合主成分分析(PCA)及聚类分析法,能有效区分4个产地的丁香,该方法可作为丁香产地的鉴别方法,也为进一步比较不同产地丁香挥发性成分的差异及质量控制提供了新思路。     

HS-SPME-GC-MS分析蒟酱叶挥发性成分

首次采用顶空固相微萃取和气质联用技术(HS-SPME-GCMS),结合保留指数法,用峰面积归一化法测定蒟酱叶中挥发性成分及相对百分含量。结果表明,从蒟酱叶中鉴别出27个化学成分,占峰面积的97.53%,化合物结构类型包括醛、酸、酯、酚、烯烃、芳香烃和(环)烷烃。2-甲氧基-5-甲基苯甲醛(42.89%)、胡椒酚醋酸酯(12.49%)、异丁香酚(13.42%)、4-烯丙基-1,2-二乙酰氧基苯(9.47%)、胡椒酚(2.89%)、γ-毕橙茄烯(2.74%)、丁香酚(2.66%)和乙酸异丁香酚酯(2.06%)是蒟酱叶的主要挥发性成分。     

修剪措施对紫叶紫薇花蕾中内源激素和碳氮营养含量的影响

为探讨修剪措施对二次开花的紫叶紫薇花蕾中内源激素和碳氮营养含量的影响,为指导紫叶紫薇花期调控提供理论依据,该研究以‘丹红紫叶’为试验材料,在一次花的末花期对主花枝进行重度修剪,以不进行修剪为对照(CK),分析不同处理下紫叶紫薇花蕾中主要花发育时期的吲哚乙酸(IAA)、脱落酸(ABA)、赤霉素(GA₃)、玉米素核苷(ZR)、可溶性糖、淀粉、全氮含量的变化。结果表明：(1)修剪处理后,紫叶紫薇花蕾中内源ZR含量在各花发育时期显著升高;内源GA₃含量在花芽分化期降低,在初花期至末花期显著升高;内源IAA含量在花芽分化期显著升高,在初花期至末花期降低;内源ABA含量变化不显著。(2)修剪处理后,紫叶紫薇花蕾可溶性糖含量较对照组先升高后降低,在末花期变化达到显著水平;其淀粉、全氮含量增加但未达到显著水平。(3)紫叶紫薇花蕾中碳氮比总体呈上升趋势,修剪处理后其碳氮比值小幅度提高。研究认为,修剪措施能够影响紫叶紫薇内源激素水平变化,并通过调控碳水化合物与全氮含量影响花蕾中碳氮营养代谢,从而促进了紫叶紫薇二次成花、花期延长。     

松乳菇Lactarius deliciosus与红汁乳菇L. hatsudake子实体内可培养细菌多样性的研究

分离松乳菇Lactarius deliciosus与红汁乳菇L.hatsudake子实体内可培养的细菌,进行分类鉴定,为后期细菌与乳菇的相互作用研究奠定基础。利用传统平板法分离培养乳菇子实体内的细菌,进行16S r DNA片段的扩增和测序及系统发育树的构建和物种多样性分析。从松乳菇中获得66株细菌,红汁乳菇中获得48株细菌。松乳菇子实体内细菌隶属于3个门6个属10个种,其中变形菌门的γ-变型菌纲为优势类群,占细菌总数的77.28%,β-变形菌纲的Pandoraea和拟杆菌门的金黄杆菌属Chryseobacterium分别占细菌总数的12.12%和10.6%。红汁乳菇子实体内共分离、鉴定出细菌3个门7个属7个种,其中变形菌门中的γ-变型菌纲为优势类群,占细菌总数的77.09%,厚壁菌门的芽胞杆菌属Bacillus和拟杆菌门的金黄杆菌属Chryseobacterium分别占细菌总数的14.58%和8.33%。松乳菇与红汁乳菇子实体内存在一定种类和数量的细菌,其中荧光假单胞菌Psedomonas fluorescens和美洲爱文氏菌Ewingella americana为优势细菌。     

印度梨形孢对铁皮石斛种子萌发和原球茎生长的影响

为探究印度梨形孢(Piriformospora indica)对铁皮石斛(Dendrobium officinale)种子萌发和原球茎生长的影响,在铁皮石斛种子离体培养和原球茎生长阶段分别接种印度梨形孢,对其形态发育特征和生理特性进行研究.结果表明,接种印度梨形孢的铁皮石斛种子的起始萌发时间提前,接种印度梨形孢的铁皮石...     

A polysaccharide from Lichina pygmaea and L. confinis supports the recognition of Lichinomycetes

The lichen-forming order Lichinales, generally characterized by prototunicate asci and the development of thalli with cyanobacteria, has recently been recognized as a separate class of ascomycetes, Lichinomycetes, as a result of molecular phylogenetic studies. As alkali and water-soluble (F1SS) polysaccharides reflect phylogeny in other ascomycetes, a polysaccharide from Lichina pygmaea and L. confinis was purified and characterized to investigate whether these F1SS compounds in the Lichinomycetes were distinctive. Nuclear magnetic resonance (NMR) spectroscopy and chemical analyses revealed this as a galactomannan comprising a repeating unit consisting of an α-(1→6)-mannan backbone, mainly substituted by single α-galactofuranose residues at the O-2- or the O-2,4- positions linked to a small mannan core. With the exception of the trisubstituted mannopyranose residues previously described in polysaccharides from other lichens belonging to orders now placed in Lecanoromycetes, the structure of this galactomannan most closely resembles those found in several members of the Onygenales in Eurotiomycetes. Our polysaccharide data support molecular studies showing that Lichina species are remote from Lecanoromycetes as the galactofuranose residues are in the α-configuration. That the Lichinomycetes were part of an ancestral lichenized group can not be established from the present data because the extracted polysaccharide does not have the galactofuranose residue in the β configuration; however, the data does suggest that an ancestor of the Lichinomycetes contained a mannan and was part of an early radiation in the ascomycetes.     

Isolation of pure compound R/J/3 from Pluchea indica (L.) Less. and its anti-amoebic activities against Entamoeba histolytica

The plant Pluchea indica is known for its anti-inflammatory, anti-ulcer, anti-pyretic, hypoglycemic, diuretic and anti-microbial activities besides many other pharmacological activities. We have isolated and purified seven compounds from the methanolic root extract of this plant by column chromatography. The compounds were identified by spectroscopic analyses. The anti-amoebic activities of the pure compound R/J/3 was investigated against the HM1 strain of Entamoeba histolytica. The compound, R/J/3 showed the most pronounced anti-proliferative activity at a dose of 50 microg/ml. It also showed a marked activity on cell lysis of trophozoites, 4h after administration. The cell lytic activity was compared with metronidazole (5 microg/ml) as positive control.     

Kinetics of ammonium, nitrate and phosphorus uptake by Canna indica and Schoenoplectus validus

Canna indica L. is an upright perennial rhizomatous herb, and Schoenoplectus validus (Vahl) A. Löve and D. Löve is a tall, perennial, herbaceous sedge. The nutrient uptake kinetics of C. indica and S. validus were investigated using the modified depletion method after plants were grown for 4 weeks in simulated secondary-treated wastewater. The maximum uptake rate (I_max) and Michaelis–Menten constant (K_m) were estimated by iterative curve fitting. The I_max for NH₄N (623 μmol g⁻¹ dry root weight h⁻¹) was significantly higher than that for NO₃N (338 μmol g⁻¹ dry root weight h⁻¹) in S. validus. In contrast, no difference was observed in C. indica. The I_max values for NO₃N and NH₄N were higher in S. validus than in C. indica. A significantly lower K_m was detected for NO₃N uptake in C. indica (385 μmol L⁻¹) compared to that in S. validus (1908 μmol L⁻¹). The I_max for PO₄P did not differ between the plant species. The K_m for PO₄P was significantly higher in C. indica (157 μmol L⁻¹) than in S. validus (60 μmol L⁻¹). In conclusion, we found that S. validus preferred NH₄N over NO₃N, had greater capacity for N uptake and higher affinity for PO₄P, but C. indica had greater affinity for NO₃N. Nutrient uptake capacity is likely related to habitat preference, and is influenced by the structure of roots and rhizomes.     

Phylogeographic patterns in Leccinum sect. Scabra and the status of the arctic-alpine species L. rotundifoliae

We investigated inter- and intraspecific phylogenetic relationships in the ectomycorrhizal fungal genus Leccinum section Scabra. Species of this section are exclusively associated with Betula and occur throughout the Northern Hemisphere. We compared the phylogenetic relationships of arctic, alpine, boreal and temperate accessions of section Scabra based on DNA sequences of the single-copy nuclear gene Gapdh and the multiple-copy nuclear region 5.8S-ITS2. Exclusively arctic lineages were not detected in species that occur both in arctic-alpine or boreal regions, except in L. rotundifoliae that was restricted to cold climates. L. scabrum and L. holopus showed an intercontinental phylogeographic pattern, and L. variicolor showed a pattern unrelated to geographical distribution. Molecular clock estimates indicated that L. rotundifoliae is as old as other species in section Scabra. Individual gene trees suggest that interspecific hybridisation occurred several times in the evolution of section Scabra.     

Effect of lectins from Opuntia ficus indica cladodes and Moringa oleifera seeds on survival of Nasutitermes corniger

Biodegradation by termites is a serious problem for wood and crop industries worldwide, and new environmentally friendly alternatives for termite control have been developed. This work investigated the effects of crude and purified preparations containing lectins from Opuntia ficus indica cladodes (OfiL) and Moringa oleifera seeds (WSMoL and cMoL) on Nasutitermes corniger workers and soldiers. Purified OfiL was more active than cladode extracts, showing a stronger termiticidal activity against workers (LC₅₀ of 0.116 mg ml⁻¹) than against soldiers. OfiL was active against soldiers only at 1.5 mg ml⁻¹. All preparations containing WSMoL and cMoL were active only at concentrations of 1.0 and 1.5 mg ml⁻¹. The tested preparations did not exert repellent activity against N. corniger. OfiL was able to kill workers and therefore is potentially a new tool for N. corniger control; as a consequence, this lectin could disturb organization, structure, and maintenance of termite colonies.     

内生真菌印度梨形孢诱导小麦抗根腐病作用研究

【目的】明确印度梨形孢(Piriformospora indica)诱导小麦对根腐病产生抗性的作用机制。【方法】用印度梨形孢悬液浸种,以无菌培养液为对照,用病原菌禾谷镰孢菌(Fusarium graminearum)侵染小麦,对其相关生理生化指标及转录组变化进行分析。【结果】禾谷镰孢菌能诱导小麦产生过氧化氢,降低细胞内水含量,破坏细胞膜的稳定性;根部定殖印度梨形孢的小麦细胞内抗氧化酶活性增强,活性氧自由基含量降低,胞内水含量提高,细胞膜稳定性增强;印度梨形孢定殖能改变由于病原菌引起的mRNA转录组变化,抗性相关基因的表达增强。综合表明印度梨形孢定殖能有效地提高小麦对禾谷镰孢菌的抗性。【结论】研究结果为深入理解植物与微生物互作、开发新型高效环保抗根腐病生物制剂提供理论和实验依据。     

印度梨形孢(Piriformospora indica)增强植物抗逆境胁迫能力的研究进展

印度梨形孢是一种可在多种植物根部定殖的内生真菌,能与多种植物形成共生体,提高植物对外界营养的吸收能力,促进次生代谢产物的积累,提高植物对生物及非生物胁迫的抵抗能力,同时可增加植物的生物产量,对宿主植物产生许多有益影响。因此,印度梨形孢作为优良的生物防治和土壤改良因子,在农业生产方面显示出巨大的应用前景。本文结合本课题组近年研究结果及近10年间相关科学工作者的研究,系统总结了印度梨形孢在增强植物抗生物胁迫与非生物胁迫方面的研究进展,旨在为更好地发挥其潜在价值提供参考。