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1.
茶小绿叶蝉危害乌龙茶茶树品种的挥发物分析   总被引:1,自引:0,他引:1  
为明确茶小绿叶蝉危害不同抗性茶树品种后挥发物的变化,从而为抗虫茶树品种的选育提供依据,本研究选择小绿叶蝉危害虫口密度最大和最小的乌龙茶茶树品种肉桂和铁观音为材料,以GC-MS为研究手段,进行茶树组成型和虫害诱导型挥发物的测定和分析。结果表明,邻异丙基苯甲烷、β-罗勒烯、反式-β-罗勒烯、α-法呢烯、γ-萜品烯和3-甲基-2-环己烯-1-酮为铁观音和肉桂的主要组成型挥发物成分。2个品种在健康茶树挥发物的成分组成和各组分的含量上都存在差异。芳樟醇只在铁观音的健康茶梢中被检测到,而十三(碳)烷、乙酸辛酯、十六烷和雪松醇只在肉桂的健康茶梢上检测到。β-月桂烯、β-罗勒烯、反式-β-罗勒烯和α-法呢烯在铁观音上的含量远远大于肉桂。另一方面,茶树受小绿叶蝉危害一段时间后,铁观音和肉桂在挥发物组成和含量上产生了较大的变化。二者都释放大量的β-月桂烯、β-罗勒烯、反式-β-罗勒烯、α-法呢烯和芳樟醇,在危害4 h和8 h的挥发物测定中,2个品种的这些成分较危害前的增加量从1.49倍到41.22倍。此外,茶小绿叶蝉的危害还诱导了新的挥发物的产生,包括(Z)-丁酸-3-己烯酯、癸醛、吲哚、己酸-3-己烯酯和苯乙醇。(Z)-丁酸-3-己烯酯、癸醛、吲哚、己酸-3-己烯酯、苯乙醇、β-月桂烯、β-罗勒烯、反式- β-罗勒烯、α-法呢烯和芳樟醇,这10种挥发性物质可能跟茶树的诱导抗性和铁观音的抗虫性有关。  相似文献   

2.
信阳毛尖茶芳香成分研究进展   总被引:1,自引:0,他引:1  
本文叙述了茶叶香气成分分类、形成机理和绿茶香气成分提取、分析方法,引出信阳毛尖茶香气成分形成的诸多因素,分析出信阳毛尖特征香气成分主要有:苯乙烯、α-雪松醇、α-蒎烯、δ-杜松烯、甲苯、戊醇、苯甲醇、苯乙醇、2-乙基己醇、橙花叔醇、反香叶醇、芳樟醇、橙花醇、反式植醇、庚醛、壬醛、苯甲醛、β-环柠檬醛、6-甲基-5-庚烯-2-酮、紫罗酮、5,6-环氧基紫罗酮、Z-茉莉酮、2,2,6-三甲基环己酮、棕榈酸、2-乙基呋喃、己酸顺式-3-己烯酯、2-乙基吡咯等。  相似文献   

3.
不同成熟度菠萝果实香气成分分析   总被引:4,自引:0,他引:4  
用菠萝巴厘品种8成熟和9成熟的果实为材料,采用顶空同相微萃取法(HS-SPME)提取其中的香气成分,并经气相色谱,质谱(GC/MS)联机分析.结果显示,在8成熟果实中检测到13种香气成分,其中酯类10种,烯类2种,苯类1种;在酯类中,相对含量最高的是己酸甲酯(50.89%),其次是己酸乙酯(16.11%)、2-甲基丁酸甲酯(8.68%)、辛酸甲酯(5.23%)和辛酸乙酯(2.40%);检测到2种烯类成分,分别为(E)-3,7-二甲基-1,3,6辛三烯(5.18%)和à-蒎烯(0.65%);还检测到甲苯(0.32%).在9成熟果实中检测到2类共27种香气成分,分别是酯类17种和烯类10种:在酯类中,相对含量最高的是辛酸甲酯(25.27%),其次是辛酸乙酯(21.00%)、己酸乙酯(17.64%)、己酸甲酯(14.34%);在烯类中相对含量较高的有β-顺式-罗勒烯(1.00%)、à-蒎烯(0.81%)和反式-罗勒烯(O.48%).此外,仅在9成熟果实中检测到菠萝特征香气成分3-甲硫基丙酸甲酯,其相对含量为1.36%.说明9成熟菠萝果实香气成分比8成熟的丰富,且此时特征香气成分形成:如果非远距离运输,9成熟是鲜食菠萝的理想采收成熟度.  相似文献   

4.
龙眼采后果皮细胞壁代谢相关酶活性的变化   总被引:1,自引:0,他引:1  
以广东主栽龙眼品种“石硖”和“储良”为试材,研究了在3 ̄4℃贮藏条件下龙眼果皮中细胞壁代谢相关酶活性的变化。结果表明:储良龙眼果皮比石硖的衰老更快、更严重;储良果皮中的果胶甲酯酶(PME)活性比石硖的高,出现上升的时间早;储良果皮中的多聚半乳糖醛酸酶(PG)、木聚糖酶(Xyl)、β-半乳糖苷酶(β-Gal)活性也高于石硖的,外切半乳糖醛酸酶(exo-PG)活性开始上升的时间也比石硖的早。  相似文献   

5.
新型花茶的香气特征研究   总被引:1,自引:1,他引:0  
司辉清  沈强  庞晓莉 《茶叶科学》2010,30(3):167-172
研究新型花茶的香气特征及其化学组成,采用感官审评法和超临界CO2萃取法,并结合气相色谱-质谱仪联用技术,对香气特征和精油成分进行了分析鉴定。结果表明,新型花茶的香气具有馥郁高雅、芬芳持久、茶香协调的特征,从其精油中共分离出121个峰,分析鉴定出103种成分,占总面积的99.51%。相对含量较高的8种成分为:邻苯二甲酸二异丁酯(8.81%)、大根香叶烯D-4-醇(6.28%)、β-芳樟醇(3.39%)、二十一烷(3.58%)、四甲基环癸二烯甲醇(2.76%)、茉莉酮酸甲酯(2.31%)、库毕醇(2.24%)、二十烷(2.23%)。4-甲基-反式-3-硫杂双环[4.4.0]葵烷、环氧化马兜铃烯、1-氯十八烷、3-十二烷基-2,5-呋喃二酮等成分属首次分离。  相似文献   

6.
利用GC/MS技术分析罗勒(Ocimum basilicum L.)、台湾罗勒(Ocimum tashiroi Hayata)和丁香罗勒(Ocimum gratissimum)成龄叶的香气成分。结果表明:3个罗勒品种的叶片中香气成分的种类和含量存在明显差异:罗勒中检出37种香气物质,占其总挥发性物质的91.15%;台湾罗勒中检出21种香气物质,占95.08%;丁香罗勒中有29种,占89.49%。其中,烃类和醇类2类化合物在3种罗勒叶片中分别占挥发物总量的84.39%、78.61%和77.88%。β-蒎烯是3种罗勒共有的主要香气成分,桉树脑、茴香脑和环葑烯则分别是罗勒、台湾罗勒和丁香罗勒的主要香气成分。  相似文献   

7.
采用顶空固相微萃取结合气质联用对凤凰单丛八仙品种干茶和茶汤香气成分进行研究,并比较了干茶与茶汤在香气组分上的差异。结果表明,干茶和茶汤香气成分差异较大,干茶的香气成分主要是己醛、脱氢芳樟醇、1-戊烯-3-醇、β-月桂烯、D-柠檬烯等;茶汤的香气成分主要是3,7,11-三甲基-1,6,10-十二烷三烯-3-醇、顺式茉莉酮、邻苯二甲酸二异丁酯、β-紫罗兰酮等。  相似文献   

8.
研究龙眼石硖和储良2个品种的花部形态、开花生物学特性、花粉形态特征及萌发率、花粉量、P/O值、柱头可授性及其黏液分泌情况。结果显示,二者花部特征相似,储良花期较石硖长;二者的花粉形态相似,储良的花粉较石硖稍大,萌发率较石硖高;P/O值说明龙眼为专性异交植物;石硖和储良花粉活力和柱头可授性是同步变化的,尤其在盛花期花粉活力趋于最大,柱头分泌黏液与柱头可授性变化也一致,都在柱头展开成水平,开花约48 h达到最大。  相似文献   

9.
采用搅拌棒吸附萃取(SBSE)技术结合气相色谱质谱联用(GC-MS)分析了6个代表性紫芽茶中的挥发性成分。结果表明,紫芽茶中具有丰富的挥发性成分,化合物种类和数目高于对照绿茶;芳樟醇、香叶醇、α-松油醇、α-紫罗酮、β-紫罗酮、(E, E)-2, 4-庚二烯醛、水杨酸甲酯、邻甲氨基苯甲酸甲酯、二氢猕猴桃内酯和对乙酰氨基苯酚等化合物是紫芽茶中含量最丰富的香气成分。相对气味活性值(ROAV)分析表明,β-大马士酮、β-紫罗酮、反式-2,4-癸二烯醛、2-己烯醛、α-紫罗酮和芳樟醇等6种香气成分可能是紫芽茶中一些关键的致香成分;另外,1-辛烯-3-醇、二氢猕猴桃内酯、正己醛、正癸醛、β-环高柠檬醛、反式-2-壬醛、正庚醛、β-环柠檬醛和正辛醛等9种成分可能对紫芽茶的整体香气具有重要的修饰作用。  相似文献   

10.
香气是影响茶叶品质的重要因子.本试验通过对6个不同茶树品种白牡丹的香气测定,分析白牡丹的主要香气成分以及品种对白茶香气的影响.经SDE提取、GC-MS测定表明,6个茶树品种白牡丹的主要香气成分为芳樟醇及其氧化物(26.92%-51.36%)、4-甲基-2,6二叔丁基苯酚(6.35%-12.92%)、苯乙醛(2.81%-11.74%)、棕榈酸正丁酯(1.83%-3.88%)、十八烷9,12,15-三烯酸甲酯(1.34%-3.09%)、1,2苯二甲酸-2-乙基己酯(1.61%-3.48%)等.  相似文献   

11.
Pasture legumes are important components of both mixed farming rotations and permanent pastures in temperate climates. Breeding of two widely sown pasture legumes, subterranean clover (Trifolium subterraneum L.) and French serradella (Ornithopus sativus Brot.), is constrained by the long generation cycle, typically enabling only one generation per year. We hypothesized manipulation of culture medium and conditions would enable the development of a laboratory‐based protocol for in vitro reproduction in subterranean clover and French serradella. In vitro flowering and viable seed set was induced from both species. For subterranean clover, the most effective treatment was culturing on modified MS medium with 1 μm kinetin and 0·1 m sucrose under a 100 μmol m?2 s?1 light intensity and continuous photoperiod. For French serradella, culture on a hormone‐free B5 medium with 5 mm NH4Cl and 0·1 m sucrose under a 100 μmol m?2 s?1 light intensity and 20 h photoperiod was optimum. It is expected this technique will have application in accelerating generation turnover within breeding programs, for the study of factors influencing flowering in pasture legumes, and for the propagation of valuable yet enfeebled plants such as embryo‐rescued hybrids.  相似文献   

12.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

13.
Evaluation of crop and forage yield stability is of increasing relevance in the context of current and recent environmental changes but, in contrast to other field crops, there are no published systematic analyses among forage crops in Europe. A study of stability performance was conducted with 13 Czech cultivars of lucerne at four locations over a 2‐year period with the following aims: (a) to evaluate yield stability of varieties across different environments and (b) to calculate measurable benefits of variety selection in relation to the specific environment. The cultivar Vlasta was identified as the highest yielding cultivar (annual yield 16.0 t DM/ha), whereas the lowest yielding cv. Magda, Tereza and Oslava averaged around 14.9 t DM/ha. Effect of genotype × environment interaction (G × E) was two times higher than for genotype alone. Additive main effects and the multiplicative interaction (AMMI) model showed that the highest yielding cultivars may not be stable across environments. This study demonstrated further that significant yield improvement could be detected, even among a relatively homogenous group of domestic cultivars, and this was driven mainly by site productivity: the improvement was +10% in low‐yielding sites, compared with +3% in high‐yielding sites. Results highlight that advanced agronomy should also consider stability parameters such as AMMI stability value or superiority measures for forage crops in response to the challenges associated with climate change.  相似文献   

14.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

15.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

16.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

17.
东南亚、南亚地区是世界上重要的稻米产区,稻米在民众饮食生活和国家社会政治中占有重要地位,民众生活中也保存了非常悠久和丰富的稻作文化习俗及稻谷起源神话传说。本文分析了水稻在东南亚、南亚主要国家印度、印度尼西亚、泰国、越南、菲律宾、孟加拉国、缅甸的作用、地位、生产、消费、文化等情况,并指出了印度、印度尼西亚稻文化的主要标志。  相似文献   

18.
Plains rough fescue ( F estuca hallii) is an important forage grass species in western Canada. Seed for use in pastures and ecological restoration is in high demand but supply is limited because F. hallii is an erratic seed producer. Seed producers require an understanding of the factors that influence flowering and seed set in this species. The aim of this study was to assess the effect of irrigation and nitrogen fertilization on the flowering and growth of F. hallii in a native rough fescue prairie in Alberta, Canada. Irrigation had a strong positive effect on seedhead density, whereas fertilization had limited effects on growth and reproduction of F. hallii. These results demonstrate that under field conditions, available moisture is likely to be a key factor driving flowering and seed production in F. hallii.  相似文献   

19.
Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.  相似文献   

20.
A general model of crop yield response to herbicide application is proposed. The model includes three components: the effect of herbicide dosage on weed density, the effect of surviving weed density on crop yield and the effect of herbicide directly on the crop. The model is used to estimate the response of wheat yield to application of diclofop-methyl to control ryegrass (Lolium rigidum) in Australia. It is found that the competitiveness of ryegrass plants surviving treatment is reduced by the treatment and that the proportion of yield loss at a given ryegrass density is not independent of the absolute weed-free yield. The response function is used to calculate economic thresholds and optimal herbicide dosages.  相似文献   

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