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1.
为了解大鼠肝再生中8种肝脏细胞的丝氨酸族氨基酸代谢相关基因转录谱, 文章用Percoll密度梯度离心结合免疫磁珠分选分离大鼠的8种再生肝细胞, 用Rat Genome 230 2.0芯片等检测它们中丝氨酸族氨基酸代谢相关基因的表达变化, 用Cluster和Treeview等软件分析上述基因在肝再生中表达模式, 用生物信息学和系统生物学等方法分析上述细胞中丝氨酸族氨基酸代谢活动。结果表明, 在27个发生有意义表达变化的基因中, 肝细胞、胆管上皮细胞、卵圆细胞、肝星形细胞、窦内皮细胞、库普弗细胞、陷窝细胞、树突状细胞的基因数分别为13、16、11、14、13、11、12、14, 相应细胞的上调、下调和上/下调的基因数分别为7、6和0, 2、10和4, 2、8和1, 8、3和3, 6、5和2, 4、6和1, 2、10和0, 6、6和2。总的来看, 肝再生中各细胞的表达下调基因占优势, 但在肝再生启动阶段, 肝星形细胞和窦内皮细胞的表达上调基因占优势。上述丝氨酸族氨基酸代谢相关基因转录谱预示丝氨酸族氨基酸的合成主要在肝再生启动阶段的肝细胞、肝星形细胞、窦内皮细胞和库普弗细胞中增强, 它们的降解主要在肝再生进展阶段的肝细胞、胆管上皮细胞、陷窝细胞和树突状细胞中进行。 相似文献
2.
科尔沁沙地沙漠化过程中土壤有机碳和全氮含量变化 总被引:4,自引:1,他引:3
通过地面调查,研究了沙漠化对科尔沁沙地农田和草地土壤有机碳和全氮含量的影响.结果表明,随着沙漠化的发展,科尔沁沙地土壤碳、氮含量明显下降.和非沙漠化农田相比,轻度、中度、重度和严重沙漠化农田土壤有机碳和全氮含量分别下降12.3%和15.3%、22.2%和24.7%、39.5%和44.7%、64.4%和63.5%;和非沙漠化草地相比,轻度、中度、重度和严重沙漠化草地土壤有机碳和全氮含量分别下降了56.3%和48.7%、78.4%和74.4%、88.9%和84.6%、91.6%和84.6%.截至2000年,科尔沁沙漠化总面积已经达到50197.5 km2,由于沙漠化而导致的土壤有机碳和全氮损失总量分别为36.39 Mt和7.89 Mt,其中草地分别占91.12%和86.06%,农田分别占8.88%和13.94%.相关分析结果表明,土壤有机碳和全氮的损失主要源于风蚀所引起的土壤粘粉粒的减少.因此,在科尔沁沙地,防治土壤风蚀对于减少农田和草地土壤碳、氮损失极为重要. 相似文献
3.
华南阔叶树种幼苗叶片的养分特征 总被引:6,自引:0,他引:6
研究了阔叶树种幼苗山杜英、红锥、海南红豆、火力楠、红花油茶、枫香、黎蒴、米老排和樟树的N、P、K浓度和单位叶面积含量。结果表明,海南红豆、黎蒴和樟树的N、P、K浓度较高,而红花油茶、黎蒴和樟树的单位叶面积N、P、K含量较高,9种树种的上部和下部叶片的平均养分浓度分别为N16.67和17.09g·kg^-1,P1.29和0.84g·kg^-1,K11.77和6.65g·kg^-1,平均养分含量分别为N0.871和1.069g·m^-2,P0.065和0.052g·m^-2,K0.608和0.426g·m^-2,各树种上部叶片的P和K浓度和含量大于下部叶片,从养分含量的角度考虑,红花油茶与其他8种树种混交,红锥或米老排与山杜英、枫香、海南红豆、黎蒴、樟树混交,火力楠与黎蒴、樟树混交是合理的。 相似文献
4.
夏枯草药材和种植土壤中农药及重金属残留分析 总被引:1,自引:0,他引:1
采用气相色谱及ICP-AES法测定了安徽庐江和江苏洪泽2个种植基地的土壤和夏枯草(Prunella vulgaris L.)果穗及全草中有机氯农药及重金属含量,并根据污染指数和相关标准对土壤及药材的安全性进行了评价.测定结果表明:来源于2个基地的土壤及药材中有机氯农药及重金属含量有明显差异.庐江产果穗和全草中Pb、Cd、Cu、Cr、As及BHC含量分别为3.361和3.953、0.172和0.190、8.258和7.722、3.423和2.658、0.284和0.355、0.003和0.004 mg·kg-1,Hg和DDT未检出;洪泽产果穗和全草中Pb、Cd、Cu、Cr、Hg及BHC含量分别为2.399和1.558、0.155和0.111、7.682和6.756、4.259和3.801、0.077和0.102、0.003和0.006 mg·kg-1,As未检出,果穗中也未检出DDT.庐江基地土壤中Cd、Cu、Cr、As、Hg、BHC和DDT含量分别为0.001、12.943、47.417、1.008、0.003、0.003和0.002 mg·kg-1,Pb未检出;洪泽基地土壤中Pb、Cd、Cu、Cr、As、Hg和BHC含量分别为3.443、0.002、18.655、63.385、3.701、0.141和0.004 mg·kg-1,DDT未检出.比较结果表明:夏枯草果穗中重金属残留量均高于全草,但均低于国家限量标准;土壤中有机氯农药及重金属单项污染指数均小于1,且庐江和洪泽基地土壤的综合污染指数分别为0.286和0.399,因此,土壤污染等级属安全级且污染水平为清洁级. 相似文献
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南昌市不同植物类群叶片氮磷浓度及其化学计量比 总被引:9,自引:2,他引:9
对南昌大学前湖校区89种主要植物叶片的N、P浓度及其化学计量比进行了研究,结果表明:乔灌、常绿、针叶、种子、裸子和单子叶植物类群的N浓度分别低于相对应的草本、落叶、阔叶、蕨类、被子和双子叶植物类群,而C3和C4植物差异不显著;乔灌、常绿和裸子植物类群的P浓度含量分别低于相对应的草本、落叶和被子植物类群,而针叶和阔叶、蕨类和种子、单子叶和双子叶、C3和C4植物类群间差异不显著;乔木、阔叶、被子和双子叶植物类群叶片N/P分别高于相对应的灌草、针叶、裸子和单子叶植物类群,而常绿和落叶、蕨类和种子、C3和C4植物类群之间差异不显著.可见,不同类型植物对N和P的吸收利用存在差异,且对不同养分供应采取不同的适应对策.结合研究区土壤养分现状,建议优先选择常绿、针叶、裸子和单子叶植物类群作为城市园林植物. 相似文献
6.
黄粉虫、蝇蛆和大麦虫是市场上最常见的饲用昆虫.本试验采用或借鉴饲料营养成分测定的国家标准方法,测定了3种昆虫的常规营养成分、矿物元素、氨基酸和中长链脂肪酸的含量.结果表明,黄粉虫、蝇蛆和大麦虫的粗蛋白含量(%)依次为50.20、45.62和45.08,粗脂肪含量(%)依次为28.96、30.10和41.71,总能含量(KJ/g)依次为26.16、25.95和28.66;蝇蛆中钙、磷、铁和锰的含量(mg/100 g)最高,依次为500.0、885.7、1.17和3.06,黄粉虫中铜和锌的含量(mg/100 g)最高,分别为1.49和10.51;黄粉虫中支链氨基酸、直链氨基酸、必需氨基酸和总氨基酸的含量(%)均最高,依次为8.51、5.71、16.76和39.88,蝇蛆中苯丙氨酸、谷氨酸和赖氨酸的含量(%)较高,依次为2.71、6.29和3.19;黄粉虫中C14∶0和顺C18∶2的相对含量较高,分别为6.15%和33.17%,蝇蛆中C16∶0和C16∶1的相对含量较高,分别为39.62%和4.08%,大麦虫中C18∶0和顺C18∶1的相对含量较高,依次为23.33%和43.54%.上述结果表明,三种昆虫均具有较高的营养价值,可用于养殖业中蛋白质饲料原料的开发. 相似文献
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玫瑰(Rosa rugosa Thunb.)原产于我国东部沿海、日本、朝鲜半岛和俄罗斯远东地区,18世纪作为园艺种引入欧洲后逃逸并入侵至北海和波罗的海周边多个国家以及北美沙质海岸,而中国野生种群却在过去30年间持续萎缩,成为珍稀濒危物种。从玫瑰种群生物学角度,通过文献比较和综合,在阐明玫瑰生态学特性和野生分布变化的基础上,全面论述了玫瑰种群在我国的生境退化、种群动态、种子繁殖、遗传多样性、濒危机理、保育方面的成果和悬疑问题;并结合欧洲入侵种群分布范围和敏感生境、对本地群落和物种的影响、种子繁殖、遗传变异、种群扩张和模拟预测、管理和控制方面的研究进展,分析了濒危种群和入侵种群数量动态、群落组成、幼苗更新、遗传变异、管理策略方面的差异及其影响因素;进而提出未来的玫瑰研究可从濒危种群和入侵种群的比较研究、种群和灌丛的动态监测、适合度相关性状的变异及其遗传基础、基于种群生物学的保育或控制4个方面为切入点,集中探索玫瑰种群濒危和入侵动态的规律、遗传基础和主要驱动力,为玫瑰保育和管理提供理论依据,为相似物种的适应和进化机制研究提供例证。 相似文献
8.
江西省茶园土壤肥力特征及其影响因子 总被引:4,自引:0,他引:4
为探明江西省典型茶园土壤养分状况和肥力特征,选取江西省21个地区372个典型茶园,分析茶园土壤养分的差异性、空间性、相关性及与地形、土壤类型、海拔和建园时间的关联性。结果表明: 江西省茶园土壤pH、有机质、碱解氮、速效磷、速效钾、全氮、全磷和全钾分别达到优质高效高产茶园土壤营养指标的53.9%、60.1%、56.1%、22.9%、38.5%、43.7%、11.1%和95.5%,其中速效磷为强变异;有效铜、锌、铁、锰和硼达到土壤微量元素含量分级一级标准的占比分别为76.3%、74.2%、96.8%、73.1%和0.0%。江西茶园土壤养分以赣中地区最高,其次是赣东北和赣西北地区,赣南地区最低。除全钾外,土壤pH与有机质、碱解氮、速效磷、速效钾、全氮和全磷均呈显著正相关。不同地形土壤养分以平地最高,高山次之,山地和丘陵最低;不同土壤类型土壤养分以水稻土、砂壤和山地黄棕壤较高,其次是黄壤、红黄壤和紫色土,红壤最低;土壤pH、有机质和全钾随海拔上升而递增,而速效磷随海拔上升而递减;土壤有机质、碱解氮、全氮、速效磷和全磷随建园时间的增加而递增,而土壤pH随建园时间的增加而递减。综上,江西省茶园土壤肥力总体水平良好,有机质、全钾、有效铜、锌、铁和锰均较丰富,但土壤偏酸,速效磷和全磷偏低,有效硼严重缺乏。赣中应提高土壤pH和钾肥,赣东北增加钾和氮肥,赣西北增加有机质和磷肥,赣南应增加氮磷钾肥并配施有机肥;高山茶园补充速效磷和钾肥,山地茶园提高氮和磷肥;红黄壤茶园提高土壤pH和全钾,红壤茶园应提高氮磷钾肥并配施有机肥,黄壤和山地黄棕壤茶园需要增施磷肥,紫色土茶园需提高土壤有机质;茶园需要逐年增加白云石粉、生理碱性肥料和有机肥等,防治茶园土壤酸化。 相似文献
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八种水生植物对重金属富集能力的比较研究 总被引:37,自引:1,他引:37
通过野外采样和系统分析方法,研究了芜湖市四褐山工业区附近水域中Cu、Pb、Cd、Zn和Mn5种重金属的含量及其在8种水生植物体内的积累特性。结果表明,工业区水体污染严重,重金属含量严重超标,分别为标准值的9、10.1、400、3和438倍;8种水生植物的重金属积累量均较大,其中以水鳖根、茎叶的Cu、Pb、Cd、Zn含量最高,分别为水体中重金属浓度的9.12和2.59倍、33.41和5倍、0.8和0.3倍、26.9和9.1倍,明显高于其它7种水生植物;8种水生植物不同器官对Cu、Pb、Zn的富集系数均>1,富集能力较强。其中,香蒲对Pb、Cd的吸收能力表现为茎叶>根。结果表明,在Cu、Pb和Zn等重金属复合污染水域的植物治理中,浮萍、香蒲、水鳖、中华慈姑、芦苇、空心莲子草等植物有着较大的发展潜力和应用前景。 相似文献
11.
Marcos Fernández‐Martínez Sara Vicca Ivan A. Janssens Josep Maria Espelta Josep Peñuelas 《Ecography》2017,40(7):864-874
Weather and its lagged effects have been associated with interannual variability and synchrony of fruit production for several tree species. Such relationships are used often in hypotheses relating interannual variability in fruit production with tree resources or favourable pollinating conditions and with synchrony in fruit production among sites through the Moran effect (the synchronisation of biological processes among populations driven by meteorological variability) or the local availability of pollen. Climatic teleconnections, such as the North Atlantic Oscillation (NAO), representing weather packages, however, have rarely been correlated with fruit production, despite often being better predictors of ecological processes than is local weather. The aim of this study was to test the utility of seasonal NAO indices for predicting interannual variability and synchrony in fruit production using data from 76 forests of Abies alba, Fagus sylvatica, Picea abies, Pseudotsuga menziesii, Quercus petraea, and Q. robur distributed across central Europe. Interannual variability in fruit production for all species was significantly correlated with seasonal NAO indices, which were more prominently important predictors than local meteorological variables. The relationships identified by these analyses indicated that proximal causes were mostly responsible for the interannual variability in fruit production, supporting the premise that local tree resources and favourable pollinating conditions are needed to produce large fruit crops. Synchrony in fruit production between forests was mainly associated with weather and geographical distance among sites. Also, fruit production for a given year was less variable among sites during warm and dry springs (negative spring NAO phases). Our results identify the Moran effect as the most likely mechanism for synchronisation of fruit production at large geographical scales and the possibility that pollen availability plays a role in synchronising fruit production at local scales. Our results highlight the influence of the NAO on the patterns of fruit production across western Europe. 相似文献
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Vast amounts of cultivars of native plants are annually introduced into the semi-natural range of their wild relatives for re-vegetation and restoration. As cultivars are often selected towards enhanced biomass production and might transfer these traits into wild relatives by hybridization, it is suggested that cultivars and the wild × cultivar hybrids are competitively superior to their wild relatives. The release of such varieties may therefore result in unintended changes in native vegetation. In this study we examined for two species frequently used in re-vegetation (Plantago lanceolata and Lotus corniculatus) whether cultivars and artificially generated intra-specific wild × cultivar hybrids may produce a higher vegetative and generative biomass than their wilds. For that purpose a competition experiment was conducted for two growing seasons in a common garden. Every plant type was growing (a.) alone, (b.) in pairwise combination with a similar plant type and (c.) in pairwise interaction with a different plant type. When competing with wilds cultivars of both species showed larger biomass production than their wilds in the first year only and hybrids showed larger biomass production than their wild relatives in both study years. As biomass production is an important factor determining fitness and competitive ability, we conclude that cultivars and hybrids are competitively superior their wild relatives. However, cultivars of both species experienced large fitness reductions (nearly complete mortality in L. corniculatus) due to local climatic conditions. We conclude that cultivars are good competitors only as long as they are not subjected to stressful environmental factors. As hybrids seemed to inherit both the ability to cope with the local climatic conditions from their wild parents as well as the enhanced competitive strength from their cultivars, we regard them as strong competitors and assume that they are able to outperform their wilds at least over the short-term. 相似文献
14.
Aphrodite Tsaballa Konstantinos Pasentsis Nikos Darzentas Athanasios S Tsaftaris 《BMC plant biology》2011,11(1):46
Background
Grafting is a widely used technique contributing to sustainable and ecological production of many vegetables, but important fruit quality characters such as taste, aroma, texture and shape are known for years to be affected by grafting in important vegetables species including pepper. From all the characters affected, fruit shape is the most easily observed and measured. From research in tomato, fruit shape is known to be controlled by many QTLs but only few of them have larger effect on fruit shape variance. In this study we used pepper cultivars with different fruit shape to study the role of a pepper Ovate-like gene, CaOvate, which encodes a negative regulator protein that brings significant changes in tomato fruit shape. 相似文献15.
After fruit ripening, many fruit-tree species undergo massive natural fruit abscission. Olive (Olea europaea L.) is a stone-fruit with cultivars such as Picual (PIC) and Arbequina (ARB) which differ in mature fruit abscission potential. Ethylene (ET) is associated with abscission, but its role during mature fruit abscission remains largely uncharacterized. The present study investigates the possible roles of ET and polyamine (PA) during mature fruit abscission by modulating genes involved in the ET signalling and biosynthesis pathways in the abscission zone (AZ) of both cultivars. Five ET-related genes (OeACS2, OeACO2, OeCTR1, OeERS1, and OeEIL2) were isolated in the AZ and adjacent cells (AZ-AC), and their expression in various olive organs and during mature fruit abscission, in relation to interactions between ET and PA and the expression induction of these genes, was determined. OeACS2, OeACO2, and OeEIL2 were found to be the only genes that were up-regulated in association with mature fruit abscission. Using the inhibition of ET and PA biosynthesis, it is demonstrated that OeACS2 and OeEIL2 expression are under the negative control of PA while ET induces their expression in AZ-AC. Furthermore, mature fruit abscission depressed nitric oxide (NO) production present mainly in the epidermal cells and xylem of the AZ. Also, NO production was differentially responsive to ET, PA, and different inhibitors. Taken together, the results indicate that PA-dependent ET signalling and biosynthesis pathways participate, at least partially, during mature fruit abscission, and that endogenous NO and 1-aminocyclopropane-1-carboxylic acid maintain an inverse correlation, suggesting an antagonistic action of NO and ET in abscission signalling. 相似文献
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Each of the principal quinolizidine alkaloids (QA) found in both xylem and phloem exudates together with extracts from all component organs collected from bitter (cv. Lupini) and sweet (cv. Ultra) cultivars of Lupinus albus L. were quantified by gas chromatographic analyses throughout reproductive development. In addition to establishing the major translocated QA species estimates for fluxes of QA to developing fruits based on their sap composition and water economy showed that around half of the QA that accumulated in fruit tissues was due to synthesis in situ and half to translocation principally by phloem. Detailed analyses of QA in transport fluids and component organs were extended to reciprocal homo- and hetero-grafts using bitter (cv. Fest) and sweet (cv. Danja) cultivars of L. angustifolius L. These data confirmed that the majority of QA were synthesized in shoot tissues. In both lupin species feeding and analysis of deuterated QA (lupanine and 13-hydroxylupanine) were used as tracers to demonstrate direct redistribution of alkaloids by translocation from mature leaves in phloem. 相似文献
17.
Cohen S Tzuri G Harel-Beja R Itkin M Portnoy V Sa'ar U Lev S Yeselson L Petrikov M Rogachev I Aharoni A Ophir R Tadmor Y Lewinsohn E Burger Y Katzir N Schaffer AA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,125(2):343-353
Sweet melon cultivars contain a low level of organic acids and, therefore, the quality and flavor of sweet melon fruit is determined almost exclusively by fruit sugar content. However, genetic variability for fruit acid levels in the Cucumis melo species exists and sour fruit accessions are characterized by acidic fruit pH of <5, compared to the sweet cultivars that are generally characterized by mature fruit pH values of >6. In this paper, we report results from a mapping population based on recombinant inbred lines (RILs) derived from the cross between the non-sour 'Dulce' variety and the sour PI 414323 accession. Results show that a single major QTL for pH co-localizes with major QTLs for the two predominant organic acids in melon fruit, citric and malic, together with an additional metabolite which we identified as uridine. While the acidic recombinants were characterized by higher citric and malic acid levels, the non-acidic recombinants had a higher uridine content than did the acidic recombinants. Additional minor QTLs for pH, citric acid and malic acid were also identified and for these the increased acidity was unexpectedly contributed by the non-sour parent. To test for co-localization of these QTLs with genes encoding organic acid metabolism and transport, we mapped the genes encoding structural enzymes and proteins involved in organic acid metabolism, transport and vacuolar H+ pumps. None of these genes co-localized with the major pH QTL, indicating that the gene determining melon fruit pH is not one of the candidate genes encoding this primary metabolic pathway. Linked markers were tested in two additional inter-varietal populations and shown to be linked to the pH trait. The presence of the same QTL in such diverse segregating populations suggests that the trait is determined throughout the species by variability in the same gene and is indicative of a major role of the evolution of this gene in determining the important domestication trait of fruit acidity within the species. 相似文献
18.
Diversity of Breadfruit (
Artocarpus altilis
, Moraceae) Seasonality: A Resource for Year-Round Nutrition. Breadfruit, Artocarpus altilis (Parkinson) Fosberg, is an important but underutilized staple crop cultivated throughout Oceania and much of the wet tropics.
Indigenous peoples have selected and cultivated cultivars with different fruiting seasons to effectively extend fruit production
for most of the year. In the present study, the seasonality of 219 breadfruit accessions originating from 17 Pacific island
groups, the Seychelles, the Philippines, and Indonesia, and now growing in the National Tropical Botanical Garden’s (NTBG)
Kahanu Garden, Hana, Hawaii, were evaluated. The predominant season of male flower production for most cultivars was from
May to September, and fruit was produced most frequently between August and January. However, there were differences in the
duration of the fruiting season from year to year and among cultivars. Over the 10-year period, 14 cultivars did not reliably
produce fruit; most of this group were ‘ulu afa’ trees collected from Tokelau. About 24 cultivars exhibited very little seasonality
and produced fruit throughout the year. The rest of the cultivars could be clustered into seasonality groups with characteristic
fruiting patterns. Comparison of literature values indicates that unlike Hawaii, the breadfruit season in most locations begins
around the date the sun reaches zenith prior to the summer months and extends throughout the summer months. Five cultivars
asexually propagated from the NTBG collection growing in Kiribati (1°28′ N) exhibit similar fruiting patterns as in Hawaii,
except that they begin 2–3 months earlier. These data predict that cultivars with complementary fruiting seasons in Hawaii
may experience a temporal shift in their seasonality but will maintain their compatibility when cultivated in different locations
and could enable year-round fruit production in many regions. 相似文献
19.
20.
Inter‐annual variability of fruit timing and quantity at Nouragues (French Guiana): insights from hierarchical Bayesian analyses
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Irene Mendoza Richard S. Condit S. Joseph Wright Adeline Caubère Patrick Châtelet Isabelle Hardy Pierre‐Michel Forget 《Biotropica》2018,50(3):431-441
The timing and quantity of fruit production are major determinants of the functioning of a forest community, but simultaneous analyses of both are rare. We analyzed a ten‐year dataset (2001–2011) of fruit production for 45 tree and liana species from the Nouragues rain forest, French Guiana. We developed a hierarchical Bayesian approach to determine variation in the timing and quantity of fruit production. Our analysis accommodates missing censuses and quantifies variation at seasonal and inter‐annual scales. The fruiting peak of 22 of 45 species occurred during the peak of the rainy season, which is typical for central and eastern Amazon. The timing and quantity of fruit production varied substantially across years in most species, with greater variation in quantity than in timing. The timing of fruit production varied from continuously fruiting species to mast fruiting species that had two or more consecutive years without fruit production. Fully 40% of species were mast fruiting species. The seasonal timing and inter‐annual variation in fruiting were unrelated to seed dispersal mode across species. We saw no evidence for directional change in the level of fruit production, the timing of fruit production, or their variances; however, 10 yr is a short record for such analyses. 相似文献