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1.
长期定位施肥对丛枝菌根真菌多样性的影响   总被引:3,自引:0,他引:3  
Diversity of arbuscular mycorrhizal fungi (AMF) was investigated in a field that had received long-term fixed ferti-lization (LFF) for 26 years.There were a total of 12 treatments in triplicates with different amounts of manure,urea,calcium phosphate,and potassium chloride.Rhizosphere soil samples of maize and wheat grown in the experimental field in Shandong Province,China,were collected in September 2003 and May 2004,respectively.Arbuscular mycorrhizal fungal spores were isolated and identified using morphological characters.Mycorrhizal colonization percentage,spore density (SD),species richness (SR),relative abundance (RA),and Shannon-Weiner index (SWI) were determined.Nineteen recognized species of AMF belonging to 5 genera were identified.Long-term fixed fertilization significantly influenced colonization percentage,SR,SD,and species diversity of AMF.The adaptability of AMF to soil fertility was different among species.Species richness and SD of AMF in maize and wheat rhizosphere soils were the highest in the nonferti-lization treatment (control) and lowest in the high manure + high nitrogen treatment (M2N2).The SWI decreased as the fertilization level increased except in the low manure treatment (M1) on maize.Compared with the other treatments,Treatment M2N2 significantly reduced SD of Glomus,and the high manure + low nitrogen treatment (M2N1) significantly retarded sporulation of Scutellospora.Manure treatments stimulated sporulation of Glomus mosseae.Spore density of G.mosseae was higher in the high nitrogen + phosphorus + potassium treatment (N2PK) than in the high nitrogen + phosphorus treatment (N2P) and the high nitrogen + potassium treatment (N2K).The SD of S.pellucida was higher in Treatment N2K than Treatments N2PK and N2P.In conclusion,long-term fixed fertilization,especially with high levels of manure and N,decreased SR,SD,and colonization and changed the species composition of AMF.  相似文献   

2.
1996~1998年试验研究了大田不施肥条件下3种泡囊丛枝菌根真菌Arbuscular mycorrhizal fungi (AMF),即 Glomus mosseae(G.m)、Glomus versifome(G.v)、Sclerocystis sinousa(S.s)对玉米生长的生态效应.结果表明,AMF处理的玉米根系活力为对照的2.32~3.05倍,玉米N素吸收比对照增加24.14%~56.65%,玉米P素吸收比对照增加41.14%~78.29%,促进玉米生长发育显著;在灭菌条件下G.m、G.v、S.s处理分别比对照增产17.63%、22.91%和10.80%;而不灭菌条件下3个处理分别比对照增产10.35%、20.56%和4.53%,同时显著提高玉米的水分供应状况.  相似文献   

3.
培养基质对丛枝菌根(AM)真菌生长发育的影响   总被引:5,自引:0,他引:5  
温室条件下,以盆栽培养方法研究不同培养基质对丛枝菌根(Arbuscular Mycorrhizae,AM)真菌Glomus mosseae生长发育的影响。结果表明:不同理化性质的基质对菌根共生体生长发育的影响不同,综合考虑菌根长度、根外菌丝量及孢子数3项指标,以沙土混合物(体积比3∶1)对G. mosseae菌剂的生长发育最为有利。宿主植物菌根长度及根中的可溶性糖浓度与根外孢子数有正相关关系,而宿主植物中磷浓度与菌根真菌的生长发育也有类似的关系。说明培养基质的养分状况、水分状况、通气状况等诸多因素都会影响菌根共生体的建立和发展。宿主植物的菌根长度、根中可溶性糖浓度以及宿主植物磷浓度对菌根真菌的生长发育有显著影响。因此,工厂化AM菌剂生产中,应以沙土混合物(体积比3∶1)为生产G. mosseae菌剂的培养基质。  相似文献   

4.
铅锌矿区分离丛枝菌根真菌对万寿菊生长与吸镉的影响   总被引:3,自引:0,他引:3  
盆栽试验研究了土壤不同施Cd水平(0、20、50 mg kg-1)下,接种矿区污染土壤中丛枝菌根真菌对万寿菊根系侵染率、植株生物量及Cd吸收与分配的影响。结果表明:接种丛枝菌根真菌显著提高了Cd胁迫下万寿菊的根系侵染率和植株生物量;随着施Cd水平提高,各处理植株Cd浓度和Cd吸收量显著增加。各施Cd水平下万寿菊地上部Cd吸收量远远高于根系Cd吸收量,尤其在20 mg kg-1施Cd水平下,接种处理地上部Cd吸收量是根系的3.90倍,对照处理地上部Cd吸收量是根系的2.33倍;同一施Cd水平下接种处理地上部Cd吸收量要显著高于对照。总体上,试验条件下污染土壤中分离的丛枝菌根真菌促进了万寿菊对土壤中Cd的吸收,并增加了Cd向地上部分的运转,表现出植物提取的应用潜力。  相似文献   

5.
丛枝菌根真菌的生物多样性研究进展   总被引:10,自引:1,他引:10       下载免费PDF全文
盖京苹  冯固  李晓林 《土壤》2005,37(3):236-242
由于进化历程和生存条件的差异,丛枝菌根(AM)真菌的发生、分布和功能都具有多样性特点。本文简述了近年来AM真菌在系统分类,种的多样性和功能多样性方面的研究成果,分析了当前研究中所存在的问题和动向。  相似文献   

6.
丛枝菌根作为地球上最广泛的共生体,在各种逆境环境中发挥着重要作用.基于不同钼污染程度的钼矿区,分析了钼污染对丛枝菌根真菌侵染、繁殖及其分泌球囊霉素能力的影响.结果 表明,在4个不同钼污染级别的土壤中,丛枝菌根真菌与植物共生关系的形成未受到钼污染的影响,平均菌根侵染频度为50.64%.洛阳钼矿区土壤的平均孢子密度为19....  相似文献   

7.
本文对比了两个不同转化事件的Bt玉米品种"5422Bt1"和"5422CBCL"及其同源常规玉米"5422"丛枝菌根真菌侵染率和叶片及根系氮、磷、钾养分含量的变化,并分析了丛枝菌根真菌侵染率和养分含量的相关性。结果表明,在观测期间,两个Bt玉米品种与常规玉米之间根系丛枝菌根真菌侵染率均无显著差异,但氮、磷、钾养分含量则明显不同,丛枝菌根真菌侵染率与养分含量之间的相关性也有所改变,其变化随玉米品种、生育期以及器官不同而不同。Bt玉米"5422Bt1"在大喇叭口期叶片全钾和根系全磷、开花授粉期叶片全磷和根系全氮、乳熟期叶片全钾以及成熟期叶片全磷和根系全氮、全钾含量均显著高于常规玉米"5422",而大喇叭口期和开花授粉期叶片全氮、开花授粉期根系全磷和全钾以及乳熟期根系全钾含量则低于常规玉米"5422"。Bt玉米"5422CBCL"在大喇叭口期叶片全钾和根系全氮及全钾、开花授粉期叶片全磷以及成熟期根系全氮和全钾含量显著大于常规玉米"5422",而开花授粉期根系全磷、乳熟期根系全磷和全钾以及成熟期叶片全磷含量则小于常规玉米"5422"。相关分析表明,常规玉米"5422"和Bt玉米"5422CBCL"的丛枝菌根真菌侵染率与根系全氮含量及叶片全钾含量之间均呈显著正相关(P0.05),而Bt玉米"5422Bt1"则无显著相关性(P0.05)。可见,与常规玉米"5422"相比,Bt玉米养分含量以及丛枝菌根真菌侵染率与养分含量之间相关关系与不同转化事件所形成的品种特性有关。  相似文献   

8.
以菲和芘为多环芳烃(PAHs)代表物,以紫花苜蓿(Medicago sativa L.)为宿主植物,选用幼套球囊霉(Glomus etunicatum, Ge)、摩西球囊霉(Glomus mosseae,Gm)和层状球囊霉(Glomus lamellosum,Gla)3种丛枝菌根真菌(AMF),研究了接种AMF下土壤中AMF菌丝密度、球囊霉素含量与PAHs去除率的关系。35~75 d,接种Ge、Gm、Gla处理的土壤中菌丝密度、总球囊霉素含量、易提取球囊霉素含量均随时间延长而显著增大,与不接种对照相比,75 d时接种Ge、Gm、Gla处理的土壤中易提取球囊霉素含量提高了48.58%、55.99%和50.23%,总球囊霉素含量则提高了38.75%、50.95%和46.12%。接种AMF促进了土壤中菲和芘的去除,随着时间(35~75 d)延长,接种Ge、Gm、Gla处理的土壤中菲去除率分别高达83.4%~92.7%、82.1%~93.8%、86.9%~93.4%,芘去除率达42.2%~63.5%、43.7%~69.2%、44.6%~66.4%。接种Ge、Gm和Gla处理土壤中AMF菌丝密度、总球囊霉素含量均与土壤中菲和芘的去除率之间存在极显著正相关关系,表明接种AMF提高了土壤中AMF菌丝密度和总球囊霉素含量,并促进了土壤中PAHs的去除。研究结果为阐明丛枝菌根修复PAHs污染土壤的规律及机理提供了依据。  相似文献   

9.
为揭示冬麦免耕覆盖栽培管理措施对土壤丛枝菌根真菌多样性的影响,以农田土壤生态系统为研究对象,利用Illumina MiSeq平台通过高通量测序的方法,对连续免耕覆盖栽培及有机肥管理下冬麦土壤丛枝菌根真菌群落组成及其与土壤环境因子间的相互关系进行研究。结果表明,丛枝菌根(AM)真菌在97%相似度下共获得4 515个AM真菌的操作分类单元(OTUs),分属于1门3纲4目8科10属155种。不同处理中,类球囊霉属(Paraglomus),球囊霉属(Glomus)和近明球囊霉(Claroideoglomus)为优势属,受农业综合管理措施中有机肥施用、免耕覆盖因子的影响,近明球囊霉、有隔球囊霉属相对丰度在不同处理间存在显著差异(P<0.05)。与耕作、不覆盖相比,免耕、覆盖措施提高了AM真菌多样性指数,但降低了AM真菌属的丰富度;与无肥条件相比,有机肥施用提高了AM真菌丰富度指数,但降低了AM真菌多样性指数。多元分析结果表明,土壤全磷及速效磷含量是影响AM真菌群落组成中优势属丰度变化的主要因素。免耕覆盖、有机栽培改变了土壤AM真菌的多样性及丰富度,土壤中丰度较低的AM真菌菌属更容易受到有机肥施用的影响;有机肥与免耕、覆盖管理的交互作用对AM真菌近明球囊霉属相对丰度有显著影响(P<0.05)。AM真菌群落对耕作覆盖、有机肥施用管理活动的响应受到农业综合管理活动及其相关因素交互作用的影响。本研究结果为合理农作物免耕覆盖、有机栽培管理提供了理论依据。  相似文献   

10.
丛枝菌根真菌对玉米和续断菊间作镉吸收和累积的影响   总被引:2,自引:0,他引:2  
卢鑫  胡文友  黄标  李元  祖艳群  湛方栋  邝荣禧  何跃 《土壤》2017,49(1):111-117
通过盆栽试验,利用分室隔网培养方法,模拟研究接种丛枝菌根真菌(AMF)对玉米-续断菊(Sonchus asper L.Hill)间作体系Cd吸收和累积的影响。结果表明:1无论Cd添加到A室还是B室,玉米的侵染率都要比续断菊高出6.3%~38.35%。接种AMF之后,都不同程度地提高了玉米和续断菊的生物量,但对玉米和续断菊吸收Cd的影响有所不同。2Cd添加到A或者B室,AMF均会促进该侧植物对Cd的吸收,降低另一侧植物对Cd的吸收。3接种AMF后,续断菊对Cd的转运系数降低,玉米对Cd的转运系数有的升高有的降低。总之,AMF改变了间作条件下玉米和续断菊对Cd的吸收,菌丝在两者之间可能起着非常重要的作用。  相似文献   

11.
Interactions between arbuscular mycorrhizal fungi (AMF) and plants are essential components of ecosystem functioning; however, they remain poorly known in dry ecosystems. We examined the relationship between seven shrub species and their associated AMF community in a semi-arid plant community in southern Spain. Soil characteristics and plant physiological status were measured and related to AMF community composition and genetic diversity by multivariate statistics. We found differences in AMF communities in soils under shrubs and in gaps among them, whereas no differences were detected among AMF communities colonizing roots. Soil nutrients content drove most of the spatial variations in the AMF community and genetic diversity. AMF communities were more heterogeneous in fertile islands with low nitrogen-to-phosphorus ratio and vice versa. AMF genetic diversity increased in soils limited by phosphorus and with high soil organic matter content, while AMF genetic diversity increased in roots growing in soil not limited by phosphorus. Overall, we could not find a clear link between plant performance and the associated AMF community. Our findings show that different shrub species generate islands of fertility which differ in nutrient content and, therefore, support different AMF communities, increasing AMF diversity at the landscape level.  相似文献   

12.
ABSTRACT

Arbuscular mycorrhizal (AM) fungi can improve plant phosphorus (P) uptake; however, information about how AM fungi affect rhizosphere organic acid and microbial activity to alleviate citrus low P stress is limited. Here, a pot experiment was conducted to evaluate the effect of AM fungi (Rhizophagus intraradices, Ri) inoculation on rhizosphere organic acid content, microbial biomass (MB) and enzyme activity of trifoliate orange (Poncirus trifoliata L. Raf.) seedlings grown under three low P conditions. The results showed that mycorrhizal seedlings all recorded higher P concentrations, plant biomass and better root morphology with more lateral and fine roots, but lower root mass ratios, irrespective of P conditions. Mycorrhizal P absorption contribution did not differ significantly among three P conditions. Mycorrhizal seedling rhizosphere soil exhibited lower organic acid content, soil organic P content and ratio of MB-carbon (C)/MB-P, but higher MB and enzyme activity. Additionally, the main organic acids showed a negative relationship with mycorrhizal colonization rate and hyphal length; however, phosphatase and phytase activity had a significantly positive relationship with MB. Therefore, the results suggest that AM fungi inoculation may help citrus to efficiently utilize organic P source by improving microbial activity under low available P conditions.  相似文献   

13.
The significance of arbuscular mycorrhizal fungi (AMF) in soil remediation has been widely recognized because of their ability to promote plant growth and increase phytoremediation efficiency in heavy metal (HM) polluted soils by improving plant nutrient absorption and by influencing the fate of the metals in the plant and soil. However, the symbiotic functions of AMF in remediation of polluted soils depend on plant–fungus–soil combinations and are greatly influenced by environmental conditions. To better understand the adaptation of plants and the related mycorrhizae to extreme environmental conditions, AMF colonization, spore density and community structure were analyzed in roots or rhizosphere soils of Robinia pseudoacacia. Mycorrhization was compared between uncontaminated soil and heavy metal contaminated soil from a lead–zinc mining region of northwest China. Samples were analyzed by restriction fragment length polymorphism (RFLP) screening with AMF-specific primers (NS31 and AM1), and sequencing of rRNA small subunit (SSU). The phylogenetic analysis revealed 28 AMF group types, including six AMF families: Glomeraceae, Claroideoglomeraceae, Diversisporaceae, Acaulosporaceae, Pacisporaceae, and Gigasporaceae. Of all AMF group types, six (21%) were detected based on spore samples alone, four (14%) based on root samples alone, and five (18%) based on samples from root, soil and spore. Glo9 (Rhizophagus intraradices), Glo17 (Funneliformis mosseae) and Acau3 (Acaulospora sp.) were the three most abundant AMF group types in the current study. Soil Pb and Zn concentrations, pH, organic matter content, and phosphorus levels all showed significant correlations with the AMF species compositions in root and soil samples. Overall, the uncontaminated sites had higher species diversity than sites with heavy metal contamination. The study highlights the effects of different soil chemical parameters on AMF colonization, spore density and community structure in contaminated and uncontaminated sites. The tolerant AMF species isolated and identified from this study have potential for application in phytoremediation of heavy metal contaminated areas.  相似文献   

14.
Root colonization, abundance of spores and hyphae, as well as species diversity of arbuscular mycorrhizal (AM) fungi were analyzed in citrus orchards along an altitudinal gradient. The citrus trees were heavily colonized (50.87–77.45%) by native AM fungi. In citrus orchards located at <600 m above sea level (asl), we recorded more extensive hyphal and arbuscular colonization, and higher spore and hyphal length density. AM fungal colonization, spore density, and hyphal length density were closely correlated with edaphic factors such as available phosphorus, pH, and organic matter. A total of 18 AM fungal species belonging to 3 different orders, Archaeosporales (1 species), Diversisporales (7 species) and Glomerales (10 species), were identified on the basis of spore morphological characteristics. In orchards located at higher altitudes (≥700 m asl), we observed a significant decrease in species richness and Shannon–Wiener index values. However, in all of the surveyed orchards, Glomus aggregatum, Funneliformis mosseae and Rhizophagus intraradices were the dominant species. Isolate frequency and relative abundance of AM fungi exhibited clearly distinct distribution patterns among taxonomic families. Canonical correspondence analysis revealed that the AM fungal community structure was significantly influenced by environmental factors, especially altitude, pH, soil moisture, and available nitrogen. Our data indicated that environmental factors are important in determining AM fungal root colonization, propagule numbers, and species diversity in citrus orchards.  相似文献   

15.
丛枝菌根真菌对棉花耐盐性的影响研究   总被引:17,自引:2,他引:17       下载免费PDF全文
盆栽灭菌试验研究丛枝(AM)真菌对棉花耐盐性的影响结果表明,自然盐渍化土壤和人工模拟盐渍条件下接种AM真菌处理的生物产量显著高于不接种处理,相同土壤下菌根真菌对棉花植株生长的促进作用随盐水平的提高而增大,表明AM真菌与植株建立的共生关系有利于棉花在盐渍土壤中生长。盐胁迫下棉花植株对P的需要量增加,接种AM真菌可提高植株含P量,促进植株生长,提高棉花的耐盐性。  相似文献   

16.
Arbuscular mycorrhizal (AM) fungi form associations with most land plants and can control carbon, nitrogen, and phosphorus cycling between above- and belowground components of ecosystems. Current estimates of AM fungal distributions are mainly inferred from the individual distributions of plant biomes, and climatic factors. However, dispersal limitation, local environmental conditions,and interactions among AM fungal taxa may also determine local diversity and global distributions. We assessed the relative importance of these potential controls by collecting 14,961 DNA sequences from 111 published studies and testing for relationships between AM fungal community composition and geography, environment, and plant biomes. Our results indicated that the global species richness of AM fungi was up to six times higher than previously estimated, largely owing to high beta diversity among sampling sites. Geographic distance, soil temperature and moisture, and plant community type were each significantly related to AM fungal community structure, but explained only a small amount of the observed variance. AM fungal species also tended to be phylogenetically clustered within sites, further suggesting that habitat filtering or dispersal limitation is a driver of AM fungal community assembly. Therefore, predicted shifts in climate and plant species distributions under global change may alter AM fungal communities.  相似文献   

17.
转Bt基因作物对丛枝菌根真菌的影响研究进展   总被引:1,自引:0,他引:1  
在过去的十年里,世界范围内转基因作物尤其是抗虫性转Bt基因作物的品种和种植面积迅速增加。同时,转Bt基因作物的环境安全性评价问题成为人们关注和研究的热点。丛枝菌根真菌(AMF)是生态系统中普遍存在的土壤微生物,能与绝大多数植物种类形成共生关系,在农业生态系统中起重要作用。转Bt基因作物环境释放后,其与AMF问的共生关系是否受所转入Bt基因的影响,以及影响机制需要及时研究。为此,综述了转Bt基因作物与AMF共生特征方面的研究进展,并根据Bt毒素发生的空间和时间规律提出了危害机制以及转Bt基因植物的规模化种植将降低农田系统中的AMF的生物多样性的观点。  相似文献   

18.
【目的】丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)能够促进作物养分的吸收及生长,且对土壤砷污染有一定的抗性。磷石膏(phosphogypsum,PG)因含有丰富的磷、硫等养分可以为作物生长提供必要的养分,同时也可能带来砷污染的风险。【方法】为了探讨接种AMF对云烟87生长的影响以及磷石膏农用可能引起的砷污染风险,通过盆栽模拟试验研究了不同PG添加量(0和40 g/kg以PG0、PG40表示)和接种不同AMF[不接种None mycorrhizal(NM)、接种G.mosseae丛枝菌根真菌(GM)、接种G.aggregatum丛枝菌根真菌(GA)]对云烟87苗期生长及其磷、硫、砷吸收的影响。【结果】试验结果表明:无论接种与否,PG40处理的云烟87植株磷含量、吸收量及吸收效率均显著增加,其地上部硫含量及吸收量也显著增加;除NM处理外,添加PG均显著增加了云烟87根系的硫含量、硫吸收量及吸收效率,并显著增加了其植株的生物量。相同PG添加水平下,与NM处理相比,接种GM显著增加了云烟87根系的磷、硫吸收效率和植株的磷、硫含量及吸收量,另外,GM处理显著降低了其地上部砷含量及吸收量但显著增加了其植株的磷砷吸收比。在PG0处理下,接种GA显著增加了云烟87植株的磷含量及吸收量,并显著增加了其地上部硫含量及吸收量。在PG40处理下,接种GA显著增加了云烟87根系的硫含量和吸收量以及植株的生物量。无论是否添加PG,接种GA不同程度地降低了云烟87地上部砷含量和吸收量从而增加了其地上部的磷砷吸收比。【结论】在所有复合处理中,以添加磷石膏40 g/kg和接种GM对云烟87生长的促进效果较好,对施用磷石膏造成的砷污染有一定程度的抵御作用。  相似文献   

19.
Communities of arbuscular mycorrhizal fungi (AMF) are strongly affected by land use intensity and soil type. The impact of tillage practices on AMF communities is still poorly understood, especially in organic farming systems. Our objective was to investigate the impact of soil cultivation on AMF communities in organically managed clay soils of a long-term field experiment located in the Sissle valley (Frick, Switzerland) where two different tillage (reduced and conventional mouldboard plough tillage) and two different types of fertilization (farmyard manure & slurry, or slurry only) have been applied since 2002. In addition, a permanent grassland and two conventionally managed croplands situated in the neighborhood of the experiment were analyzed as controls. Four different soil depths were studied including top-soils (0–10 and 10–20 cm) of different cultivation regimes and undisturbed sub-soils (20–30 and 30–40 cm). The fungi were directly isolated from field soil samples, and additionally spores were periodically collected from long-term trap culture (microcosm) systems. In total, >50,000 AMF spores were identified on the species level, and 53 AMF species were found, with 38 species in the permanent grassland, 33 each in the two reduced till organic farming systems, 28–33 in the regularly plowed organic farming systems, and 28–33 in the non-organic conventional farming systems. AMF spore density and species richness increased in the top-soils under reduced tillage as compared to the ploughed plots. In 10–20 cm also the Shannon–Weaver AMF diversity index was higher under reduced tillage than in the ploughed plots. Our study demonstrates that AMF communities in clay soils were affected by land use type, farming system, tillage as well as fertilization strategy and varying with soil depth. Several AMF indicator species especially for different land use types and tillage strategies were identified from the large data set.  相似文献   

20.
Arbuscular mycorrhizal fungus (AMF) can enhance plant growth and resistance to toxicity produced by heavy metals (HMs), affect the bioavailability of HMs in soil and the uptake of HMs by plants, and thus has been emerged as the most prominent symbiotic fungus for contribution to phytoremediation. A greenhouse pot experiment was conducted to assess the effect of Glomus versiforme BGC GD01C (Gv) on the growth and Cd accumulation of Cd-hyperaccumulator Solanum nigrum in different Cd-added soils (0, 25, 50, 100 mg Cd kg−1 soil). Mycorrhizal colonization rates were generally high (from 71% to 82%) in Gv-inoculated treatments at all Cd levels. Gv colonization enhanced soil acid phosphatase activity, and hence elevated P acquisition and growth of S. nigrum at all Cd levels. Moreover, the presence of Gv significantly increased DTPA-extractable (phytoavailable) Cd concentrations in 25 and 50 mg Cd kg−1 soils, but did not affect phytoavailable Cd in 100 mg Cd kg−1 soil. Similarly, inoculation with Gv significantly increased Cd concentrations of S. nigrum in 25 and 50 mg Cd kg−1 soils, but decreased Cd concentrations of the plants in 100 mg Cd kg−1 soil. Overall, inoculation with Gv greatly improved the total Cd uptakes in all plant tissues at all Cd levels. The present results indicated that S. nigrum associated with Gv effectively improved the Cd uptake by plant and would be a new strategy in microbe-assisted phytoremediation for Cd-contaminated soils.  相似文献   

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