首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Although it is usually admitted that arbuscular mycorrhizal (AM) fungi are key components in soil bio-functioning, little is known on the response of microbial functional diversity to AM inoculation. The aims of the present study were to determine the influence of Glomus intraradices inoculum densities on plant growth and soil microflora functional diversity in autoclaved soil or non-disinfected soil. Microbial diversity of soil treatments was assessed by measuring the patterns of in situ catabolic potential of microbial communities. The soil disinfection increased sorghum growth, but lowered catabolic evenness (4.8) compared to that recorded in the non-disinfected soil (6.5). G. intraradices inoculation induced a higher plant growth in the autoclaved soil than in the non-disinfected soil. This AM effect was positively related to inoculum density. Catabolic evenness and richness were positively correlated with the number of inoculated AM propagules in the autoclaved soil, but negatively correlated in the non-disinfected soil. In addition, after soil disinfection and AM inoculation, these microbial functionality indicators had higher values than in the autoclaved or in the non-disinfected soil without AM inoculation. These results are discussed in relation to the ecological influence of AM inoculation, with selected fungal strains and their associated microflora on native soil microbial activity.  相似文献   

2.
原生动物与解磷微生物协同解磷作用   总被引:3,自引:0,他引:3  
磷是农业生产重要的限制因素之一,土壤生物包括原生动物和微生物在土壤磷素转化过程中起着重要的作用。通过纯培养和土壤培养试验发现,供试的原生动物能够提高磷矿粉的有效磷,土壤有效磷含量也显著增加。所溶解出来的磷很大一部分以无机磷酸盐的形式贮藏在细胞内,熏蒸时才释放出来,少部分磷转化为生物量磷。原生动物与解磷菌之间没有显著的相互促进作用。  相似文献   

3.
溶磷菌和固氮菌溶解磷矿粉时的互作效应   总被引:13,自引:0,他引:13  
采用4株溶磷菌(Lx81、Dm84、Jm92、Lx191)、和3株固氮菌(ChW5、ChW6、ChO6)单独和混合接种后测定培养液有效磷含量、pH值及总有机酸含量的方法,研究溶磷菌和固氮菌溶解磷矿粉时的互作效应。结果表明,相对于单独接种溶磷菌:Lx81与3株固氮菌分别混合培养能提高磷矿粉的溶解能力,4株溶磷菌与ChW6,Lx81、Dm84、Lx191与Ch06分别混合培养及Jm92+ChW5组合溶磷量极显著增加(P〈0.01);Dm84+ChW5、Lxl91+ChW5、Jm92+Ch06组合的溶磷量下降(P〈0.01)。除Lx81+ChW6、Lx81+Ch06培养液pH值降低外,混合培养的其它组合培养液pH值均较单独接种溶磷菌时升高。有机酸测定结果表明,Lx81、Jm92与ChW5、Ch06分别混合培养、ChW6+Lx81组合有机酸含量升高(P〈0.01),其它7种组合的有机酸含量均较单独接种溶磷菌的值下降(P〈0.01)。溶磷菌和固氮菌单菌培养时溶磷量与pH值、溶磷量与总有机酸含量及pH值与总有机酸含量之间呈现线性相关;Dm84、Lx191与3株固氮菌分别混合培养溶磷量与pH值之间、Lx81与3株固氮菌分别混合培养溶磷量与总有机酸含量之间呈现线性相关,其它组合的溶磷量与pH值、总有机酸含量间没有相关性。溶磷菌和固氮菌混合培养对溶解磷矿粉既有协同作用也有拮抗作用。  相似文献   

4.
A pot experiment was conducted to investigate the uptake of Zn from experimentally contaminated calcareous soil of low nutrient status by maize inoculated with the arbuscular mycorrhizal (AM) fungus Glomus caledonium. EDTA was applied to the soil to mobilize Zn and thus maximize plant Zn uptake. The highest plant dry matter (DM) yields were obtained with a moderate Zn addition level of 300 mg kg?1. Plant growth was enhanced by mycorrhizal colonization when no Zn was added and under the highest Zn addition level of 600 mg kg?1, while application of EDTA to the soil generally inhibited plant growth. EDTA application also increased plant Zn concentration, and Zn accumulation in the roots increased with increasing EDTA addition level. The effects of inoculation with Gcaledonium on plant Zn uptake varied with Zn addition level. When no Zn was added, Zn translocation from roots to shoots was enhanced by mycorrhizal colonization. In contrast, when Zn was added to the soil, mycorrhizal colonization resulted in lower shoot Zn concentrations in mycorrhizal plants. The P nutrition of the maize was greatly affected by AM inoculation, with mycorrhizal plants showing higher P concentrations and P uptake. The results indicate that application of EDTA mobilized soil Zn, leading to increased Zn accumulation by the roots and subsequent plant toxicity and growth inhibition. Mycorrhizal colonization alleviated both Zn deficiency and Zn contamination, and also increased host plant growth by influencing mineral nutrition. However, neither EDTA application nor arbuscular mycorrhiza stimulated Zn translocation from roots to shoots or metal phytoextraction under the experimental conditions. The results are discussed in relation to the environmental risk associated with chelate-enhanced phytoextraction and the potential role of arbuscular mycorrhiza in soil remediation.  相似文献   

5.
研究了热胁迫(40℃,18 h)后在60 d培养期内不施物料(S)、仅施尿素(N)、仅施秸秆(R)和二者配施(RN)处理下土壤微生物生物量及土壤功能(基础呼吸、基质诱导呼吸、秸秆分解能力)的变化.结果表明:热胁迫有促进土壤微生物生物量及功能的趋势,但其影响弱且持续时间短.不论热胁迫与否,与不施物料和仅施氮肥处理相比,施用秸秆及其与氮肥配施处理下土壤微生物生物量、基础呼吸、基质诱导呼吸和秸秆分解能力均大幅提高,而单施氮肥处理与不施物料处理相比变化不明显,各项指标甚至有降低趋势.表明施用秸秆及其与氮肥配施对自然土壤和环境胁迫(干扰)后土壤功能都有改善作用.  相似文献   

6.
香蕉根际土壤解磷细菌的筛选、鉴定及解磷能力   总被引:4,自引:0,他引:4  
【目的】以磷矿粉为难溶态磷,以期从香蕉根际土壤筛选出高效的解磷细菌。【方法】采用透明圈法和钼锑抗比色法分离筛选解磷细菌,通过形态学特征、生理生化试验结合16S rRNA基因序列分析及系统发育树比对鉴定其种属,并利用单因素试验方法研究不同碳源、氮源及C/N比值(40:1、20:1和8:1)对菌株溶解磷矿粉能力的影响。研究不同菌株解磷能力和培养介质pH值的变化关系。【结果】分离具有解磷能力的细菌8株,筛选出具有代表性的3个菌株B3-5-6、M-3-01和T1-4-01,初步鉴定菌株B3-5-6为嗜气芽孢杆菌(Bacillus aerophilus),M-3-01为虫内生沙雷氏菌(Serratia nematodiphila),T1-4-01为艾博丽肠杆菌(Enterobacter asburiae)。B3-5-6解磷能力与介质pH值之间存在线性负相关性(|r|=0.949 66>0.735),其相关性达到极显著水平;B3-5-6在碳源为蔗糖、氮源为(NH4)2SO4、C/N为40:1,M-3-01在碳源为葡萄糖、氮源为(NH4)2SO4、C/N为20:1,T1-4-01在碳源为乳糖、氮源为蛋白胨、C/N为20:1条件下解磷效果较好。解磷效果与初筛相比分别提高了1.12、1.17、2.55倍。【结论】不同的碳氮源、C/N值会直接影响磷细菌的解磷能力;筛选出一株解磷能力与培养介质pH之间存在着极显著相关性的细菌,其解磷机理有待进一步研究。  相似文献   

7.
为了揭示油松-根系微生物的互作关系及其对油松林分稳定性的影响,本研究选择陕西省黄龙县天然和人工油松林,采集油松根际与非根际土壤,测定非根际土壤化学特性,分离纯化根际土壤解磷(有机磷和无机磷)细菌,通过DNA基因测序鉴定解磷细菌,并测定解磷细菌的解磷能力。结果表明: 天然油松林非根际土壤中全碳(TC)、全氮(TN)含量以及C/N、N/P极显著高于人工油松林。2种油松根际土壤中共鉴定出20属65种解磷细菌,其中以芽孢杆菌属、链霉菌属和假单胞菌属为优势菌群;天然油松林根际解磷细菌多样性、丰富度和均匀度指数均高于人工油松林,而优势度指数低于人工油松林。链霉菌属与非根际土壤TC、TN和C/N、N/P呈正相关,而芽孢杆菌属和假单胞菌属与非根际土壤硝态氮、铵态氮、有效磷及全磷含量呈正相关。2种油松林根际土壤不同解磷细菌的解磷能力存在差异,其中天然和人工油松林根际共有的解磷细菌为假单胞菌Pseudomonas sp.34-5,其对磷酸钙的解磷能力最高,为11.40 μg·mL-1;天然油松林根际独有的解磷细菌蕈状芽胞杆菌BF1-5对卵磷脂的解磷能力最高,为4.58 μg·mL-1。该林区2种油松林根际解磷细菌菌群结构存在显著差异。与人工油松林相比,天然油松林根际土壤解磷细菌群落多样性更丰富且分布更均匀,解磷能力普遍高于人工林。  相似文献   

8.
Survival of the ectomycorrhizal fungal strain Suillus collinitus Sc-32 on Pinus halepensis after inoculation and outplanting was monitored in a Mediterranean plantation. Three molecular fingerprints were developed: RFLP of the internal transcribed spacer ribosomal DNA, intersimple sequence repeat, and a specific sequence-characterized amplified region marker. The inoculant was demonstrated to survive on inoculated seedlings 4 years after outplanting (56 months after inoculation), although S. collinitus was not fruiting. The designed markers set allows reliable and inexpensive monitoring of inoculated seedlings and suggests that S. collinitus is suitable for inoculation of Mediterranean Pinus. These data are discussed in the framework of suilloid population ecology.  相似文献   

9.
蚯蚓和秸秆对铜污染土壤微生物类群和活性的影响   总被引:3,自引:0,他引:3  
试验设置4个Cu浓度水平:0、100、200和400 mg·kg-1 Cu2+,每个Cu浓度水平设置4个处理:对照(CK)、表施秸秆(M)、接种蚯蚓(E)、同时加入蚯蚓和秸秆(ME),研究了在Cu污染土壤中加入蚯蚓和秸秆对土壤微生物数量及活性的影响.结果表明:Cu污染、秸秆和蚯蚓均明显影响土壤微生物类群; Cu污染对细菌、放线菌具有抑制作用,而对真菌没有影响;秸秆显著提高了真菌数量;蚯蚓使土壤细菌、放线菌数量显著增加,而对真菌数量影响不大.Cu污染浓度>200 mg·kg-1处理对微生物量碳具有抑制作用;加入秸秆或蚯蚓,可显著提高土壤微生物量碳,而且同时加蚯蚓和秸秆处理土壤微生物量碳增加最显著.加入蚯蚓和秸秆后,土壤呼吸值显著增高.Cu<200 mg·kg-1时,蚯蚓处理土壤呼吸值最大,平均比对照高3.06~5.58倍;Cu≥200mg·kg-1时,蚯蚓、秸秆同时加入处理土壤呼吸值最高.4个处理土壤代谢商大小顺序为:ME>E>M>CK.蚯蚓和秸秆处理对土壤NH4+-N没有影响,而对土壤NO3--N影响各异.接种蚯蚓,可显著提高土壤NO3--N含量;加入秸秆,可显著降低土壤NO3--N含量;同时加入蚯蚓和秸秆处理NO3--N含量最低.相关分析表明,土壤有效态Cu(DTPA-Cu)与土壤放线菌、细菌呈显著负相关,而与土壤呼吸、土壤NO3--N、NH4+-N含量呈显著正相关.引入秸秆和蚯蚓,可在一定程度上减缓Cu污染对微生物数量和活性的影响.  相似文献   

10.
S. Banik  B. K. Dey 《Plant and Soil》1982,69(3):353-364
Summary Among several phosphate-solibilizing micro-organisms isolated from an alluvial soil (Fluvaquent) in sucrose-Ca3(PO4)2 agar plates, two fungal strains, ACF2 (Aspergillus candidus) and ACF1 (A. fumigatus) two bacterial strains, ACB5 (Bacillus firmus B-7650) and ACB6 (B. firmus B-7651) and one actinomycete strain, ACS6 (Streptomyces sp.) were efficient solubilizers, solubilizing 297.0, 288.3, 49.0, 45.8 and 29.0 μg of P as free PO4 −3, respectively, containing 15 mg insoluble P from Ca3(PO4)2 in broth. Solubilization was lesser from AlPO4 and FePO4. The isolates producing oxalic and tartaric acids without or with citric acid showed higher ability of solubilizing insoluble inorganic phosphates. All the above isolates possessed the ability of solubilizing rock phosphate in considerable amounts, ACF1 (A. fumigatus) being the highest (31.5 μg), while ACB6 (B. firmus B-7651) and both the aspergilli also possessed cellulose-decomposing ability in addition. Inoculation of the isolates, in a flask culture experiment, had no significant effect on the accumulation of available phosphorus in soil even when amended with rock phosphate (RP), farm yard manure (FYM), (FYM+RP), rice straw (RS) and (RS+RP). Nevertheless, the overall performance of ACF2 (A. candidus) and ACB6 (B. firmus B-7651) was better than that of the others, in this respect, while ACB5 (B. firmus B-7650) and ACF1 (A. fumigatus) intensified the enhancing effect of FYM and RS. Partial sterilization, by autoclaving, of the soil had no significant effect on available phosphorus content of the soil irrespective of any inoculation.  相似文献   

11.
石灰性土壤拉恩式溶磷细菌的筛选鉴定及溶磷特性   总被引:3,自引:0,他引:3  
从山西石灰性土壤作物根际分离筛选出多株溶磷细菌,经过多次分离纯化得到一株溶磷能力较强的菌株W25,通过菌落形态、生理生化特性和16S rRNA序列分析,确定溶磷菌W25为拉恩式菌属.对W25溶解磷特性进一步研究表明:其对磷酸三钙、磷酸铝和磷酸铁最高溶磷能力分别为385.5、110.4、216.6 mg·L-1;在磷酸铝和磷酸铁培养液中,W25溶磷量与培养液pH的相关系数分别为0.56和0.81,呈极显著负相关;在不同碳氮源条件下,W25以葡萄糖为碳源和NH4NO3为氮源时对磷酸三钙的溶磷量最高,对碳源的利用顺序依次为葡萄糖>乳糖>蔗糖>甘露醇>淀粉,对氮源的利用顺序依次为NH4NO3 >NH4Cl>(NH4)2SO4>NaNO3>KNO3.不同氮源对W25产生有机酸的种类影响较大,以铵态氮为氮源产生甲酸和乙酸,以硝态氮为氮源产生草酸和琥珀酸,以硝酸铵为氮源还产生柠檬酸.  相似文献   

12.
Colonisation of Pinus halepensis roots by GFP-tagged Pseudomonas fluorescens Aur6 was monitored by epifluorescence microscopy and dilution plating. Aur6-GFP was able to colonise and proliferate on P. halepensis roots. Co-inoculation with the ectomycorrhizal fungus Suillus granulatus did not affect the bacterial colonisation pattern whereas it had an effect on bacterial density. Bacterial counts increased during the first 20 days of seedling growth, irrespective of seedlings being mycorrhizal or not. After 40 days, bacterial density significantly decreased and bacteria concentrated on the upper two-thirds of the pine root. The presence of S. granulatus significantly stimulated survival of bacteria in the root elongation zone where fungal colonisation was higher. The number of mycorrhizas formed by S. granulatus was not affected by co-inoculation with Aur6-GFP. Neither Aur6-GFP nor S. granulatus stimulated P. halepensis development when inoculated alone, but a synergistic effect was observed on seedling growth when bacteria and fungus were co-inoculated.  相似文献   

13.
Abstract

The process of primary growth in 2-year-old seedlings of 11 populations of Pinus halepensis Mill. is described. At the end of the first growing season one type of apical structure was observed: type-1, a tuft of primary needles placed close together, surrounding and protecting a meristematic apex.

At the end of the 2nd growing season, three types of apical structure were observed: type-1; type-2, a terminal winter bud; and type-3; a «bud» with characteristics of both type-1 and type-2.

Morphological observation along with an anatomical examination of the winter bud led to the conclusion that the definitive growth pattern in juvenile P. halepensis is monocyclic with a variable number of summer shoots. This growth pattern is reached by some P. halepensis populations in 3–4 years, by contrast, in other pine species two years are usually needed.

The populations studied differed both in growth potential (differences in number of cycles, ratio of first cycle to total growth, growth rates) and in the developmental stages of the apical meristem.

Four groups could be identified: (i) Morocco and Spain, (a limited growth, few cycles, a high ratio of 1st cycle to total growth, and growth in 2nd season almost entirely due to free growth); (ii) Algeria and Greece, (moderate to low growth, a large number of cycles, a low ratio of 1st cycle to total growth, and very early formation of apical structure with preformed primordia); (iii) Israel and Central Italy (a high growth, a large number of cycles, a medium ratio of 1st cycle to total growth, and early formation of apical structure with preformed primordia); (iiii) Greece, France and Italy, which was intermediate between group (i) and the other 2 groups.  相似文献   

14.
Zimpfer  J. F.  Kaelke  C. M.  Smyth  C. A.  Hahn  D.  Dawson  J. O. 《Plant and Soil》2003,254(1):1-10
The effects of soil biota, Frankia inoculation and tissue amendment on nodulation capacity of a soil was investigated in a factorial study using bulked soil from beneath a Casuarina cunninghamiana tree and bioassays with C. cunninghamiana seedlings as capture plants. Nodulation capacities were determined from soils incubated in sterile jars at 21 °C for 1, 7, and 28 days, after receiving all combinations of the following treatments: ± steam pasteurization, ± inoculation with Frankia isolate CjI82001, and ± amendment with different concentrations of Casuarina cladode extracts. Soil respiration within sealed containers was determined periodically during the incubation period as a measure of overall microbial activity. Soil respiration, and thus overall microbial activity, was positively correlated with increasing concentrations of Casuarina cladode extracts. The nodulation capacity of soils inoculated with Frankia strain Cj82001 decreased over time, while those of unpasteurized soils without inoculation either increased or remained unaffected. The mean nodulation capacity of unpasteurized soil inoculated with Frankia CjI82001 was two to three times greater than the sum of values for unpasteurized and inoculated pasteurized soils. Our results suggest a positive synergism between soil biota as a whole and Frankia inoculum with respect to host infection.  相似文献   

15.
Ishac  Y. Z.  El-Haddad  M. E.  Daft  M. J.  Ramadan  E. M.  El-Demerdash  M. E. 《Plant and Soil》1986,90(1-3):373-382
Summary The effect of seed inoculation withAzotobacter spp. orAzospirillum spp., and garbage amendment (0.5%), on the growth of wheat was studied in a field experiment under sub-tropical conditions. Two levels of N fertilizer were applied, the usual field rate (150 kg N ha–1) and half this amount. Tillering of plants, dry matter contents and nitrogenase activity were determined 30, 60 and 90 days after sowing. At the end of the experimental period, spore numbers and percentage of mycorrhizal infection were observed in the rhizosphere and root systems of plants. Straw and grain yields were also determined. The results of this study showed that seed inoculation and/or organic amendment stimulated plant growth, nitrogenase activity and mycorrhizal infection. This was more noticeable withAzotobacter than withAzospirillum. Inoculation withAzotobacter together with 1/2 N dose and organic amendment was the most effective application (19.75 and 10.70 t ha–1 were recorded for straw and grain yield, respectively).  相似文献   

16.
Aims: In this study, 10 putative plant growth-promoting rhizobacteria (PGPR) were assayed for their ability to improve Pinus pinea growth and mycorrhization. Methods and Results: After an inoculation assay, except for two, all strains stimulated plant growth. All bacteria altered rhizosphere microbial communities as revealed by phospholipid fatty acid analysis; associating plant growth promotion with a decrease in biological diversity. Three strains were tested for their ability to enhance pine mycorrhization with wild fungi species. Only strain BB1 increased the total number of mycorrhizal root tips. Mycorrhizas present in the roots of each treatment were identified by ribosomal RNA sequencing and denaturing gradient gel electrophoresis analysis, detecting specificity between mycorrhizal species colonizing the roots and the inoculated PGPR. Conclusions: In conclusion, BB1 appears to be a good candidate to be developed into a biofertilizer directed to enhance pine growth and mycorrhization, which should result in a better establishment rate for plants used in reforestation. Significance and Impact of the Study: This study shows the potential of PGPR to improve fitness of forest tree specie. Moreover, the specificity between the bacteria inoculated and the mycorrhiza that the plant selects involve a potential biotechnological use in production of value-added fungi.  相似文献   

17.
Summary The optimum conditions for growth ofFrankia sp. HFPCcI3 isolated fromCasuarina cunninghamiana, were studied in batch culture using defined media. Maximum growth (doubling time was 24 h)_was achieved at 33°C and at pH 6.3 with pyruvate and NH 4 + as the sole C and N sources, respectively. Removal of NH 4 + from the culture medium resulted in vesicle differentiation which was paralleled by induction of acetylene reduction activity. Growth on atmospheric N2 was optimal with combined pyruvate and glucose as the carbon sources and displayed a doubling time of about 48 h. Comparisons in growth and N2-fixing activity ofFrankia strains grown in a variety of cultural conditions demonstrate the range of behavior among the strains.  相似文献   

18.
A study was undertaken to examine the extent of root colonization by four locally isolated ectomycorrhizal (ECM) fungi (Hebeloma theobrominum, Boletus dryophilus, Scleroderma citrinum and Suillus luteus) and their effects on seedling growth in Pinus wallichiana and Cedrus deodara under nursery conditions. Seedlings of the two conifers were inoculated with mycelium of ECM fungi and were grown in pots containing sterilized forest soil for six months. The percentage of ECM colonization of roots was 38%-52% in Pinus wallichiana and 33%-48~ in Cedrus deodara. ECM colonization increased shoot height, needle number, shoot and root biomass and survival of inoculated seedlings. Among the four ECM fungi Hebeloma theobrominum was more effective with Pinus wallichiana and Scleroderma citrinum with Cedrus deodara in promoting seedling survival and overall growth. All the four ECM fungi used enhanced growth of inoculated seedlings and thus can be used in afforestation and regeneration programmes in degraded forests ecosystems.  相似文献   

19.

Aims

The aim of our study was to clarify whether inoculating a soil with Pseudomonas sp. RU47 (RU47) bacteria would stimulate the enzymatic cleavage of organic P compounds in the rhizosphere and bulk soil, promoting plant growth. Adding either viable or heat treated RU47 cells made it possible to separate direct from indirect effects of the inoculum on P cycling in soil and plants.

Methods

We performed a rhizobox experiment in the greenhouse with tomato plants (Solanum lycopersicum) under low P soil conditions. Three inoculation treatments were conducted, using unselectively grown soil bacteria (bacterial mix), heat treated (HT-RU47) and viable RU47 (RU47) cells, and one not inoculated, optimally P-fertilized treatment. We verified plant growth, nutrient availability, enzyme activities and microbial community structure in soil.

Results

A plant growth promotion effect with improved P uptake was observed in both RU47 treatments. Inoculations of RU47 cells increased microbial phosphatase activity (PA) in the rhizosphere.

Conclusions

Plant growth promotion by RU47 cells is primarily associated with increased microbial PA in soil, while promotion of indigenous Pseudomonads as well as phytohormonal effects appear to be the dominant mechanisms when adding HT-RU47 cells. Thus, using RU47 offers a promising approach for more efficient P fertilization in agriculture.
  相似文献   

20.
固氮菌与溶磷菌接种对红海榄生长的影响   总被引:1,自引:0,他引:1  
李玫  何雪香  廖宝文 《生态科学》2008,27(4):222-226
采用室内盆栽试验,研究固氮菌(Phy)、溶磷菌(Vib)单接种及双接种对红树植物红海榄植株生长和氮、磷营养的影响.接种后6个月对试验苗的生长指标等测定及分析表明,Phy、Vib单接种或Phy+Vib双接种均能改善红海榄氮、磷素营养,增强其光合作用,进而明显促进植株的生长和生物量的增加;其中Phy+Vib双接种的促生效果最显著,其苗高、茎径、地下生物量、总生物量、根全氮含量、根全磷含量和叶片叶绿素总量分别比未接种的对照苗提高43.3%,11.6%,44.8%,29.9%,29.3%,27.0%和16.8%.固氮菌(Phy)、溶磷菌(Vib)双接种在促进红海榄植株生长方面表现出一定的正交互效应,可用于苗期接种.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号