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1.
马占相思扦插繁殖技术研究   总被引:4,自引:0,他引:4       下载免费PDF全文
Effects of substrates, type of auxin, treatment concentration and time on rooting ability of Acacia mangium were systematically studied, and the change trend of rooting ability over time were analyzed. The results obtained from the experiment indicated that the substrate of yellow subsoil could improve the rooting rate of the cuttings significantly. IBA was superior to other auxins in increase the number of mean roots and the longest root length. And general rooting effect for different treatments was evaluated based on subordinate function values analysis. The optimized combinations were the cutting treated by IBA 400 mg·L-1 soaked for 2 hours. Callus were occurred in 5 d after cutting, and higher rooting period occurred in 10—15 d and 25—30 d after cutting.  相似文献   

2.
‘Zhongqiusucui’ jujube secondary shoots were treated with 3-indolebutyric acid(IBA) at three concentrations, 500, 1000 and 1500 mg/L. Results show that IBA could significantly enhance rooting and root characteristics of cuttings and were best with IBA at 1500 mg/L. In the rooting process, the formation of adventitious roots was related to the consumption and accumulation of nutrients(soluble sugars and proteins) and the changes in endogenous hormones in phloem, leaf tips and leaf bases. The rooting of cuttings had a positive correlation with the consumption of soluble sugars during the period of callus formation and with the accumulation of soluble sugars during adventitious root formation and growth. Rooting was positively related to the breakdown of soluble proteins in the phloem when the callus formed, and had a positive correlation with its accumulation during adventitious root formation and growth. Leaf tips and leaf bases showed a reverse trend in changes of soluble protein. However, together with the phloem, leaf tips and leaf bases regulated and controlled the formation and development of adventitious roots. The main activities of soluble proteins exist in the leaf tips as this was the main source of soluble proteins. The relation between rooting and IAA(indole-3-acetic acid) content in phloem was positive and thus a high concentration of IAA could benefit the induction and formation of adventitious roots. However, rooting was negatively related with ABA(abscisic acid) and GA(gibberellic acid) and a high concentration of both could inhibit the induction and formation of adventitious roots. Rooting had a positive correlation with phloem IAA/ABA ratios, and higher ratios could improve rooting. Low concentrations of ZR(zeatin riboside) triggered the induction of adventitious roots, while higher concentrations promoted root growth.Endogenous hormones in leaf tips and bases had an impact on rooting. The activities of endogenous hormones mainly existed in leaf tips because they play a major role in the production and consumption of IAA and its ABA content increased during rooting. The ZR in leaf tips influenced the rooting of cuttings, especially in the callus formation and rooting stage. Leaf tips were the main source of GA.  相似文献   

3.
The tissue-cultured seedlings of tree peony ‘Wulong Pengsheng’ were used to study the effects of different plant growth regulators, culture methods, and holdfast on rooting. The morphological structure change during rooting was also observed using the method of paraffin section. The result showed that the best combination of plant growth regulators for rooting was IBA 3.0 mg·L-1 + NAA 0.6 mg·L-1. The treatment under the temperature of 4℃ for ten days was benefit to rooting, and the rate could reach 75.67%. It was identified that the adventitious root primordia of shoot in vitro originated from the vascular cambium cells, especially, the cross areas of cambium and pith ray and they started to differentiate at the 5th day and lasted to the 12th day. If the shoots were cultured in the root inducing medium for 12 days, it would lead to not only descend of rooting rate, but also showing callus of stem base, and leaf senescent. However, if they were transferred into the medium without hormone in time, the root primordial protruded the epidermis and developed normally after 5 days’ culture.  相似文献   

4.
The region of West and Central Africa is endowed with high-value fruit trees and medicinal plants, which are currently traded locally as well as on regional and international markets. Unfortunately, they are all exploited from the wild and there has been little or no focussed effort to domesticate and cultivate them. Prunus africana is one of these important medicinal plant under domestication. A series of nursery experiments were conducted to assess the effects of rooting medium (sawdust, sand and a 50:50 mixture of sand and sawdust), auxin concentration (0, 50, 100, 150, and 200 μg IBA), and leaf area (0, 5, 10, 20, and 25 cm2) on rooting success of juvenile cuttings of P. africana. The percentage of cuttings rooted was significantly greater (P < 0.05) in sawdust (80%), than in sand alone (72%) or in mixture with sawdust (71%). Leaf area also significantly affected the percentage of rooting. Leafless cuttings did not root and were all dead by week 6, but in leafy cuttings rooting ability increased proportionally with leaf area up to 20 cm2 (79%). Larger leaf cuttings (25 cm2) rooted at the same level as those of 20 cm2. The cuttings with the largest leaves also had the greatest mean number of roots per cutting (14 roots cutting−1), while those with the smallest (5 cm2) leaf area produced the fewest roots (5 roots cutting−1). The application of auxin (IBA) promoted rooting (P < 0.05) up to an optimum application of 100–200 μg IBA per cutting, but 300 μg was supraoptimal. It can be concluded that P. africana is amenable to vegetative propagation. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

5.
4种山茶花营养成分及有害元素含量分析   总被引:2,自引:0,他引:2       下载免费PDF全文
The nutritional components and poisonous elements in flowers of Camellia chekiangoleosa, C. polydonta, C. semiserrata and C. azalea were studied. The results indicated that the soluble sugar content of the four Camellia flowers had no difference. The maximum protein content was 82.9 g·kg-1, detected in the flower of C. semiserrata. And the minimum protein content was 56.8 g·kg-1, found in C. azalea. Vitamin C and β-carotene contents in C. azalea and C. semiserrata were higher, and in C. polydonta and C. chekiangoleosa were lower. The total amino acid contents of the four Camellia were 68.41、67.26、50.77、66.87 g·kg-1 respectively, the essential amino acid contents were 33.86、32.70、27.21、33.79 g·kg-1 respectively, and the proportion of essential amino acid in total amino acid of the four Camellia were 49.50%, 48.62%, 53.59% and 50.53% respectively. The contents of Ca, Mn and Cu in C. chekiangoleosa were the highest. Zn and Se contents were the maximum and Ca was the minimum in C. polydonta. The contents of Fe and Se were the lowest in C. semiserrata. Fe content were the maximum and Mn, Zn and Cu the minimum in C. azalea. The trace element contents in the flower of the four Camellia species followed the order of Mn, Fe, Zn, Cu, Se, but the content of Fe was higher than that of Mn in C. azalea. The contents of Pb, Cd, As and Hg of the four Camellia flower were all lower than the permissible amount.  相似文献   

6.
Glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) was purified from the leaves of 8-week-old Populus suaveolens cuttings. The enzyme activity in the absence and presence of reduced dithiothreitol (DTTred) was determined. The results show that the G6PDH activity is not inactivated by pre-incubation with DTTred, indicating that the purified enzyme probably presented in cytosol of P. suaveolens. The catalytic characteristics and kinetic parameters of cytosolic G6PDH purified from P. suaveolens cuttings were also studied. The results show that G6PDH is characterized by K m value of 360 μmol·L−1 for G6P and 16 μmol·L−1 for NADP, a pH range of 7.3-8.9, and the maximum activity around pH 8.2. The enzyme activity is inhibited by various metabolites such as NADPH, NADH, GTP, UTP, ATP, AMP, ADP, CoA, acetyl CoA, fructose-6-phosphate (F6P), erythrose-4-phosphate (E4P), ribose-5-phosphate (R5P) and 3-phosphoglycerate (3-PG) (all at 1 mmol·L−1 except for NADPH and NADH) to different extents. NADPH is the most effective inhibitor of enzyme activity, with an inhibition of 72.0%. The addition of metal ions such as MgCl2, CaCl2 and KCl (all 1.0 mmol·L−1) to the standard reaction mixture has no remarkable influence on the cytosolic G6PDH activity. However, CdCl2 (1.0 mmol·L−1) causes high inhibitory effect on the enzyme activity. To explore the role of G6PDH on the enhancement of freezing resistance induced by freezing acclimation, the changes in the cytosolic G6PDH activity and freezing resistance (expressed as LT50) of P. suaveolens cuttings during freezing acclimation at −20 °C were investigated. The results reveal that freezing acclimation decreases LT50 of cuttings, and increases the activity of cytosolic G6PDH compared with control ones, while 2 d of de-acclimation at 25 °C result in a decrease in cytosolic G6PDH activity, and caused an increase in LT50. Furthermore, the change in cytosolic G6PDH activity is found to be closely correlated to the degree of freezing resistance of cuttings during freezing acclimation. It is suggested that cytosolic G6PDH may be involved in the induction of freezing resistance of cuttings. [Supported by the Foundation of State-designated Base for Biology Researching and Teaching in Beijing Forestry University]  相似文献   

7.
郁金香授粉后雌蕊生理生化变化的初步研究   总被引:1,自引:0,他引:1       下载免费PDF全文
The protective enzyme (SOD, POD, CAT) activities and soluble protein content of pistil after pollination were compared between interspecific-cross and self-cross of cultivar, using Tulipa specie (T. tianschanica) from Xinjiang and T. gesneriana cultivars ('Kees Nelis’, 'Negrita’) as test materials. The results showed that all the SOD, POD, CAT activities and soluble protein content changed after interspecific and self pollination, which means that the recognition between pollen and stigma can be initiated effectively when pollen fell on stigma despite of genetic relationship. Fluctuant changes were observed in 5 hours after pollination for protective enzyme activities and soluble protein content, and the fluctuation tendencies were different between interspecific and self pollination, as well as between 'Kees Nelis’ ×T. tianschanica and 'Negrita’×T. tianschanica. Self pollination appeared peaks of POD and CAT activities preceding interspecific pollination. Self pollination showed a larger rise and maintained rise for longer time than interspecific pollination. The SOD activity of 'Kees Nelis’ ×T. tianschanica changed more than that of 'Negrita’×T. tianschanica, meanwhile, the soluble protein content of the former declined preceding that of the latter. These differences were probably attributed to genetic relationship.  相似文献   

8.
不同基质配方对金叶榆容器苗质量的影响   总被引:12,自引:1,他引:12       下载免费PDF全文
Through Ulmus pumila cv. 'Jinye’ container-growing seedling cultivation experiment with 4 types of media or 9 media formulas, the seedling height, the stem and crown diameter indexes of U. pumila cv. jinye were measured. These indexes were significantly or extreme significantly different among various media. The growth of seedling root system varied with different media. The rooting and root number in soft media were much better than that in dense media. According to the growth traits of above-ground and underground parts of U. pumila cv. jinye seedlings, the medium suitable for U. pumila cv. jinye seedling growth was defined as media type I, whose ratio of C/N was 17.7—18.1, the density was higher than 0.26 g·cm-3. Grown on this medium, the height, stem diameter and crown diameter of U. pumila cv. jiny were 1.34—1.57 m, 1.36—1.50 cm and 59.6—73.9 cm, respectively. The results of experiment showed also that the physical property played an active role in cultural media, so a good initial medium could provide great assistance of fertilization and water management in seedling culture.  相似文献   

9.
The effect of auxins (IAA or IBA at 100,200,500 mg L 1) on rooting and sprouting parameters differed significantly (p < 0.05).Rooting and sprouting percentages were higher in some treatments while other parameters were significantly higher in other treatments.The results of the present study revealed that rooting was significantly (p < 0.05) affected by the length of cuttings,as well as the position of shoots and type of cuttings.On average,86.0 per cent rooting was observed in the 30-cm long cuttings compared to the other two lengths of cuttings,i.e.,20 and 25 cm,irrespective of any auxin treatment.In a control set,without any auxin treatment,a maximum of 60.0% rooting was recorded in the 30-cm long cuttings and a minimum of 40.0% of the cuttings rooted in the 20-cm long cuttings.Similarly,cuttings collected from the lower and upper portions of shoots resulted in 72.5 and 52.5 per cent rooting respectively,irrespective of auxin treatments.Maximum rooting was observed in the lower portion (40.0%) of cutting compared to the upper portion (30.0%) in the control set without auxin treatment.Leafless branches produced maximum (72.0%) rooting compared to the leafy cuttings (35.0%),irrespective of the auxin treatment.The leafy cuttings produces a minimum of 15.0% sprouting and rooting in the control set.  相似文献   

10.
不同品种油茶嫁接苗根系生长动态研究   总被引:5,自引:1,他引:5       下载免费PDF全文
The growth dynamics of root system and aboveground of the grafted seedlings of different Camellia oleifera cultivars are studied by skeleton method and root scanning. The results of 8-months’ observation on grafted seedlings of 5 C. oleifera cultivars showed that: the growth of aerial parts and root of the C. oleifera seedlings were not entirely in sync, during the time of low temperature from November to February, the root system still in sustained growth though the aerial parts of the 5 cultivars grew slowly. Remarkable differences were existed in root length, root surface area, root volume, root biomass and other indicators after 11-months’ growth. The mean value of total length of root-system was up to 243.3 cm and 143.4 cm for the minimum, the mean value of total root surface area was up to 50.2 cm2 and 31.7 cm2 for the minimum, the mean value of root volume of the C. oleifera seedlings was up to 0.843 cm3 and 0.578 cm3 for the minimum which lived 11 months after grafting. All the root length, root surface area, root volume of the 5 cultivars have remarkable differences.  相似文献   

11.
杂种落叶松连续繁殖与插穗生根关系的生理研究   总被引:1,自引:0,他引:1       下载免费PDF全文
观察了日×长杂种落叶松连续繁殖插穗不定根发育进程,研究了连续繁殖对插穗生根力衰退的阻滞效应,并分析了一轮采穗圃与原株采穗圃插穗不定根发育期内源激素含量的动态变化。结果表明:扦插后13 31 d是愈伤组织形成和不定根原始体分化发育的关键期,此时一轮分生株愈伤组织形成和不定根发育均优于原株。连续繁殖对插穗生根性状有显著作用,尤其是生根率很低的原株,经过一轮繁殖后,生根性状有极显著提高。连续繁殖影响插穗自身激素含量,尤其是IAA,经过一轮繁殖后,含量明显高于原株。从不定根发育过程中激素的动态变化看,一轮分生株插穗(IAA+GA3+ZR)/ABA比值在不定根发育前期明显高于原株,与生根率的变化一致,可用来衡量不同繁殖次数插穗生根性状的优劣。  相似文献   

12.
西南桦(Betula alnoides Buch.-Ham.ex D.Don)是我国西南省(区)造林规模最大的乡土珍贵用材树种.西南桦具有材性优良、容易加工、色泽淡红、不易变形等木材特性,是高级家具、室内装修、木地板的优质材料,经济价值甚高.由于目前育苗用种多采自天然次生林,随着西南桦天然资源的日益贫乏,加剧了造林规模不断扩大与供种量逐渐减少的矛盾;而且,实生苗造林的林木个体间遗传变异较大,林分木材单产较低.随着良种选育工作的深入,西南桦人工林向"有性选育,无性利用"路径发展.  相似文献   

13.
In order to study and monitor rates of rooting, callusing and survival, small diameter stem cuttings (less than 0.4 cm) with eight nodes (12–14 cm long) were taken from trees in the field at different times of the year in tests with small batches of cuttings. Among the four tested substrates, well drained crushed basalt powder placed on a bed of gravel was the best rooting medium. Rooting was generally poor or even non-existent with this type of cutting, but the presence of leaves both promoted rooting and significantly (using Chi square test) improved survival of the cutting. Four leaves were sufficient to assure the necessary metabolic functions. Only stem cuttings collected during the rainy season gave roots and then, only when hormonal treatments were applied to the cuttings. 8%-IBA resulted in significantly better rooting than did 2%-IBA, 0.2%-NAA and 1%-IAA. With 8%-IBA, the rate of rooting varied between 50 and 70% for leafy cuttings collected in the rainy season. Hormonal treatments had a significant effect on the survival rate of the stem cuttings during the two months observation period. Further investigations are being conducted with different types of cuttings.  相似文献   

14.
蓝云杉不同品种扦插生根能力和生根特性研究   总被引:4,自引:1,他引:3       下载免费PDF全文
在甘肃小陇山林业科学研究所苗圃,系统研究了IBA、NAA、ABT对不同蓝云杉品种的扦插生根能力.研究结果表明:蓝云杉插穗愈伤始期为扦插后10 d,插后30d开始生根,高峰期在插后40~70 d,80d时扦插生根率达到97%.蓝云杉5个品种间扦插生根率和平均根长差异显著,品种间生根数量存在极显著的差异.插穗处理时间是影响...  相似文献   

15.
Applied auxin, node position, leaf area and cutting length were examined to investigate the requirements for rooting stem cuttings of Khaya ivorensis. All these variables were shown to be important factors affecting rooting, confirming the hypothesis that successful rooting can be achieved if these primary variables are optimised.The best concentration of the auxin IBA was found to be 200 g per cutting, which hastened rooting, increased the percentage of cuttings rooted and increased the number of roots per cutting. One clone (8013) was unresponsive to auxins in terms of the percentage of cuttings rooted, but was the most responsive in terms of the numbers of roots per cutting. A greater percentage of cuttings from basal nodes were rooted than from apical nodes. Cuttings cut squarely at the base produced a radially-arranged root system, whereas an oblique cut resulted in a one-sided root system.Trimming the leaf area of cuttings to 10 cm2 gave greater rooting percentages than trimming to 100 cm2. In general, long cuttings (39 mm) rooted better than short cuttings (19 mm), however, there was an interaction between leaf area and cutting length, in which cuttings with short stems and large leaves had the lowest rooting percentage.  相似文献   

16.
比较不同基质、不同生根促进剂及其质量体积浓度、不同季节、不同修剪方式、不同插穗类 型对钟花樱(Cerasus campanulata)扦插生根的影响,结果表明:扦插基质类型、生根激素种类及其质量 体积浓度、扦插季节、插穗留叶面积以及插穗类型均对钟花樱扦插成活率和生根率产生显著或极显著影 响,扦插基质采用黄心土最有利于生根;生根激素种类及其各浓度处理效果均显著高于清水对照,其中 采用IBA 以质量体积浓度2 500 mg · L-1 速蘸10 s 处理效果最佳;于春季扦插最好;插穗留1 片或半片叶 片成活率及生根率远高于不留叶插穗;采用嫩枝扦插和带踵扦插优于硬枝扦插。因此钟花樱扦插宜在春 季,采用修剪成1 片或半片叶片带踵或嫩枝的插穗,经质量体积浓度2 500 mg · L-1 的 IBA 药液蘸10 s 后 扦插在黄心土上,生根效果最好。  相似文献   

17.
中国特有濒危植物崖柏扦插繁殖研究   总被引:3,自引:1,他引:3       下载免费PDF全文
在重庆市城口县咸宜乡苗圃和中国林科院温室开展崖柏扦插繁殖试验,研究采穗母树年龄、不同激素种类及其组合、激素浓度、扦插基质、物理促根等不同处理方式下崖柏扦插生根效应.结果表明:(1)在咸宜乡苗圃,采用自动喷雾设施,以蛭石-泥炭土-珍珠岩(1∶1∶1)为扦插基质,用3种激素和清水处理崖柏幼树1年生枝条,扦插后160d的生根率为74.76%~96.70%,不同处理组合生根效应具有显著差异,2000 mg· L-1 IBA>清水对照(CK)>1 000mg·L-1 IBA>1 000 mg·L-1IBA+ 500 mg· L-1NAA;(2)在林科院温室用2种激素和清水处理崖柏幼树1年生枝条,扦插于蛭石-泥炭土-珍珠岩(1∶1∶1)的基质,搭塑料拱棚,扦插后120 d的生根率远低于咸宜乡苗圃,为25.93%~45.37%,激素处理后的枝条与对照差异显著,1 000 mg·L-1 IBA+ 50 mg·L-1 NAA=2 000 mg·L-1 IBA>清水对照(CK);(3)在咸宜乡苗圃用不同激素和物理促生根方法组成的27种组合处理的成年崖柏枝条,最高生根率仅为20.83%.生根率超过10%的处理组合是:清水处理,泥炭土∶蛭石∶珍珠岩(1∶1∶1);1 000 mg·L-1IBA+500 mg·L-NAA,泥炭土∶珍珠岩(2∶1);1 000 mg·L-1IBA,泥炭土∶蛭石∶珍珠岩(1∶1∶1),流水冲洗.  相似文献   

18.
Aging of the donor tree decreased adventitious root formation in shoot cuttings of Tectona grandis Linn. f. (teak). Exogenous application of auxins, i.e., α-naphthalene acetic acid (NAA) and indole-3-butyric acid (IBA) has a significant positive effect on the percentage of rooting. The maximum percent rooting was obtained with 4,000 ppm IBA as compared to other treatment. Significant increase in root number was recorded in shoot cuttings treated with 4,000 ppm NAA. The overall rooting response was better in the treatment with IBA rather than with NAA. Further periodic samples (0, 10, 20, and 30 days) were taken to assess the total soluble sugar, starch, protein, and peroxidase (PER) activity in the rooting zone of shoot cuttings of teak during adventitious root formation. Application NAA and IBA to shoot cuttings resulted in an increase in the level of total soluble sugar, starch, protein, and PER-activity in the rooting zone. The stored carbohydrates were utilized during adventitious root formation. Hence, total soluble sugar and starch contents of cuttings, irrespective of age of donor plants, decreased with the passage of time in cuttings planted for rooting. Significant fluctuations were observed in the protein content of cuttings during the time of root induction. There was an increase in the protein content with the passage of time from the day of planting up to its 20th day, followed by a sharp decline in the protein content of cuttings at the 30th day of planting, irrespective of the age of donor plants or the treatment of cuttings with auxins. Irrespective of donor plant age, PER-activity in the cuttings increased from the day of their planting for rooting up to the 20th day, and then declined at its 30th day of planting. It was interesting to note that PER-activity remained higher at all stages in the cuttings of 2-month-old seedlings which rooted profusely as compared to the cuttings of 15- and 30-year-old donor plants those rooted poorly. This study suggested that the exogenously applied NAA and IBA at different concentration seems to activate sugar metabolism for release of energy, protein and PER-activity which are necessary for cellular division and differentiation during adventitious root primordium initiation or development in the rooting zone of shoot cuttings.  相似文献   

19.
Seedlings of Pinus sylvestris L. were grown at three different irradiances (12, 30, or 60 W m(-2)) under a 17 h photoperiod. After six weeks, cuttings were excised and rooted at 30 W m(-2). Gibberellic acid (GA(3), 5 microl of 2 x 10(-4) or 2 x 10(-3) M) was applied to each cutting immediately after excision. Cuttings from stock plants grown at the low irradiance rooted most quickly, whereas the highest number of roots per cutting was obtained in cuttings from stock plants grown at 30 W m(-2). Gibberellic acid delayed rooting and reduced the number of roots in cuttings from stock plants grown at 12, 30, or 60 W m(-2). The initial carbohydrate content of cuttings increased with stock plant irradiance. For all carbohydrates, except myoinositol and an unknown inositol derivative, the content per cutting increased during the first 28 days of rooting. The GA(3) treatment significantly reduced the starch content of cuttings during the rooting period, but did not significantly change the content of ethanol soluble carbohydrates.  相似文献   

20.
A study was conducted on the twelve clones of shisham (Dalbergia sissoo Roxb.). These clones were obtained from India and Nepal. Single-node leafy cuttings were prepared from the vegetative multiplication garden to examine the clonal variation, effect of IBA treatment on rooting response and associated metabolic changes during adventitious root formation. A remarkable and significant variation was observed due to treatment of 2,000 ppm IBA in the rooting parameters. Clonal variations were also significant for root and shoot growth while length of root was insignificant. Among the twelve clones studied; C3 (Tulsipur, Gonda, Uttar Pradesh, India) and C4 (Laxmipur, Gonda, Uttar Pradesh, India) clone cuttings have given the highest rooting response. Interaction (clone × IBA) was significant only for production of number of roots per cutting. Periodic sampling for clone C3 was performed at 0, 7, 14, 21, 28 and 35 days to examine the contents of total soluble sugars, starch, protein and peroxidase (PER) activity in the rooting zone of cuttings (∼0.5 cm) during adventitious root primordium development. A significant increase in all the metabolic activities was noted due to IBA. Total soluble sugars and starch contents of cuttings decreased with the passage of time. Protein content and PER-activity started to increase in the early stage and reached the highest level on day 21, followed by a decline at the 35th day of sampling. These trends were common for both IBA treated and untreated cuttings. Protein content and PER-activity remained higher in the rooting zone of IBA treated cuttings. Overall these findings suggested that exogenous application of IBA may have activated carbohydrate metabolism for release of energy, while protein and PER-activity were necessary for cell division and differentiation during adventitious root primordium initiation and development in the rooting zone of cuttings.  相似文献   

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