首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 156 毫秒
1.
不同AM菌根菌分泌的磷酸酶对根际土壤有机磷的影响   总被引:18,自引:1,他引:18  
苏友波  林春  张福锁  李晓林 《土壤》2003,35(4):334-338,343
以三叶草为材料,利用3室隔网培养方法,研究了4种AM菌根菌侵染三叶草后对根际土壤酸性和碱性磷酸酶活性以及菌丝酶活性对土壤有机P的影响。结果表明,接种AM菌根菌 (9周) 对根际土壤酸性和碱性磷酸酶活性均有增强作用,但作用强度主要取决于菌丝在土壤中的生长状况,Glomus属菌根菌在整个菌丝室 (0~6cm) 都影响土壤磷酸酶的活性,其活性在整个菌丝室中都比Gigaspora的高。同一属不同种的根际土壤磷酸酶活性差异不大。AM菌根根际土壤磷酸酶对土壤有机P的降解有很强的促进作用。  相似文献   

2.
为了进一步确定微生物复垦对土壤的持续修复能力,在神东矿区活鸡兔开采沉陷试验基地,接种丛枝菌根真菌和大豆根瘤菌改良农用地土壤,已取得了较好的微生物复垦效果,经过2 a的退耕撂荒以后,对微生物复垦后效进行系统地研究。研究结果表明,撂荒后,接菌小区根外菌丝密度、根系侵染率和pH值均显著高于对照小区,分别比对照提高了90%、52%和1.3%;接菌小区细菌数量、微生物总量、有效磷含量、电导率和酸性磷酸酶活性也明显高于对照小区,但差异不显著。撂荒后与撂荒前相比,土壤呈退化趋势,但接菌小区菌丝密度几乎增加了1倍,差异显著,同时侵染率、细菌数量和酸性磷酸酶活性均明显升高,差异不显著;而在对照小区中,菌丝密度稍有增加,侵染率、细菌数量和酸性磷酸酶活性均明显降低,且差异不显著。利用丛枝菌根真菌与大豆根瘤菌联合作为绿色环保肥料,能够有效改善根际土壤环境,减轻土壤的退化程度,在弃耕状态下也能发挥良好的效用,对土地贫瘠的开采沉陷地进行生态修复具有重大意义。  相似文献   

3.
西瓜易受尖孢镰刀菌侵害发生枯萎病。植物形成丛枝菌根(AM)可有效促进养分吸收和病害防控。在田间直接接种丛枝菌根菌时,侵染效率和生态效应多数会受到限制。采用育苗期接种丛枝菌根菌(Rhizophagus intraradices,R.i)培养菌根苗,成苗后移栽入盆钵,研究西瓜丛枝菌根苗在抗西瓜枯萎病中的作用及其机制。将西瓜丛枝菌根苗移栽入大田,研究丛枝菌根西瓜苗在田间防控西瓜枯萎病及改善磷营养的效果。结果表明,苗期形成的丛枝菌根苗,在移栽后上调几丁质酶编码基因ClPR4、ClPR5在根系的表达量,上调b-1,3-葡聚糖酶编码基因ClGlu3和苯丙氨酸解氨酶编码基因ClPAL4、ClPAL11在根系的表达量;西瓜丛枝菌根育苗提高了根际土壤酸性磷酸酶活性,提高土壤有效磷含量,改善磷营养,提高西瓜植株抗枯萎病的能力。同时丛枝菌根育苗提高了西瓜根际土壤中的丛枝菌根菌孢子数,降低了根际土壤中病原菌数量,降低西瓜枯萎病发病率及病情指数。因此,丛枝菌根育苗上调了西瓜植株抗性相关酶基因表达,提高西瓜抗病性;同时提高了根际酸性磷酸酶活性而改善了磷营养,提高植株抗病能力。  相似文献   

4.
采用温室盆栽试验方法,研究了丛枝菌根真菌(AMF)Glomus mosseae和Glomus etunicatum对菲芘复合污染土壤中3种酶活性的影响。宿主植物为三叶草(Trifolium repens L.)和黑麦草(Lolium multiflorum Lam)。土样中菲和芘起始浓度分别为203.4mg·kg^-1和107.5mg·kg^-1。结果表明,植物增加了土壤多酚氧化酶、酸性磷酸酶和过氧化氢酶活性。接种Glomus mosseae和Glomus etunicatum使三叶草根际土壤多酚氧化酶活性20-60d分别增加19.6%-72.0%和29.7%-90.6%,过氧化氢酶活性分别增加3.3%-12.2%和7.8%-34.7%,酸性磷酸酶活性总体呈增加趋势;接种Glomus mosseae使黑麦草根际多酚氧化酶活性增加18.0%-43.1%,过氧化氢酶活性总体上呈降低趋势,酸性磷酸酶活性先升高后降低。供试的两种AMF对三叶草根际酸性磷酸酶和过氧化氢酶活性的影响30d前有显著差异。AM真菌作用的性质与宿主植物特性有关。  相似文献   

5.
试验研究 3种丛枝菌根真菌根内菌丝碱性磷酸酶活性与菌根共生效应的结果表明 ,3种丛枝菌根真菌对宿主植物的效应不同 ,与接种G .spp处理和未接种对照相比 ,接种G .m和G .i处理显著增加玉米地上部和根系干物质量、P浓度和吸P量 ,但后两者间无显著差异 ;而接种G .spp处理与对照无显著差异。播种后 35d时接种G .m和G .i处理根内菌丝碱性磷酸酶活性显著高于接种G .spp处理 ,而前二者间无显著差异 ,且随生长时间的变化趋势相似 ,35d时酶活性最高 ,35~ 5 0d呈迅速下降趋势 ,至 70d时酶活性仍下降且趋于平缓。G .spp酶活性则一直处于较低水平 ,随生长时间的延长略有起伏。即接种不同丛枝菌根真菌时 ,根内菌丝碱性磷酸酶活性高的菌根真菌对玉米生长促进作用较大 ,可提高玉米P营养状况 ;反之则对玉米生长和P营养状况无明显促进作用 ,且与对照无显著差异。出苗后 35d时根内菌丝碱性磷酸酶活性是预测丛枝菌根真菌对玉米生长效应的有效生理指标之一。  相似文献   

6.
不同磷源对作物根际效应影响的研究   总被引:3,自引:1,他引:3  
本文通过网室盆栽和室内分析相结合的方法,研究了几种P源施入石灰性土壤后对作物根际生物活性性质的影响,结果表明:对于不同P源处理,小麦生长过程中根际、非根际微生物种群的数量及根际效应(R/B)有显著差异,其大小顺序为:K2HPO4>CaMg-P>SSP>FA>CK。微生物数量在生育后期达到高峰。作物根际磷酸酶活性随生育期的进展逐步增强。不同P源处理影响下的土壤磷酸酶活性有一定的差异,总体顺序为:FA>SSP >K2HPO4> CaMg-P>CK。土壤碱性磷酸酶活性显著地高于中性磷酸酶活性。  相似文献   

7.
丛枝菌根真菌(AMF)在土壤与植物的磷素循环中发挥着关键的作用。采用盆栽实验研究了丛枝菌根真菌群落对白三叶草植株生物量、磷吸收和土壤磷酸单酯酶活性的影响。结果表明,接种不同AMF群落均能显著地促进白三叶草植株的生长及其对磷素的吸收,提高根际土壤磷酸单酯酶的活性。Mnp处理中,白三叶草生物量最大,白三叶草总生物量、茎叶生物量和根系生物量分别比对照处理(-M)提高64.48%、61.48%和84.91%。不同菌根处理中,Mck处理显著地提高白三叶草磷吸收和土壤磷酸单酯酶活性,白三叶草磷吸收总量和茎叶磷吸收量分别比对照(-M)提高107.18%和91.91%,土壤碱性磷酸单酯酶和酸性磷酸单酯酶活性相对对照(-M)分别提高54.33%和138.43%。碱性磷酸单酯酶活性与AMF群落中的Acaullospora属孢子数呈显著的正相关关系,而酸性磷酸单酯酶活性则主要受Paraglomus属孢子数的影响。说明接种AMF群落可显著地影响土壤的磷酸单酯酶活性,从而影响白三叶草的生长及其对磷素的吸收。  相似文献   

8.
针对辽西北地区干旱缺水、土壤贫瘠、造林成活率低等问题,研究在对樟子松接种外生菌根真菌的基础上施加一定浓度的外源Ca~(2+),目的是研究菌根真菌和Ca~(2+)的互作对樟子松根际微环境改良作用。于生长季节,利用盆栽方法,在种子出苗后人工接种外生菌根菌(ECMF)-褐环乳牛肝菌(Suillus luteus),并施用0 mmol L~(-1)~50 mmol L~(-1) CaCl_2,以不接菌和不加CaCl_2为对照。在苗木生长3个月后,分别测定苗木的菌根侵染率、苗木根际土壤过氧化氢酶等土壤酶活性、根际土壤微生物数量、有效磷含量等土壤指标,评价外源钙和外生菌根菌对樟子松根际土壤的改良作用。结果表明:1)适当浓度的外源Ca~(2+)和外生菌根菌协同能够更好的提高苗木根际土壤酶活性,提高根际土壤养分含量。2)适当浓度的外源Ca~(2+)和外生菌根菌协同能够更好的增加樟子松苗木根际微生物数量,增加根际土壤生物活性。3)适当浓度的外源Ca~(2+)和外生菌根菌协同能够更好的促进樟子松苗木的生长。综上,施加外源钙能够达到改良樟子松苗木的根际土壤,提高土壤生物活性的目的。在苗圃育苗初期或者造林时,在接种外生菌根真菌进行菌根化育苗的同时,施加适当浓度的外源钙来实现改良土壤是可行的。  相似文献   

9.
以磷高效型小麦洛夫林和磷低效型小麦中国春为试材设计三室根箱试验,通过测定两品种小麦生物量、吸磷量、pH值和酸性磷酸酶活性,对比它们在两种磷水平(P 0 mg/kg、P 100 mg/kg)及两种土壤(石灰性黑垆土、酸性红壤)上的根际特征差异。结果表明,黑垆土上增施磷肥,洛夫林和中国春的总生物量分别增加了30.14%和17.75%,总吸磷量分别增加了139.24%和71.72%;红壤上增施磷肥,两小麦总生物量并没有显著增加。根际pH方面,黑垆土上,不施磷条件下,洛夫林和中国春的根际pH值分别降低0.30和0.12个单位,但在红壤上两小麦根际pH值变化不大。酸性磷酸酶方面,PO条件下,黑垆土上两小麦根际酸性磷酸酶活性差异不显著,但红壤上洛夫林酸性磷酸酶活性显著高于中国春。P100条件下,黑垆土上洛夫林酸性磷酸酶活性显著高于中国春,而红壤上两小麦酸性磷酸酶活性差异不大。试验结果表明,在黑垆土和红壤上,两种磷效率小麦根际特征存在差异。  相似文献   

10.
碳酸钙和根际作用对酸性红壤解磷微生物丰度的影响   总被引:3,自引:0,他引:3  
郑曼曼  王超  沈仁芳 《土壤》2020,52(4):704-709
选用玉米品种郑单958为试验材料,设置不添加碳酸钙(CK)、每千克土添加0.3g碳酸钙(Ca-0.3)和0.5g碳酸钙(Ca-0.5)3个碳酸钙处理,以相应处理未种植物土壤为非根际对照土壤,研究了碳酸钙和根际作用对酸性红壤磷酸酶活性及解磷微生物相关功能基因phoC和phoD丰度的影响。结果表明:碳酸钙添加能有效改善玉米生长,促进地上部氮、磷、钾和钙的吸收。土壤酸性磷酸酶(ACP)活性显著高于碱性磷酸酶(ALP)活性,表明酸性土壤中ACP在矿化有机磷方面占主导地位。根际土壤ACP、ALP活性和phoD基因拷贝数均显著高于非根际,而仅Ca-0.5处理ALP活性和phoD基因拷贝数显著高于CK,说明根际效应强于碳酸钙处理。phoC基因拷贝数与土壤铵态氮、硝态氮含量存在显著相关性,ALP活性和phoD基因拷贝数与土壤pH及铵态氮、硝态氮、有效磷、交换性钙含量均存在显著相关性。可见,碳酸钙和根际作用均影响酸性土壤解磷微生物功能和丰度,但根际效应更加明显,这些作用与土壤理化因子的改变密切相关。  相似文献   

11.
VA菌根菌丝对紧实土壤中磷的吸收   总被引:7,自引:0,他引:7  
本文采用三室隔网盆栽试验方法,选择三种土壤容重(1.3;1.6;1.8g/cm3)来模拟自然条件下不同紧实度对植物根系生长的抑制情况,探讨了接种VA菌根真菌Gmosseae对三叶草植株生长和对土壤磷吸收的影响。结果表明随着土壤容重的增加,三叶草根系生长受到抑制的程度随之加重。当土壤容重为1.8g/cm3时,根系基本不能生长,而菌丝却能在其中伸展并吸收养分。表现为1.8土壤容重的处理菌根植物的含磷量明显高于无菌根植物。而在低容重的处理中两者却没有显著差异。说明VA菌根真菌能缓解甚至消除土壤机械阻力对植物生长的胁迫。  相似文献   

12.
A greenhouse experiment was conducted to examine the favorable effects of sod culture system with bahiagrass (Paspalum notatum Flügge.) and Vulpia myuros (L.) C. C. Gmel. intercropped with citrus trees on the establishment of the network of arbuscular mycorrhizal (AM) fungus hyphae in their rhizospheres. Special acrylic root boxes with three compartments were used for the experiment. Four types of citrus rootstock seedlings, trifoliate orange (Poncirus trifoliata Raf.), sour orange (Citrus aurantium L.), rough lemon (Citrus jambhiri Lush.), and Citrus natsudaidai Hayata, were separately transplanted into one outer compartment in each box, and the seedlings of bahiagrass and V.myuros were separately transplanted into the other outer compartment. An AM fungus, Gigaspora margarita Becker and Hall, was inoculated in the center compartment of each box. Some boxes with both outer compartments without plants and with some plants in only one outer compartment were also prepared. The box with bare × bare had very low density of AM hyphae. There were a few hyphae in bare compartments in the boxes of trifoliate orange × bare, sour orange × bare, rough lemon × bare, and C. natsudaidai × bare. The density of hyphae in the compartments with citrus seedlings and grasses, however, was significantly higher than in every bare compartment, and the hyphae in the compartments with plants penetrated deeply into the sand. In particular, the density in the compartments of citrus seedlings increased when bahiagrass or V. myuros was transplanted as a neighboring plant. The percentage of AM fungus colonization in every plant root was high. New spore formation was observed in compartments with plants, whereas there were few spores in every bare compartment. In particular, the spore formation in bahiagrass compartments was superior to that in other compartments with plants. Our results suggest that the network system by AM hyphae is easily discernible in the rhizospheres between citrus rootstocks and bahiagrass or V. myuros, but bare ground severely inhibits the formation and development of AM hyphal network and reduces the number of AM spores in the soil.  相似文献   

13.
An alkaline phosphatase in the intraradical hyphae of arbuscular mycorrhizal fungi was found to be closely related to an improvement of plant growth. To detect the phosphatase activity in a crude extract of mycorrhizal roots, phosphatase isozymes in mycorrhizal and non-mycorrhizal onion roots were compared with those in Gigaspora margarita by electrophoresis. A mycorrhiza-specific band was found when the phosphatase was stained under alkaline conditions. To clarify the origin of this phosphatase, the phosphatase extracted from intraradical hyphae was also compared with the phosphatase from mycorrhizal roots by electrophoresis. The intraradical hyphae was isolated from mycorrhizal roots by enzyme digestion followed by Percoll gradient centrifugation. The soluble protein was extracted from the hyphae by ultra-sonication after treatment with chitinase. A phosphatase in the hyphal soluble protein showed a similar, but slightly higher, relative mobility on the gel, compared with the mycorrhiza-specific phosphatase from roots. By adding the hyphal extract to the root extract, the relative mobility of the mycorrhiza-specific phosphatase was slightly changed and became identical to that of the phosphatase in the hyphae. This indicated that the specific band of phosphatase found in the crude extract from mycorrhizal roots was of intraradical hyphal origin. Received: 16 April 1997  相似文献   

14.
A rhizobox experiment was conducted to investigate the effects of phosphorus (P) sources on the rhizosphere soil characteristics of two wheat genotypes Xiaoyan54 (P-efficient) and Jing411 (P-inefficient), which were colonized with an arbuscular mycorrhizal fungus and grown in Cumulic Haplustoll. The four P sources included a control (no added P), OP [organic P: sodium (Na)-phytate], IP [inorganic P: monopotassium phosphate (KH2PO4)], and OPIP (Na-phytate plus KH2PO4). The results showed that when no exogenous P was added the shoot biomass of Xiaoyan54 was 28% significantly higher than Jing 411. The acid phosphatase activity (APA) in the rhizosphere soil was significantly depressed when inorganic P was added; the APA for Xiaoyan54 was higher than that of Jing411 in most of the layers regardless of the P source. Inorganic and organic P fertilizer conditions did not significantly impact the soil pH relative to the control, and the pH did not significantly differ between the two genotypes. In conclusion, when no exogenous P was added, shoot biomass of Xiaoyan54 was greater than Jing411. This increase was promoted by greater soil APA but not soil acidification. The rhizosphere soil pH was not altered across different wheat genotypes or P sources, but APA was increased in the soil of control and OP-treated plants compared with IP- and OPIP-treated plants. The APA of Xiaoyan54 was higher than Jing411 for all of the P sources. The response mechanism of rhizosphere soil acidification is different from acid phosphatase exudation in plants receiving different P sources under arbuscular mycorrhizal fungus inoculation.  相似文献   

15.
A simple method is described for trapping phosphate solubilizing bacteria (PSB) strongly attached to the hyphae of the arbuscular mycorrhizal fungus (AMF) Rhizophagus irregularis (Ri). Bacteria were isolated from the hyphosphere of mycorrhizal leek plants growing on Turface previously inoculated with soil suspensions, obtained from the mycorrhizosphere of mycorrhizal plants growing in agricultural settings or maple forests in Quebec, Canada. Among the best PSB strongly attached to the hyphae of Ri, 26 isolates belonged to Burkholderia spp. and one was identified as Rhizobium miluonense. Four hyphobacteria exhibiting high potential of inorganic and organic P mobilization were further compared with four equivalent mycorrhizobacteria directly isolated from mycorrhizospheric soils sampled. In general, hyphobacteria were superior in mobilizing P from hydroxyapatite and from a low reactivity igneous phosphate rock from Quebec. Release of gluconic acid or the product of its oxidation 2-ketogluconic acid, are the main mechanisms involved in P solubilization. In a two compartments Petri plate system, Ri extraradical hyphal exudates, supported PSB growth and activity. In the absence of PSB Ri showed a negligible P solubilization activity. In the presence of PSB a substantial increase in P mobilization was observed, and the superiority of hyphobacterial activity was also observed under this system. Our results suggest that in developing a bioinoculant based on selected PSB, their interaction with AMF hyphae should not be overlooked.  相似文献   

16.
The organic matter supply can promote the dispersal and activity of applied plant growth–promoting rhizobacteria (PGPR), but the complementary effect of organic fertilization and PGPR application on the turnover of P is scarcely known. The effects of the application of two PGPR strains (Pseudomonas fluorescens strain DR54 and Enterobacter radicincitans sp. nov. strain DSM 16656) alone and in combination with organic fertilization (cattle manure and biowaste compost) on growth and P uptake of maize (Zea mays L.) and oilseed rape (Brassica napus L.) were investigated under semi–field conditions. Furthermore, P pools and phosphatase activities in soil and the arbuscular mycorrhizal colonization of maize were examined. The organic‐fertilizer amendments increased the growth and P uptake of both plant species and the soil P pools. The application of the E. radicincitans strain increased P uptake of oilseed rape when no organic fertilizer was added. Furthermore, the application of both bacterial strains increased the activities of phosphatases under both plant species. Here, the effect of the PGPR application even exceeded the effect of organic fertilization. The magnitude of this effect varied between the different fertilizing treatments and between the two bacterial strains. Phosphatase activities were increased to the greatest extent after application of P. fluorescens in the unfertilized soil. Under rape increases of 52% for acid phosphatase activities (ACP), 103% for alkaline phosphatase activities (ALP), and 133% for phosphodiesterase (PDE) were observed therewith. In the unfertilized soil, the application of P. fluorescens also resulted in a strong increase of the arbuscular mycorrhizal colonization of maize. We conclude that application of PGPR can promote the P mobilization and supply of crops in P‐deficient soils, however, in combination with organic fertilization these effects might be masked by a general improved P supply of the crops. Interactive effects of applied bacterial strains and organic fertilization depend on the sort of organic fertilizer and crop species used.  相似文献   

17.
丛枝菌根真菌对红三叶草利用不同有机磷源的研究   总被引:5,自引:3,他引:5  
以红三叶草为材料 ,利用三室隔网培养方法 ,施用不同有机磷源 :植酸钠 (Na -Phytate)、核糖核酸 (RNA)和卵磷脂 (Lecithin) ,研究接种菌根真菌Glmous versiforme对土壤及外加有机磷源的利用效率 ,另设无机磷及不施磷作为对照。结果表明 ,接种菌根真菌能明显增加植株干物重、含磷量和吸磷总量。与各有机磷处理相比 ,无机磷处理前期的生长效应较好 ,施用有机磷各处理在不同生长时期均明显促进了植株生长 ,但不同有机磷源之间没有显著差异。在植株吸磷量上 ,植株生长 7周以前 ,磷酸二氢钾处理高于其它处理 ,而植株生长 10周时 ,植酸钠处理高于磷酸二氢钾处理。接种菌根处理由于丛枝菌根活化了土壤有机磷 ,到植株生长 10周时其吸收有机磷的量已占吸磷总量的 76 .7%。  相似文献   

18.
The interactions between soil P availability and mycorrhizal fungi could potentially impact the activity of soil microorganisms and enzymes involved in nutrient turnover and cycling, and subsequent plant growth. However, much remains to be known of the possible interactions among phosphorus availability and mycorrhizal fungi in the rhizosphere of berseem clover (Trifolium alexandrinum L.) grown in calcareous soils deficient in available P. The primary purpose of this study was to look at the interaction between P availability and an arbuscular mycorrhizal (AM) fungus (Glomus intraradices) on the growth of berseem clover and on soil microbial activity associated with plant growth. Berseem clover was grown in P unfertilized soil (−P) and P fertilized soil (+P), inoculated (+M) and non-inoculated (−M) with the mycorrhizal fungus for 70 days under greenhouse conditions. We found an increased biomass production of shoot and root for AM fungus-inoculated berseem relative to uninoculated berseem grown at low P levels. AM fungus inoculation led to an improvement of P and N uptake. Soil respiration (SR) responded positively to P addition, but negatively to AM fungus inoculation, suggesting that P limitation may be responsible for stimulating effects on microbial activity by P fertilization. Results showed decreases in microbial respiration and biomass C in mycorrhizal treatments, implying that reduced availability of C may account for the suppressive effects of AM fungus inoculation on microbial activity. However, both AM fungus inoculation and P fertilization affected neither substrate-induced respiration (SIR) nor microbial metabolic quotients (qCO2). So, both P and C availability may concurrently limit the microbial activity in these calcareous P-fixing soils. On the contrary, the activities of alkaline phosphatase (ALP) and acid phosphatase (ACP) enzymes responded negatively to P addition, but positively to AM fungus inoculation, indicating that AM fungus may only contribute to plant P nutrition without a significant contribution from the total microbial activity in the rhizosphere. Therefore, the contrasting effects of P and AM fungus on the soil microbial activity and biomass C and enzymes may have a positive or negative feedback to C dynamics and decomposition, and subsequently to nutrient cycling in these calcareous soils. In conclusion, soil microbial activity depended on the addition of P and/or the presence of AM fungus, which could affect either P or C availability.  相似文献   

19.
A semi-hydroponic culture was used to compare growth and cation nutrition of mycorrhizal (Paxillus involutus) and non-mycorrhizal Scots pine seedlings. When roots and hyphae grew together, concentrations and contents of macronutrients in needles and roots were not significantly different between mycorrhizal and non-mycorrhizal plants. When grown in two separate compartments, root potassium (K) concentrations, concentrations and contents of calcium (Ca) in needles and roots, needle nitrogen (N) concentrations, total N content and contents of root K and Mg were significantly reduced in mycorrhizal plants. Whereas 15N abundance increased in roots of mycorrhizal plants. The results indicated that the extraradical mycelium of the fungus strain used was able to transport N to the plant but did not contribute to long-term cation uptake and growth of host plants. An insufficient supply of macro-elements [N, phosphorus (P)] may account for the reduced growth of mycorrhizal plants and the differences in cation uptake between mycorrhizal and non-mycorrhizal plants.  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