马晓丽等
摘要:通过选择培养基,从红花根际土中分离出8株溶磷效果好的解磷细菌。钼锑抗比色法测量其溶磷能力,通过形态学、生理生化表型测定,结合16S rDNA基因序列同源性分析鉴定,并对获得的溶磷效果较好的菌株进行盆栽试验。试验结果表明:8株菌分为以下几个属,CM1 和 CM6属于假单胞菌属(Pseudomonas),CM4、CM7、CM8属于芽孢杆菌属(Bacillus),CM2、CM3、CM5分别属于根瘤菌属(Bradyrhizobium)、链霉菌属(Streptomyces)、不动杆菌属(Acinetobacter)。CM5、CM6两株菌对红花生长有明显的促进作用。
关键词:红花;溶磷细菌;筛选和鉴定;促生
中图分类号: S154.3文献标志码: A文章编号:1002-1302(2014)09-0318-05
通信作者:张霞,教授,硕士生导师,从事植物遗传研究。E-mail:xiazh@shzu.edu.cn。磷是植物生长发育所必需的营养元素[1],缺磷可导致农作物产量明显降低。土壤全磷含量虽然较高,但易与土壤中的金属离子相结合形成难溶的磷化物,只有少量磷肥可以被植物吸收利用。当季的作物对施入磷肥的利用率仅为25%,因此,磷被认为是限制性营养元素[2]。红花生长发育受化学肥料尤其是磷酸盐肥料影响较大,但使用这些化学肥料会增加土壤及水污染,过量使用磷肥会造成水体富营养化[3],同时会积累一些重金属,威胁人类的健康。另一方面,长期使用化学肥料会导致土壤结构退化[4]。如今,基于化学肥料价格及对农业系统可持续发展的考虑,人们对生物肥料的关注越来越高。
一些细菌可以提供植物生长所需的磷,同时扮演了溶磷微生物的角色。土壤中存在大量有溶磷能力的微生物,称为溶磷微生物[5]。溶磷微生物能将难以被植物吸收的磷元素转化为易于吸收利用的状态,提高磷元素的利用率,从而提高作物产量,也减少了磷肥的过度使用。利用溶磷微生物将难溶性磷酸盐转变为可溶性磷是非常有必要的。溶磷微生物提高有效磷含量的同时,还可改善施用化学磷肥所带来的环境污染。因此研究根际磷细菌,对发展溶磷微生物肥料具有重要的现实意义。目前已有的溶磷微生物种类很多,有细菌、真菌、放线菌等,溶磷能力差异较大[6]。所以,从根际土中筛选出溶磷能力好的溶磷微生物,制成生物肥料来提高磷素利用率成为研究热点。
本研究从红花根际土中筛选出8株溶磷细菌,并对8株溶磷细菌进行了鉴定,同时在温室条件下,选取3株溶磷效果较好并且具有良好溶磷稳定性的解磷菌接种红花,研究了3株解磷菌对红花盛花期生长的影响。该研究以期为红花生物肥料菌种资源与应用提供一定的理论依据。
1材料与方法
1.1材料
供试植物:红花(Carthamus tinctorius L.)种子,品种“新红4号”,产地新疆石河子。
供试培养基:蒙金娜无机培养基:葡萄糖 10 g,琼脂20 g,(NH4)2SO4 0.5 g,NaCl 0.3 g,KCl 0.3 g,FeSO4·7H2O 0.03 g,MgSO4·4H2O 0.03 g,MgSO4·7H2O 0.3 g,磷矿粉 10 g,酵母膏0.4 g,蒸馏水1 000 mL,pH值7.0~7.5;蒙金娜无机液体培养基:配方同蒙金娜无机培养基,不加琼脂。
蒙金娜有机培养基:葡萄糖 10g,琼脂20g,(NH4)2SO4 0.5 g,NaCl 0.3 g,KCl 0.3 g,FeSO4·7H2O 0.03g,MgSO4·4H2O 0.03 g,MgSO4·7H2O 0.3 g,卵磷脂0.2 g,碳酸钙 5 g,酵母膏0.4 g,蒸馏水1 000 mL,pH值7.0~7.5;蒙金娜有机液体培养基:配方同蒙金娜有机培养基,不加琼脂。
溶磷细菌纯培养保藏培养基(NA):牛肉膏5.0 g,蛋白胨10.0 g,NaCl 5.0 g,琼脂20 g,水1 000 mL,pH值7.0~7.2;溶磷细菌培养培养基(NB):配方同NA,不添加琼脂。
1.2方法
1.2.1红花室内培育选取粒大、饱满、色白的红花种子,在40 ℃温水中浸泡10 min,转入冷水中冷却,取出晾干后播种。每盆播20粒红花种子,室温15 ~20 ℃下培养至发芽。
1.2.2红花大田定植移栽红花幼苗之前,对移栽地进行精耕细耙,以减少样地空间异质性。待红花幼苗生长30 d后,选择生长状况相对一致的幼苗移栽至试验大田中。大田设在石河子大学节水灌溉试验站(兵团灌溉试验站石河子大学分站)(北纬40°16′58.4″~46°43′31.8″,东经82°30′32″~89°01′02″)。此区域属典型大陆性干旱半干旱气候,样地具体概况见表1。
1.2.3土壤样品的采集红花伸长期从样地里挖出整株红花,抖掉根周围松散的土壤,刷下附着在红花根上的土壤,装入封口袋密封后带回实验室,过1 mm筛后,放入4 ℃冰箱保存备用。
1.2.4红花根际溶磷细菌分离纯化及筛选称取5 g保存的土壤样品,加入45 mL无菌水与10粒灭菌玻璃珠,常温200 r/min振荡25 min,按10倍稀释法稀释样品。采用10-4、10-5、10-6稀释浓度,使用蒙金娜固体培养基培养。30 ℃恒温培养5 d。测量解磷圈直径(D)、菌落直径(d),根据D/d大小来初步确定菌株的解磷能力。挑取单菌落至NA培养基培养2~3 d,置于4 ℃冰箱保存。解磷细菌的复筛采用钼锑抗比色法[7]。通过初筛,选择8株溶磷圈较大的菌株,分别接种于30 mL NB培养基中,120 r/min、28 ℃培养36 h,并用无菌水制成108 CFU/mL悬浮菌液。每瓶接种1 mL细菌菌液于灭菌的蒙金娜液体摇瓶培养基中,重复3次。以接种等量灭活细菌液作对照,摇床培养(28 ℃,160 r/min)5 d。钼锑抗比色法测定上清液有效磷含量及测定上清液pH值。endprint
1.2.5溶磷细菌的鉴定
1.2.5.1理化性质及形态学分类按照文献[8]作形态与生理生化分析。
1.2.5.216S rDNA鉴定使用细菌16S rDNA的通用引物8F(5′-AGAGTTTGATCCTGGCTCAG-3′)和1492R(5′-CGGTTACCTTGTTACGACTT-3′)进行扩增。PCR扩增经琼脂糖凝胶电泳检测产物后,送至北京三博远志测序部测序。将得到的序列提交到GenBank数据库,利用BLAST与GenBank数据库中的序列进行比对,用ClustalX1.81软件将相近序列进行多重序列分析,利用MEGA V.4.0软件构建系统发育树(Bootstrap=1 000)。
1.2.6溶磷细菌的温室试验将3株溶磷效果好的溶磷菌活化,接种于液体培养基中,28 ℃、200 r/min振荡培养2 d后,发酵液离心(4 ℃,4 000 r) 5 min,无菌生理盐水洗菌体3次,用无菌生理盐水制成108 CFU/mL悬浮菌液,接种红花幼苗(苗龄20 d),每株接种量8 mL,以接种生理盐水作对照,每个处理3个重复,温室培养,培养基质为土壤 ∶蛭石 ∶沙子=3 ∶1 ∶1的混合基质,每盆4 kg,土壤有机质为9.8 g/kg,速效磷为6.5 mg/kg,速效钾为155 mg/kg,碱解氮为35.9 mg/kg。红花接种90 d后测株高、茎粗、叶片数、根长、茎干质量。
2结果与分析
2.1红花根际磷细菌的分离与筛选
用选择培养基平板从红花根际土中分离出10株能产生溶磷圈的细菌。利用解磷圈直径(D)、菌落生长直径(d)的比值作为解磷菌相对解磷能力的指标,10个菌株D/d值在1.87~4.03,D/d>4的有1株,2 2.2溶磷细菌溶磷能力测定 测定结果见表3。不同菌株的溶磷量在181.34~283.14 mg/L之间,显著高于对照(P<0.05),说明8株菌株都有较强的溶磷能力。其中CM6的总解磷量为283.14 mg/L,显著高于其他菌株,解磷效果最强。CM4的总解磷量最低,为181.34 mg/L。 2.3溶磷细菌的鉴定 2.3.1溶磷细菌的形态学特征对8株溶磷细菌的形态及菌落特征观察,可以得到,菌株CM4、CM7、CM8为芽孢革兰形,表面光滑,湿润,边缘整齐,除CM5无鞭毛外,CM1、CM2、CM6均有极生鞭毛;CM3为革兰氏阳性菌,菌落灰白色,不规则形,干燥,不透明,不易挑取,结果见表4。 2.3.2溶磷细菌的生理生化特性对8株溶磷细菌的生理生化鉴定有氧化酶、接触酶、淀粉水解、吲哚试验、甲基红测试等,结果见表5。8株菌在接触媒试验中均表现为阳性,而在氧化酶反应、淀粉酶试验及吲哚试验中,阴性与阳性各占50%,甲基红试验中,阳性为12.5%。其中,CM1、CM6淀粉水解及甲基红反应为阴性,其余均为阳性;CM4、CM7、CM8甲基红反应、氧化酶反应为阴性,其余均为阳性;CM2淀粉水解、甲基红反应及吲哚反应为阴性,其余为阳性;CM3全为阳性、CM5接触酶反应及需氧反应为阳性,其余均为阴性。 2.3.316SrDNA 鉴定分别以8个菌株DNA为模板,采用表58株溶磷细菌生理生化特性 试验名称CM1CM2CM3CM4CM5CM6CM7CM8需氧反应++++++++氧化酶试验+++--+--过氧化氢酶试验++++++++淀粉酶试验--++--++甲基红试验--+-----吲哚试验+-++-+--注:“-”为阴性反应;“+”为阳性反应。 通用引物扩增出长约1 500 bp的片段,琼脂糖凝胶电泳检测后进行测序。将8株菌16S rDNA基因序列提交到GenBank数据库,其登录号分别为KC844218、KC844219、KC844220、KC844221、KC844222、KC844223、KC844224、KC844225,通过Blast工具在GenBank数据库中与已发表的16S rDNA基因序列进行同源性比对,与相近序列联配比较构建系统发育树。由系统发育树(图1)可知,8株菌隶属于假单胞菌属(Pseudomonas)、根瘤菌属(Bradyrhizobium)、链霉菌属(Streptomyces)、芽孢杆菌属(Bacillus)、不动杆菌属(Acinetobacter),分别与已知种荧光假单胞菌(Pseudomonas fluorescens)、解淀粉芽孢杆菌(Bacillus amyloliquefaciens)、地衣芽孢杆菌(Bacillus licheniformis)、链霉菌属(Streptomyces)、苜蓿中华根瘤菌(Sinorhizobium meliloti)、乙酸钙不动杆菌(Acinetobacter calcoaceticus)、铜绿色假单胞菌(Pseudomonas)、芽孢杆菌(Bacillus sp.)系统发育关系接近,序列同源性分别达到99%。再结合细菌的培养特征、生理生化测定结果和系统发育分析结果,初步确定8株菌中:CM1 和 CM6属于假单胞菌属(Pseudomonas),CM4、CM7、CM8属于芽孢杆菌属(Bacillus),CM2、CM3、CM5分别属于根瘤菌属(Bradyrhizobium)、链霉菌属(Streptomyces)、不动杆菌属(Acinetobacter)。菌株CM1、CM2、CM3、CM4、CM5、CM6、CM7、CM8分别鉴定为Pseudomonas sp.、Sinorhizobium meliloti、Streptomyces、Bacillus licheniformis、Acinetobacter calcoaceticus、Pseudomonas fluorescens、Bacillus amyloliquefaciens、Bacillus mojavensis。
2.4解磷菌菌株对红花的促生长作用
在温室条件下,将红花分别接种CM1、CM5、CM6,90 d后测株高、茎粗、叶片数、根长、茎干质量。结果如表6所示,接种3株溶磷菌后,红花的株高、茎粗、叶片数、根长、茎干质量,菌处理的各项指标均超过未处理的对照,除CM1外,接种CM5、CM6各项指标显著提高(P<0.05),说明除CM1外,其余两株溶磷细菌对红花生长具有促进作用。
3讨论
从红花根际土壤中分离出8株具有较好解磷效果的溶磷细菌,分别为CM1、CM2、CM3、CM4、CM5、CM6、CM7、CM8。经生理生化及16S rDNA 鉴定后,分为以下几个属:假单胞菌属(Pseudomonas)、根瘤菌属(Bradyrhizobium)、链霉菌属(Streptomyces)、芽孢杆菌属(Bacillus)、不动杆菌属(Acinetobacter),菌株CM1、CM2、CM3、CM4、CM5、CM6、CM7、CM8分别鉴定为Pseudomonas sp.、Sinorhizobium meliloti、Streptomyces、Bacillus licheniformis、Acinetobacter calcoaceticus、Pseudomonas fluorescens、Bacillus amyloliquefaciens、Bacillus mojavensis。
接种3株具有稳定遗传能力的溶磷细菌CM1、CM5、CM6后,CM5、CM6菌株显著增加了红花植株株高、茎粗、叶片数、根长、茎干重,说明这2株溶磷细菌能够促进红花对营养物质的吸收。这3株菌被定义为促进植物生长的根际细菌[10],能够促进植物生长,有效阻止病原菌侵染植物。有研究结果表明,接种溶磷微生物后,成功地减少了植物染病的概率[11-12]。
多数研究者认为,微生物的解磷作用,主要取决于其分泌有机酸的能力以及它们的螯合能力[13]。Fankem等发现解磷微生物解磷能力随着土壤pH值降低而升高,与分泌的有机酸产物相关[14]。Hinsinger发现根部释放的有机配体也能够改变土壤中有效磷的浓度[15]。相关研究发现荧光假单胞菌分泌葡萄糖酸和草酸;芽孢杆菌属分泌柠檬酸和葡萄糖酸,解淀粉芽孢杆菌及地衣芽孢杆菌分别分泌乳酸和异戊酸[16]。本试验中,pH值与对照相比较有所降低,说明8株菌产生相应的酸,但解磷能力与分泌有机酸这两者之间是否有必然的联系,需要进一步研究。
解磷微生物优势之一是其繁殖速率,能够满足植物根际对磷的需求。印度农业研究所研究溶磷菌对小麦和水稻产量及磷吸收影响的研究结果表明:接种溶磷菌使其产量及对磷的吸收均有所增加[17]。Ratti等研究表明,柠檬草接种溶磷微生物后,与对照相比,其高度及生物量都显著升高[18]。Hazarika等指出,使用溶磷微生物肥料显著增加了茶树植株高度[19]。Mustafa等研究发现,接种磷细菌对其他植物也存在促进效果[20]。Belimov等的研究结果表明,土壤接种混合微生物后,植物根部对磷素及氮素的吸收明显升高[21]。生物肥料的施用对农业生产及保护环境具有重大意义。本试验以红花根际土为研究对象,从红花根际土中分离、筛选及鉴定出8株溶磷能力好的解磷细菌。选取3株溶磷效果较好并且具有稳定遗传能力的溶磷细菌接种红花,其中两株菌能够促进红花生长。本研究为红花生物肥料菌种资源提供一定的理论基础,对红花微生物肥料研究具有一定意义。后期将会重点研究红花菌根真菌接种后对红花根际磷细菌的影响,以期了解菌根真菌、解磷细菌及植物营养三者之间的关系,为微生物肥料的研究提供理论依据。
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[11]Zayed G,Abdel-Motaal H. Bio-active composts from rice straw enriched with rock phosphate and their effect on the phosphorous nutrition and microbial community in rhizosphere of cowpea[J]. Biores Technol,2005,96:929-935.
[12]Peix A,Rivas-Boyero A A,Mateos P F,et al. Growth promotion of chickpea and barley by a phosphate solubilizing strain of Mesorhizobium mediterraneum under growth chamber conditions[J]. Soil Biology & Biochemistry,2001,33:103-110.
[13]Delvasto P,Valverde A,Ballester A,et al. Characterization of brushite as a re-crystallization product formed during bacterial solubilization of hydroxyapatite in batch cultures[J]. Soil Biology & Biochemistry,2006,38(9):2645-2654.
[14]Fankem H,Nwaga D,Deubel A,et al. Occurrence and functioning of phosphate solubilizing microorganisms from oil palm tree(Elaeis guineensis) rhizosphere in Cameroon[J]. African J Biotech,2006,5:2450-2460.
[15]Hinsinger P. Bioavailability of soil inorganic P in the rhizosphere as affected by root-induced chemical changes:a review[J]. Plant and Soil,2001,237:173-195.
[16]Sharma A K. Bio-fertilizers for sustainable agriculture[J]. Agrobios Indian Pub,2002:407.
[17]Sharma S N,Prasad R. Yield and P uptake by rice and wheat grown in a sequence as influenced by phosphate fertilization with diammonium phosphate and Mussoorie rock phosphate with or without crop residues and phosphate solubilizing bacteria[J]. Journal of Agricultural Science,2003,141(3/4):359-369.
[18]Ratti N,Kumar S,Verma H N,et al. Improvement in bioavailability of tricalcium phosphate to Cymbopogon martinii var. motia by rhizobacteria,AMF and Azospirillum inoculation[J]. Microbiol Res,2001,156:145-149.
[19]Hazarika D K,Taluk D N,Phookan A K,et al. Influence of vesicular arbascular mycorrhizal fungi and phosphate solubilizng bacteria on nursery establishment and growth of tea seedlings in Assam[R]. Jorhat-Assam,India:Assam Agricultural University,2000.
[20]Mustafa Y,Bilenc S,CakmakaiR,et al. Effect of plant growth-promoting bacteria and soil compaction on barley seeding growth,nutrient uptake,soil properties and rhizosphere microflora[J]. Biol Fertile Soil,2006,42(4):350-357.
[21]Belimov A A,Kojemiakov A P. Chuvarliyeva CV interaction between barley and mixed cultures of nitrogen fixing and phosphate-solubilizing bacteria[J]. Plant and Soil,1995,173:29-37.李范,李娜,陈建中,等. 基于磷脂脂肪酸提取方法的微生物群落结构研究[J]. 江苏农业科学,2014,42(9):323-325.endprint
[7]鲍士旦. 土壤农化分析[M]. 3版.北京:中国农业出版社,2000:74-76.
[8]东秀珠,蔡妙英. 常见细菌系统鉴定手册[M]. 北京:科学出版社,2001.
[9]叶劲松,吴克,俞志敏. 1株无机磷细菌筛选及溶磷能力的测定[J]. 江苏农业科学,2013,41(6):333-335.
[10]Kloepper J W,Schroth M N. Plant growth-promoting rhizobacteria on radishes[C]//Proceedings of the 4th International Conference on Plant Pathogenic Bacteria Vol Ⅱ. Tours:Gilbert-Clary,1978:879-882.
[11]Zayed G,Abdel-Motaal H. Bio-active composts from rice straw enriched with rock phosphate and their effect on the phosphorous nutrition and microbial community in rhizosphere of cowpea[J]. Biores Technol,2005,96:929-935.
[12]Peix A,Rivas-Boyero A A,Mateos P F,et al. Growth promotion of chickpea and barley by a phosphate solubilizing strain of Mesorhizobium mediterraneum under growth chamber conditions[J]. Soil Biology & Biochemistry,2001,33:103-110.
[13]Delvasto P,Valverde A,Ballester A,et al. Characterization of brushite as a re-crystallization product formed during bacterial solubilization of hydroxyapatite in batch cultures[J]. Soil Biology & Biochemistry,2006,38(9):2645-2654.
[14]Fankem H,Nwaga D,Deubel A,et al. Occurrence and functioning of phosphate solubilizing microorganisms from oil palm tree(Elaeis guineensis) rhizosphere in Cameroon[J]. African J Biotech,2006,5:2450-2460.
[15]Hinsinger P. Bioavailability of soil inorganic P in the rhizosphere as affected by root-induced chemical changes:a review[J]. Plant and Soil,2001,237:173-195.
[16]Sharma A K. Bio-fertilizers for sustainable agriculture[J]. Agrobios Indian Pub,2002:407.
[17]Sharma S N,Prasad R. Yield and P uptake by rice and wheat grown in a sequence as influenced by phosphate fertilization with diammonium phosphate and Mussoorie rock phosphate with or without crop residues and phosphate solubilizing bacteria[J]. Journal of Agricultural Science,2003,141(3/4):359-369.
[18]Ratti N,Kumar S,Verma H N,et al. Improvement in bioavailability of tricalcium phosphate to Cymbopogon martinii var. motia by rhizobacteria,AMF and Azospirillum inoculation[J]. Microbiol Res,2001,156:145-149.
[19]Hazarika D K,Taluk D N,Phookan A K,et al. Influence of vesicular arbascular mycorrhizal fungi and phosphate solubilizng bacteria on nursery establishment and growth of tea seedlings in Assam[R]. Jorhat-Assam,India:Assam Agricultural University,2000.
[20]Mustafa Y,Bilenc S,CakmakaiR,et al. Effect of plant growth-promoting bacteria and soil compaction on barley seeding growth,nutrient uptake,soil properties and rhizosphere microflora[J]. Biol Fertile Soil,2006,42(4):350-357.
[21]Belimov A A,Kojemiakov A P. Chuvarliyeva CV interaction between barley and mixed cultures of nitrogen fixing and phosphate-solubilizing bacteria[J]. Plant and Soil,1995,173:29-37.李范,李娜,陈建中,等. 基于磷脂脂肪酸提取方法的微生物群落结构研究[J]. 江苏农业科学,2014,42(9):323-325.endprint
[7]鲍士旦. 土壤农化分析[M]. 3版.北京:中国农业出版社,2000:74-76.
[8]东秀珠,蔡妙英. 常见细菌系统鉴定手册[M]. 北京:科学出版社,2001.
[9]叶劲松,吴克,俞志敏. 1株无机磷细菌筛选及溶磷能力的测定[J]. 江苏农业科学,2013,41(6):333-335.
[10]Kloepper J W,Schroth M N. Plant growth-promoting rhizobacteria on radishes[C]//Proceedings of the 4th International Conference on Plant Pathogenic Bacteria Vol Ⅱ. Tours:Gilbert-Clary,1978:879-882.
[11]Zayed G,Abdel-Motaal H. Bio-active composts from rice straw enriched with rock phosphate and their effect on the phosphorous nutrition and microbial community in rhizosphere of cowpea[J]. Biores Technol,2005,96:929-935.
[12]Peix A,Rivas-Boyero A A,Mateos P F,et al. Growth promotion of chickpea and barley by a phosphate solubilizing strain of Mesorhizobium mediterraneum under growth chamber conditions[J]. Soil Biology & Biochemistry,2001,33:103-110.
[13]Delvasto P,Valverde A,Ballester A,et al. Characterization of brushite as a re-crystallization product formed during bacterial solubilization of hydroxyapatite in batch cultures[J]. Soil Biology & Biochemistry,2006,38(9):2645-2654.
[14]Fankem H,Nwaga D,Deubel A,et al. Occurrence and functioning of phosphate solubilizing microorganisms from oil palm tree(Elaeis guineensis) rhizosphere in Cameroon[J]. African J Biotech,2006,5:2450-2460.
[15]Hinsinger P. Bioavailability of soil inorganic P in the rhizosphere as affected by root-induced chemical changes:a review[J]. Plant and Soil,2001,237:173-195.
[16]Sharma A K. Bio-fertilizers for sustainable agriculture[J]. Agrobios Indian Pub,2002:407.
[17]Sharma S N,Prasad R. Yield and P uptake by rice and wheat grown in a sequence as influenced by phosphate fertilization with diammonium phosphate and Mussoorie rock phosphate with or without crop residues and phosphate solubilizing bacteria[J]. Journal of Agricultural Science,2003,141(3/4):359-369.
[18]Ratti N,Kumar S,Verma H N,et al. Improvement in bioavailability of tricalcium phosphate to Cymbopogon martinii var. motia by rhizobacteria,AMF and Azospirillum inoculation[J]. Microbiol Res,2001,156:145-149.
[19]Hazarika D K,Taluk D N,Phookan A K,et al. Influence of vesicular arbascular mycorrhizal fungi and phosphate solubilizng bacteria on nursery establishment and growth of tea seedlings in Assam[R]. Jorhat-Assam,India:Assam Agricultural University,2000.
[20]Mustafa Y,Bilenc S,CakmakaiR,et al. Effect of plant growth-promoting bacteria and soil compaction on barley seeding growth,nutrient uptake,soil properties and rhizosphere microflora[J]. Biol Fertile Soil,2006,42(4):350-357.
[21]Belimov A A,Kojemiakov A P. Chuvarliyeva CV interaction between barley and mixed cultures of nitrogen fixing and phosphate-solubilizing bacteria[J]. Plant and Soil,1995,173:29-37.李范,李娜,陈建中,等. 基于磷脂脂肪酸提取方法的微生物群落结构研究[J]. 江苏农业科学,2014,42(9):323-325.endprint