Phytoremediation, assisted by endophytes, showed great promise for the efficient remediation of chromium (Cr)-contaminated soil. Three endophytic bacterial strains (SE16, SE19, and SE47) were isolated from various tissues of Sorghum sudanense. The pot experiment was designed to evaluate the potential of these endophytes, applied individually or in combination, to enhance the phytoremediation efficiency of S. sudanense in Cr-contaminated soil. The results demonstrated that inoculation with endophytes increased plant height and root length by 26.4-49.2% and by 63.5-122.8%, respectively. With the exception of the SE47 treatment, the fresh weights of the shoot increased significantly, reaching 2.01-3.08 times that of the non-inoculated control. Endophyte inoculation also led to a marked reduction in the Cr content in the shoots and roots of S. sudanense. The chlorophyll content increased, while the malonaldehyde (MDA) content decreased significantly after inoculation, indicating the alleviation of the cytotoxicity of Cr. The peroxidase (POD) activity in both the shoots and roots of S. sudanense decreased after inoculation. In shoots, catalase (CAT) activity was significantly lower in the combined inoculation treatments than in the non-inoculated control. In contrast, single inoculation treatments significantly increased CAT activity in roots compared to the control. Furthermore, endophyte inoculation increased soil organic matter (OM) and alkaline phosphatase activity. At the genus level, endophyte inoculation increased the relative abundance of Delftia and Saccharimonadales, which may contribute to reducing the toxic effects of heavy metals to plants. Our findings indicated that the endophytic bacteria are promising candidates for promoting plant growth and facilitating microbe-assisted phytoremediation in heavy metal-contaminated soil.

Nitrogen (N) removal from saline wastewater has emerged as a key concern to safeguard environment. High salinity can impede the growth of bacteria responsible for nitrogen removal. The identification of salt-tolerant bacteria capable of nitrogen removal is thus important for wastewater treatment. In this study, a novel strain, Alcaligenes aquatilis DN-1, capable of aerobic-heterotrophic nitrogen removal (AHNR) was isolated from wastewater. The strain DN-1 showed 100 %, 99.97 %, and 85.24 % efficiencies for removing ammonium, nitrite, and nitrate, respectively. Particularly, strain DN-1 exhibited excellent ammonium removal efficiency under 0-6 % salinity. A maximum nitrogen removal rate of 98.92 % was achieved at NaCl concentration of 6 %. Results of transcriptomic analysis indicated that up-regulation of gdhA, gltB and gltD genes was observed, which were involved in the assimilation pathway of ammonium removal. Ammonium removal pathway from hypersaline wastewater by strain DN-1 was accomplished mainly through assimilation. Genes involved in synthesis of ectoine and 5-hydroxyectoine, i.e., ectA, ectB, ectC and ectD, showed significantly high levels of transcriptional expressions, indicating that strain DN-1 balanced osmotic pressure by accumulating ectoine and 5-hydroxyectoine to withstand salinity-induced osmoadaptation. Meanwhile, genes associated with oxidative stress (trxB, trxC, dsbA, dsbB, dsbC and dsbD) were also upregulated to some extent. Genes involved in osmoadaptation and oxidative stress cooperated with ammonium metabolism pathways to counteract salt stress. The study indicated that the isolatedstrain for was highly efficient in eliminating ammonium from wastewater. The findings further offered valuable insights into the adaptation mechanisms of Alcaligenes aquatilis DN-1 in salt wastewater.

Two Gram-staining-positive, non-motile and non-spore-forming bacterial strains, designated as 9H2 T and YDN13, were isolated from a phosphate mine in Yunnan Province, China. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strains 9H2 T and YDN13 belong to the genus Microbacterium . Results show that strains 9H2 T and YDN13 occupied a distinct position within the genus Microbacterium and showed the highest 16S rRNA gene sequence similarity of 97.6% with the type strains of Microbacterium thalassium CCTCC AB 2020140 T , followed by 97.5% with Microbacterium hydrocarboxydans DSM 16089 T and 97.3% with Microbacterium stercoris CCTCC AA 2018028 T . In the phylogenetic trees based on 16S rRNA gene sequences, strains 9H2 T and YDN13 were closely related to M. stercoris CCTCC AA 2018028 T and Microbacterium sediminicola YM 10-847 T . Strains 9H2 T and YDN13 showed the highest values of an orthologous average nucleotide identity (84%) and a digital DNA–DNA hybridization (49%) with M. stercoris CCTCC AA 2018028 T , followed by an orthologous average nucleotide identity of 76.0% and a digital DNA–DNA hybridization value of 17.9% with M. thalassium CCTCC AB 2020140 T . The respiratory menaquinones were MK-11, MK-12, MK-10 and MK-13. The major fatty acid profile contained anteiso-C 15 : 0 , iso-C 16 : 0 and anteiso-C 17 : 0 . The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, three unidentified phospholipids and one unidentified glycolipid. The whole-cell sugars included galactose and glucose. The peptidoglycan hydrolysate contained glutamate, glycine, ornithine and alanine. The DNA G+C contents were 71.1 mol%. Phenotypic, phylogenetic, chemotaxonomic and genomic analyses revealed that strains 9H2 T and YDN13 represent a novel species of Microbacterium , for which the name Microbacterium phosphatis sp. nov. was proposed. The type strain is 9H2 T (MCCC 1K08680 T =KCTC 59053 T =CGMCC 1.60061 T ).

In order to reduce the cost of solid-state fermentation of Paeciloids lilacinus, using Scutellaria baicalensis residue as the substrate, the medium composition and fermentation conditions were optimized, and the effects of different chitin content on chitinase-producing activity were investigated.The results showed that the optimal medium composition for solid-state fermentation of P. lilacinus was as follows: S. baicalensis residue 20 g, corn flour 0.8 g, urea 0.02 g, and water content 80%. The optimum culture conditions of solid-state fermentation were as follows: culture temperature 28 ℃,inoculum 10%, and time 7 d. Under the optimal condition, the conidia number could reach 8.98 ×109CFU/g. The chitinase-producing activity of the strain was significantly increased when the chitin addition was 0.9%（P＜0.05）.

In order to improve the digestibility of animal coarse feed, the fermentation conditions of lignin degrading enzyme production by Trametes hirsuta XYG422 were optimized by user of single factor and orthogonal experiments. Scutellaria residue was used as the substrate. The results showed that the optimized medium composition for solid fermentation of Trametes hirsuta XYG422 was as followed: Soluble starch ∶ ammonium sulfate 3∶1, 3 mmol/L Cu2+ and 1.8 mmol/L Mn2+. Under the conditions, manganese peroxidase activity reached 179.37 nmol/(min·g), laccase activity reached 41.68 U/g. The research has certain guiding significance for the production and application of Trametes hirsuta , and also provides novel opportunities to develop livestock feeds with improved fiber digestibility.

In this work, the Pb adsorption and removal ability of biochar from simulated Pb(II)-contaminated wastewater, adsorption isotherms, kinetics, and thermodynamics were studied. Adsorption characteristics of biochar on Pb(II) were analyzed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscope with energy dispersive spectrometer (SEM-EDS). The influence of the pH of the solution, the contact time, and the biochar dose on the removal of Pb(II) were investigated by single-factor design and response surface analysis. With the increase in biochar dose from 2 g/L to 4 g/L in wastewater, the Pb(II) amount adsorbed on biochar reduced from 21.3 mg/g to 17.5 mg/g. A weakly acidic environment was more conducive to the ligand exchange between Pb(II) ions and biochar. Pb(II) adsorption kinetics of biochar showed that the Pseudo-first-order model was more suitable than other employed models to describe the adsorption process. During the isothermal adsorption process, Langmuir and Freundlich’s isotherms fitted the adsorption data very well (R2 > 96%). The Pb (II) adsorption onto biochar was spontaneous in the specified temperature range (298–318 K) and the process was exothermic. Simultaneously, the optimal conditions were a pH of 5, a contact time of 255 min, and a biochar dose of 3 g/L, under which the maximum predicted Pb(II) removal efficiency was 91.52%.

Peanut stem rot caused by Sclerotium rolfsii Sacc. is the most common disease of peanut worldwide and has become increasingly serious in recent years. This study is aimed at obtaining peanut endophytic bacteria with high antagonistic/protective effects against peanut stem rot. In total, 45 bacterial strains were isolated from healthy peanut plants from a severely impacted area. Of these, 6 exhibited antagonistic activity against S. rolfsii , including F-1 and R-11 with the most robust activity with an inhibition zone width of 20.25 and 15.49 mm, respectively. These two were identified as Bacillus sp. and Burkholderia sp., respectively, based on morphological, physiological, and biochemical characteristics and 16S rDNA sequencing. To the best of our knowledge, this is the first study to report the Burkholderia sp. antagonistic effect on S. rolfsii as a biological control agent for peanut stem rot. Their culture filtrates potently inhibited the hyphal growth, sclerotial formation, and germination of S. rolfsii . Also, the strain-produced volatile compounds inhibited the fungal growth. Pot experiments showed that F-1 and R-11 significantly reduced the peanut stem rot disease with the efficacy of 77.13 and 64.78%, respectively, which was significantly higher compared with carbendazim medicament (35.22%; P < 0.05). Meanwhile, F-1 and R-11 improved the activity of plant defense enzymes such as phenylalaninase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) enhancing the systemic resistance of the peanut plants. This study demonstrated that Bacillus sp. F-1 and Burkholderia sp. R-11, with a strong antagonistic effect on S. rolfsii , can be potential biocontrol agents for peanut stem rot.

为了获得耐受各种不良环境的多环芳烃(PAHs)降解菌,利用多环芳烃(菲和芘)、重金属(Cu2+、Cr6+)以及氮源缺乏培养基从南阳石油污染土壤中分离筛选一株耐受不良环境的菲芘降解菌,通过形态学特征和分子生物学方法鉴定菌株,并研究菌株对重金属Cr6+和Cu2+、氮源缺乏及酸碱的耐受程度,进一步探究在这些不良环境下菌株对多环芳烃菲和芘的降解效果.结果表明,菌株属于根瘤菌属,命名为F3-1.在液体培养基中,菌株F3-1对重金属Cr6+和Cu2+的耐受质量浓度均为20 mg/L;在氮源缺乏的情况下,菌株能够正常生长;菌株F3-1在pH 5.0和pH 7.4环境下均可以正常生长;菌株F3-1在不良环境下对多环芳烃菲和芘均有很好的降解效果,5 d后在pH 7.4条件下对菲(50 mg/L)的降解率为35.54％,在pH 5.0条件下对芘(50 mg/L)的降解率为53.43％.

本试验通过高通量测序技术研究花生不同组织内生真菌群落多样性,一共获得763200条有效序列,聚类后得到308个OTU,隶属于9个门,25个纲,51个目,107个科,155个属.根部内生真菌优势属为镰刀菌属(Fusarium)、曲霉属(Aspergillus)、丝孢酵母属(Trichosporon)、Apiotrichum和篮状菌属(Talaromyces),相对丰度分别为13.35％、10.74％、8.32％、6.29％和5.09％;茎部内生真菌优势属为Apiotrichum、丝孢酵母属(Tri-chosporon)、皮状丝孢酵母属(Cutaneotrichosporon)和曲霉属(Aspergillus),相对丰度分别为17.99％、13.81％、7.60％和5.92％;叶部内生真菌优势属为小光壳属(Leptosphaerulina)和暗球腔菌属(Phaeosphaeria),相对丰度分别为65.64％和27.18％;花部内生真菌优势属为小光壳属(Leptosphaerulina),相对丰度达到95.45％.经FUNGuild软件分析,花生内生真菌共包含地衣共生真菌、未定义腐生菌、动物病原菌、内生菌、木腐菌、植物病原菌、粪生菌、丛枝菌根真菌等17种生态功能群.

This study aimed to investigate the biodegradation of three distinct PAHs: Phenanthrene (Phe), Pyrene (Pyr), and Benzo[a]pyrene (BaP) by using fermentation broth from T. hirsuta culture medium. The results revealed that 2,5-xylidine ameliorates laccase production in T. hirsuta fermentation medium. After 6 days of incubation, T. hirsuta zlh237 fermentation broth (6-day-FFB) showed a higher degradation rate for three PAHs than 11-day fermentation broth (11-day-FFB). Final Phe, Pyr, and BaP degradation rates of 6-day-FFB were 89.35%, 85.92%, and 89.45%, respectively, on the 5th day of incubation. The PAHs biodegradation rate of 6-day-FFB in natural soil samples were lower than in sterilized soil. The Phe, Pyr, and BaP degradation rates of 6-day-FFB were 54.49%, 46.76%, and 51.93% in sterilized soil samples, and 39.37%, 34.00%, 33.99% in natural soil samples, after 15 days incubation, respectively. The high-throughput sequencing analysis revealed that the 6-dayFFB altered the bacterial community structure and enhanced microbial biodiversity of contaminated soil. The PAHs-contaminated soils incubated with 6-day-FFB showed significant increase in well color development than the controls. Principal Component Analysis of Biolog data differentiated the effect of 6-day-FFB and sterilized 6-day-FFB on contaminated soils. It implied that T. hirsuta zlh237 restored the microbiological functioning of the PAHs contaminated soils.

采用盆栽试验探讨了不同剂量棘孢木霉SFC-3菌剂对小麦生理生化指标及生防效果的影响.结果 表明:施用SFC-3菌剂对小麦的株高和主根长度没有明显影响(P＞0.05),但可提高小麦的出芽率,当施菌剂量为1.0～2.0 g/kg时小麦的出芽率显著高于对照(P＜0.05);施用SFC-3菌剂小麦叶片中叶绿素含量和可溶性蛋白含量与对照相比均显著增加(P＜0.05),其中施菌剂量为1.0 g/kg时最高.而小麦叶片中的MDA含量在施菌剂量为1.0 g/kg时显著低于对照和其他施菌处理(P＜0.05);当施菌剂量为0.5～1.0 g/kg时,小麦叶片中SOD和POD活性显著高于对照,进一步增加施菌剂量,小麦叶片中SOD和POD活性均随之显著降低(P＜0.05).当施菌剂量为1.5 g/kg和2.0 g/kg时每克根中小麦孢囊线虫2龄幼虫数量最少,发病级别最低,其相对防效分别为88.68％和87.04％,其次为施菌剂量1.0 g/kg的处理,其相对防效为80.50％.施用不同剂量的棘孢木霉SFC-3菌剂对小麦生理生化指标均有不同程度的影响,并且当施菌剂量为1.0 g/kg时对小麦生长和孢囊线虫的防治效果最好.

为筛选对花生白绢病菌(Sclerotium rolfsii Sacc.)具有高效拮抗活性的细菌菌株,采用平板对峙法和菌丝生长速率法对4株细菌进行抑菌活性的测定,并对筛选的高效拮抗菌株进行鉴定和活性物质稳定性研究.结果表明,菌株WS3-1对花生白绢病菌的抑制作用最强,其发酵滤液对病菌的抑菌率达95.04％.通过细菌形态特征、生理生化特征及16S rDNA和gyrB序列分析,将菌株WS3-1鉴定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens).菌株WS3-1发酵液中活性物质在温度为40℃、60℃、80℃以及pH为8～10的条件下,抑菌活性稳定,抑菌率均在80％以上,同时活性物质具有较好的抗紫外线分解能力.以上结果说明解淀粉芽孢杆菌WS3-1是一株具有开发和应用潜力的花生白绢病生防菌株.

为考察磷灰石、石灰和黑麦草对Cd污染土壤的修复效果,通过盆栽试验研究了不同剂量磷灰石(0、6、12、24 g·kg-1风干土,编号为CK、L1、L2、L3)和石灰(1、2、4 g·kg-1风干土,编号为S1、S2、S3)对Cd胁迫下黑麦草生物量、根形态、黑麦草Cd含量、Cd富集量、富集系数、土壤pH、土壤有效态Cd含量等的影响.结果表明,磷灰石、石灰处理(L1,S1除外)显著增加了黑麦草生物量、根长、根表面积、根体积、根尖数、Cd富集量和土壤pH,显著降低了黑麦草Cd含量、Cd富集系数、根平均直径和土壤有效态Cd含量.相关性分析结果表明:除根平均直径为正相关关系外,黑麦草根长、根表面积、根体积、根尖数与土壤有效态Cd含量、黑麦草地上部分及根系Cd含量、Cd富集系数呈显著或极显著负相关关系;除根平均直径为负相关关系外,其他根指标与黑麦草地上部分及根系生物量、Cd富集量呈极显著正相关关系.其中,L3处理黑麦草地上部分及根系生物量达到CK处理(不添加改良剂)的176.0倍和174.4倍;根平均直径相比CK降低了29.4％,根长、根表面积、根体积和根尖数分别为CK处理的20.2、21.0、21.3倍和24.5倍;黑麦草地上部分及根系Cd富集量达到CK处理的89.6倍和100.9倍.研究表明,根形态受土壤有效态Cd含量的影响显著,并可通过影响黑麦草生物量及Cd吸收决定其Cd富集量,施用24 g·kg-1的磷灰石并种植黑麦草能很好地修复Cd污染土壤.

为了获得具有防治根结线虫作用的菌株,采用几丁质平板透明圈初筛和离体拮抗试验复筛的方法,得到一株具有生防潜力的真菌菌株SFC-3.通过形态学特征观察和真菌内转录间隔区序列(Internal transcribed spacer,ITS)分析鉴定,确定菌株SFC-3为棘孢木霉(Trichoderma asperellum),其几丁质酶活为2.07 U/mL.根结线虫虫卵寄生实验和二龄幼虫致死率实验表明:菌株SFC-3对虫卵的寄生率最高达到78.86％,高于SFC-1、SFC-22等其他9株菌,在第7天时对根结线虫虫卵孵化的相对抑制率最高达到96.51％,对二龄幼虫的校正死亡率达到93.37％.通过筛选抗根结线虫菌株并研究了其生防效果,证实了菌株SFC-3有比较优秀的抗根结线虫性能.

为探究引起河南省汝南县花生白绢病的病原种类及其生物学特性,利用形态学和分子生物学方法对分离自汝南县的花生白绢病原真菌进行鉴定,同时研究了病原菌的生物学特性及室内药剂筛选.结果表明,引起汝南县花生白绢病的病原菌为罗氏阿太菌(Athelia rolfsii),其无性态为齐整小核菌(Sclerotium rolfsii).生物学特性研究表明花生白绢病的病原菌生长的最适温度为30℃,最适pH为6.0.该菌能利用供试的碳源、氮源进行营养生长,但在以葡萄糖、麦芽糖或淀粉为唯一碳源和以尿素作为唯一氮源的培养基上均不能产生菌核.菌核的抑制萌发温度为55℃,时间为10 min.室内抗病药毒力测定结果表明,戊唑醇对罗氏阿太菌的毒力最强,EC50值为0.4629 mg/L.

为了探讨新型快速秸秆还田促腐菌剂对小麦秸秆还田在水稻田的施用剂量和促生效果,进行了相关的大田试验.本试验在常规施肥和小麦秸秆粉碎还田的基础上设置了M1(CK),M2(30 kg/hm2),M3(75 kg/hm2)和M4(120 kg/hm2)4个梯度的促腐菌剂施用剂量,研究了不同施用剂量对水稻成产因素以及水稻产量的影响.研究表明,施用新型快速秸秆还田促腐菌剂不仅可以促进秸秆降解,且对每公顷水稻的穗数、穗粒数及产量影响显著.与对照组M1相比,M3(75 kg/hm2)组促产效果最好,其中每公顷穗数为466.35万穗,比对照提高了16.09％;穗粒数为86.03比对照提高了12.12％.在实际产量方面M3组为7510.35 kg/hm2,比对照提高了12.94％.土壤理化性质表明,促腐菌剂显著提高了土壤中碱解氮、有效磷、速效钾的含量,与对照组相比分别提高了93.33％、18.13％和46.93％.该试验评价了施用不同剂量新型快速秸秆还田促腐菌剂对小麦秸秆在水稻田降解及水稻产量的影响,为新型快速秸秆还田促腐菌剂的研发奠定了理论基础.

通过Illumina MiSeq高通量测序技术,对花生根、茎、叶、花不同器官内生细菌16S rRNA的V5～V7可变区进行测序,研究花生内生细菌群落多样性.从花生不同器官内一共获得61396条有效序列和468个OTU(Operational Taxonomic Units).物种分类显示花生内生细菌种类隶属于21个门、43个纲、107个目、177个科和284个属.根部内生细菌优势属为假单胞菌属(Pseudomonas)、慢生根瘤菌属(Bra-dyrhizobium)和魏斯氏菌属(Weissella),相对丰度分别为37.67％、25.13％和7.38％;茎部内生细菌优势属为假单胞菌属(Pseudomonas)和红球菌属(Rhodococcus),相对丰度分别为73.12％和8.88％;叶部内生细菌优势属为假单胞菌属(Pseudomonas)和红球菌属(Rhodococcus),相对丰度分别为78.65％和8.55％;花部内生细菌优势属为假单胞菌属(Pseudomonas),相对丰度为15.15％.PICRUSt功能预测表明,叶部内生细菌中参与调控各种代谢通路的物种丰度最高,茎部和根部次之,花部最低.以上研究结果表明花生内生细菌具有丰富的种群多样性,为今后开发利用花生内生细菌资源奠定了基础.

【目的】利用中国科学院微生物研究所真菌学国家重点实验室分离获得的菌株Trametes hirsuta zlh237,研究生物强化（接种菌株T. hirsuta zlh237发酵液）对污染土壤中3种多环芳烃（PAHs）[Phenanthrene、Pyrene和Benzo[a]pyrene（BaP）]的降解效果,为该菌株在PAHs污染土壤中的应用提供科学依据。【方法】采用高效液相色谱（HPLC）检测7个处理土壤（接种菌株T. hirsuta zlh237发酵液的Phenanthrene、Pyrene和BaP污染土壤分别标记为PheBA、PyrBA和BaPBA,接种灭菌发酵液的污染土壤分别标记为Phe、Pyr和BaP,原始土壤标记为CK）中3种PAHs含量,利用ABTS法检测土壤中漆酶活性,并运用高通量测序技术分析修复后土壤中细菌群落结构的变化。【结果】菌株T. hirsuta zlh237在3种PAHs污染土壤中均能生长,接种菌株发酵液15 d后,3种PAHs均有一定降解,其中BaP降解效果最佳,降解率达33.99%;且菌株T. hirsuta zlh237在3种污染土壤中均能分泌漆酶。高通量测序Alpha多样性指数分析结果表明,污染土壤接种菌株T. hirsuta zlh237发酵液后,Chao1指数和Shannon指数显著增加（P＜0.05）,不同处理土壤样品的Chao1指数和Shannon指数排序均为:PheBA＞PyrBA＞BaPBA＞CK＞Phe＞Pyr＞BaP。Beta多样性的主成分分析（PCA）结果表明,接种菌株T. hirsuta zlh237发酵液能改变污染土壤细菌群落结构组成;在门分类水平上,污染土壤样品中变形菌门（Proteobacteria）为优势门;在属分类水平上,接种菌株T. hirsuta zlh237发酵液的污染土壤样品中鞘氨醇单胞菌属（Sphingomonas）为优势菌属,接种灭菌发酵液的污染土壤Phe和Pyr样品中苯基杆菌属（Phenylobacterium）为优势菌属,而BaP样品中假单胞菌属（Pseudomonas）为优势菌属。【结论】菌株T. hirsuta zlh237发酵液在PAHs污染土壤中能分泌漆酶,对3种PAHs均有一定的降解效果,且能改变污染土壤细菌群落结构组成,在一定程度上对PAHs污染土壤有较好的修复效果。

探讨不同剂量的枯草芽孢杆菌菌剂对小麦生理生化指标的影响,为提高小麦产量提供科学依据.试验采用盆栽试验方式,设7个处理,即每千克土壤中分别添加0(空白对照)、0.5、1、2、3、4 g和5 g不同剂量的枯草芽孢杆菌菌剂,每个处理设4个重复,然后每盆播种50粒小麦种子,自然光照,室温培养20 d后将小麦从盆中取出,检测其幼苗的生理生化指标.结果表明,与不施菌的对照组相比,在土壤中添加不同剂量的枯草芽孢杆菌菌剂对小麦种子的发芽率、株高和根系的发育均有一定程度地促进作用,并能显著增加叶片中叶绿素含量和POD酶活,而对可溶性蛋白的含量影响不大.当施菌剂量为0.5 g/kg时小麦叶片中SOD活性最高,但随着施菌剂量的增加,枯草芽孢杆菌菌剂对叶片中SOD活性反而有所降低;并且小麦叶片中MDA的含量有减少趋势,另外,土壤中氮、磷、钾元素的含量随着土壤中随着施菌剂量的增加而显著提升.因此,施用一定剂量的枯草芽孢杆菌菌剂对小麦各项生理生化指标以及土壤中氮磷钾的含量均有不同程度的促进作用.

In order to find a more efficient, economical, and environmentally friendly chemical fertilizer alternative, we have developed a new type of microbial fertilizer. The reported types of functional microorganisms in biofertilizers are mostly single and concentrated in nitrogen-fixing bacteria and phosphate-solubilizing bacteria. Here we evaluate the effect of the compound microbial fertilizer with several kinds of functional bacteria. A field experiment was conducted with five treatments (no-fertilization control, regular fertilization 600 kg ha−1, compound microbial fertilizer 750 kg ha−1, compound microbial fertilizer 900 kg ha−1, compound microbial fertilizer 1050 kg ha−1). The effects of the compound microbial fertilizer on wheat traits, grain yield, soil physical and chemical properties, and microbial community structure were investigated. The results showed that the compound microbial fertilizer as base fertilizer could not only enhance the contents of soil available phosphorus and available potassium but also enhance the grain yield markedly. The compound microbial fertilizer could affect the microbial community, and the change of the microbial community was more correlated with growth period of wheat. The results established that the compound microbial fertilizer which can reduce part of the amount of chemical fertilizer can enhance wheat yield and the recommended dose of the fertilizer is 750 kg ha−1 in the study area.