Isolation and Identification of Potential Phosphate Solubilizing Bacteria from the Rhizoplane of Oryza sativa L. cv. BR29 of Bangladesh

2007 ◽  
Vol 62 (1-2) ◽  
pp. 103-110 ◽  
Author(s):  
Md. Tofazzal Islam ◽  
Abhinandan Deora ◽  
Yasuyuki Hashidoko ◽  
Atiqur Rahman ◽  
Toshiaki Ito ◽  
...  

A total of 30 bacteria were isolated from the rhizoplane of rice cv. BR29 cultivated in Mymensingh, Bangladesh and from the seedlings obtained from surface-sterilized seeds of BR29. Upon screening, 6 isolates showed varying levels of phosphate solubilizing activity in both agar plate and broth assays using National Botanical Research Institute’s phosphate medium. The bacterial isolates were identified based on their phenotypic and 16S rRNA genes sequencing data as Acinetobacter sp. BR-12, Klebsiella sp. BR-15, Acinetobacter sp. BR-25, Enterobacter sp. BR-26, Microbacterium sp. BRS-1 and Pseudomonas sp. BRS-2. The BR-25 exhibited highest phosphate solubilizing activity followed by BR-15. They grew rapidly in the liquid medium at pH 5 and 7 but almost no growth occurred at pH 3. The pH value of the culture medium was decreased with bacterial growth suggesting that they might secrete organic acids to solubilize insoluble phosphorus. Scanning electron microscope analysis of two-week-old rice seedlings germinated from seeds previously inoculated with BR-25 and BR-15 revealed dense colonization at the root surfaces presumably using fimbriae on the bacterial cells.

2016 ◽  
Vol 8 (1) ◽  
pp. 93-96 ◽  
Author(s):  
Anurag Yadav ◽  
Kusum Yadav ◽  
Anupam Vashistha

A study was designed to screen and analyze the efficient phosphate solubilizing bacteria (PSBs) from wheat rhizosphere. Five biovars of Pseudomonas fluorescens (PSM1, PSM2, PSM3, PSM4 and PSM5) were isolated from wheat rhizosphere and Bacillus megaterium MTCC 8755 procured from microbial type culture collection (MTCC) Chandigarh, India. The P. fluorescens biovar PSM1 was observed to be most efficient phosphate solubilizer. Inoculation of P. fluorescens PSM1 and B. megaterium MTCC 8755, alone and in combination, caused the highest phosphate solubilization at pH 5. At this pH, maximum phosphate solubilization was observed with B. megaterium MTCC 8755 inoculation (8.2 mg mL-1) on sixth day of incubation with P. fluorescens PSM1 (8 mg mL-1) on seventh day of incubation and with dual bacterial treatment (10.5 mg mL-1) on the fourth day of incubation. A correlation coefficient of linear regression equation of phosphate solubilization with pH indicated that pH value of the medium was directly correlated with tricalcium phosphate solubilization. The study will help in choosing soil pH specific PSB inoculant for optimizing plant growth.


2021 ◽  
Vol 12 ◽  
Author(s):  
Juan Zhong ◽  
Xuewu Hu ◽  
Xingyu Liu ◽  
Xinglan Cui ◽  
Ying Lv ◽  
...  

The remediation of uranium (U) through phosphate-solubilizing bacteria (PSB) is an emerging technique as well as an interesting phenomenon for transforming mobile U into stable minerals in the environment. While studies are well needed for in-depth understanding of the mechanism of U(VI) immobilization by PSB. In this study, two PSB were isolated from a U-tailing repository site. These bacterial strains (ZJ-1 and ZJ-3) were identified as Bacillus spp. by the sequence analysis of 16S ribosomal RNA (rRNA) genes. Incubation of PSB in liquid medium showed that the isolate ZJ-3 could solubilize more than 230 mg L–1 P from glycerol-3-phosphate and simultaneously removed over 70% of 50 mg L–1 U(VI) within 1 h. During this process, the rapid appearance of yellow precipitates was observed. The microscopic and spectroscopic analysis demonstrated that the precipitates were associated with U-phosphate compound in the form of saleeite-like substances. Besides, scanning electron microscopy coupled with energy-dispersive X-ray (SEM-EDS) and Fourier transform infrared spectroscopy (FTIR) analysis of the precipitates confirmed that the extracellular polymeric substances (EPS) might also play a key role in U sequestration. Furthermore, SEM and FTIR analysis revealed that part of U(VI) was adsorbed on the bacterial surface through cellular phosphate, hydroxy, carboxyl, and amide groups. This study provides new insights into the synergistic strategies enhancing U immobilization rates by Bacillus spp. that uses glycerol-3-phosphate as the phosphorus source, the process of which contributes to harmful pollutant biodegradation.


2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Mohammad Bagher Javadi Nobandegani ◽  
Halimi Mohd Saud ◽  
Wong Mui Yun

Phosphate solubilizing bacteria (PSB) can convert insoluble form of phosphorous to an available form. Applications of PSB as inoculants increase the phosphorus uptake by plant in the field. In this study, isolation and precise identification of PSB were carried out in Malaysian (Serdang) oil palm field (University Putra Malaysia). Identification and phylogenetic analysis of 8 better isolates were carried out by 16S rRNA gene sequencing in which as a result five isolates belong to the Beta subdivision ofProteobacteria, one isolate was related to the Gama subdivision ofProteobacteria, and two isolates were related to theFirmicutes. Bacterial isolates of 6upmr, 2upmr, 19upmnr, 10upmr, and 24upmr were identified asAlcaligenes faecalis. Also, bacterial isolates of 20upmnr and 17upmnr were identified asBacillus cereusandVagococcus carniphilus, respectively, and bacterial isolates of 31upmr were identified asSerratia plymuthica. Molecular identification and characterization of oil palm strains as the specific phosphate solubilizer can reduce the time and cost of producing effective inoculate (biofertilizer) in an oil palm field.


2019 ◽  
Vol 60 (5) ◽  
pp. 985-995
Author(s):  
Yusur Ramzi ◽  
Hutaf A. A. Alsalim

Sixteen soil samples were collected from wheat, barley and yellow corn rhizosphere in Abu-Ghraib, Aqraqof, Latifieh,Tarmiah, Jadriya and  of Agriculture in Baghdad university/ Baghdad city. The results found nine phosphate solubilizing bacteria (PSB) isolates (Y1, Y2, Y3, Y4, Y5, Y6, Y7, Y8, Y9), formed clear zones on National Botanical Research Institute's (NBRIP) agar. The solubility index (SI) of PSB isolates ranged from 2.00 to 3.66. Y4 have the highest SI (3.66) followed by Y3 and Y6 (3.33). Phosphate solubilization abilities varying from (20.10-39.00 μg.ml-1), Y4 was the highest (39.00 μg.ml-1) followed by Y3 (37.00μg.ml-1). The results of hydrolytic enzymes production showed that almost all nine isolates are able to produce protease and pectinase, while Y1 and Y2 showed negative results in cellulase production. Maximum ability for hydrogen cyanide (HCN) and indole acetic acid (IAA) production were showed byY3 and Y4 isolates. The isolate Y4 was found to be the most efficient isolate, so it was selected identified as Bacillus cereus using biochemical tests confirmed by VITEC 2 compact system. The results of High performance liquid chromatography (HPLC) revealed that Bacillus cereus produce oxalic acid (2.996), citric acid (9.117) and malic acid (3.734). Bacillus cereus (Y4) enhanced the growth of mung bean plants. A significant increase in branches number (12.33), plant length (83.0cm), fresh weight (27.25 g) and dry weight (1.427g) were obtained compared with control treatments. The main objective of this study is to isolate PSB and evaluate their roles in plant growth promotion. The results showed the high phosphate solubilization efficiency of PSB isolates and the identified isolates was found to be good enough for plant growth promoting.


2018 ◽  
pp. 1720-1724 ◽  
Author(s):  
Shahin Mahmud ◽  
K. H. M. Nazmul Hussain Nazir ◽  
Md. Tanvir Rahman

Aim: The present study was carried out to determine the prevalence and molecular detection of fluoroquinolone-resistant Escherichia coli carrying qnrA and qnrS genes in healthy broiler chickens in Mymensingh, Bangladesh, and also to identify the genes responsible for such resistance. Materials and Methods: A total of 65 cloacal swabs were collected from apparently healthy chickens of 0-14 days (n=23) and 15-35 days (n=42) old. The samples were cultured onto Eosin Methylene Blue Agar, and the isolation and identification of the E. coli were performed based on morphology, cultural, staining, and biochemical properties followed by polymerase chain reaction (PCR) targeting E. coli 16S rRNA genes. The isolates were subjected to antimicrobial susceptibility test against five commonly used antibiotics under fluoroquinolone (quinolone) group, namely gatifloxacin, levofloxacin, moxifloxacin, ofloxacin, and pefloxacin by disk diffusion method. Detection of qnrA and qnrS genes was performed by PCR. Results: Among the 65 cloacal samples, 54 (83.08%) were found to be positive for E. coli. Antibiotic sensitivity test revealed that, of these 54 isolates, 18 (33.33%) were found to be resistant to at least one fluoroquinolone antibiotic. The highest resistance was observed against pefloxacin (61.11%). By PCR, of 18 E. coli resistant to fluoroquinolone, 13 (72.22%) were found to be positive for the presence of qnrS. None of the isolates were found positive for qnrA. Conclusion: Fluoroquinolone-resistant E. coli harboring qnrS genes is highly prevalent in apparently healthy broiler chickens and possesses a potential threat to human health.


BioResources ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 2560-2578 ◽  
Author(s):  
Ying-Ying Wang ◽  
Pei-Shan Li ◽  
Bi-Xian Zhang ◽  
Yan-Ping Wang ◽  
Jing Meng ◽  
...  

Phosphate-solubilizing microorganisms have been considered as a novel alternative approach to provide phosphate fertilizers that promote plant growth. In this study, three strains were isolated and identified as Penicillium oxalicum FJG21, Penicillium oxalicum FJQ5, and Bacillus subtilis BPM12, with a relatively high phosphate-solubilizing activity. Various phosphate sources were investigated, and Ca3(PO4)2 was identified as the effective phosphate source. Factors governing the phosphate-solubilizing activity of the strains included carbon and nitrogen sources, initial pH, and fermentation time. A high soluble phosphorus content was achieved with 529.0 μg·mL-1, 514.0 μg·mL-1, and 330.7 μg·mL-1 for Penicillium oxalicum FJG21, Penicillium oxalicum FJQ5, and Bacillus subtilis BPM12, respectively. An inverse correlation of the quantity of soluble phosphorus content and the pH value of the medium was observed. In addition, Bacillus subtilis BPM12 displayed a prominent capability of producing indole acetic acid. Penicillium oxalicum FJG21 and Penicillium oxalicum FJQ5 exhibited high cellulase activities. These phosphate-solubilizing microorganisms with good phosphate-solubilizing capability and growth-promoting ability are the promising strains for agricultural utilization.


2018 ◽  
Vol 45 (3) ◽  
pp. 255
Author(s):  
Pitri Ratna Asih ◽  
Memen Surahman ◽  
Dan Giyanto

Increased productivity of maize can be done with the use of high quality seeds from improved varieties such as hybrid seed. The objectives of this study were Increasing productivity of maize female parent is important in order to reduce the price of hybrid seed. The objectives of this study were to determine the nitrogen fixing bacteria compatible with phosphate solubilizing bacteria (PSB), and using those bacteria to increase physiological seed quality and seedling growth of maize female parent. The research consisted of laboratory and field experiments. Laboratory experiment for the isolation and identification of rhizobacteria resulted in 25 Azotobacter and 29 Actinomycetes non-pathogenic isolates capable of fixing nitrogen and PSB selected for compatibility tests were AB3, B28, P12, P14, P24, and P31. The compatibility test showed 25 pairs of BPF with Azotobacter and 16 pairs of BPF with Actinomycetes were mutually compatible. The BPF pair with Azotobacter or Actinomycetes P24-AzL7, P24-AzL9, B28-AcCKB4, P24-AcCKB9, P24-AcCKB20, and P24-AcCKW5 were able to increase the vigor index of hybrid maize female parent seed. Field experiment was arranged in a split plot design with three replications. The main plot was dosage of N-P fertilizer (0%, 25%, 50%, 75%, and 100% of recommendation dosage), and the subplot was 12 rhizobacteria treatments selected from 25 compatible pairs of BPF with Azotobacter and 16 pairs of BPF with Actinomycetes and 1 control. The application of compatible pairs of bacteria had a significant effect on plant height, the number of leaves at 3 and 4 weeks after planting and plant dry weight. However, the best treatment i.e. B28-AcCKB4 was not significantly different with the nutrient broth treatment (as control).<br /><br /><br />


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