Comparative Study of Bacillus-Based Plant Biofertilizers: A Proposed Index
Abstract
:Simple Summary
Abstract
1. Introduction
2. Materials and Methods
2.1. Microorganisms, Media, and Culture Conditions
2.2. Isolation of Drought-Protecting Bacterial Strains
2.3. Sporulation Test
2.4. Optical and Electronic Microscopy
2.5. Monitoring of Plant Growth
2.6. Plant-Growth Conditions, Bacterial Inoculation, and Plant Sampling
2.7. Phosphate Solubilization Test
2.8. Potassium Solubilization Assay
2.9. Siderophore Production Assay
2.10. Quantification of Phytohormones: Indole Acetic Acid, Indole Butyric Acid, and Gibberellins
2.11. Determination Urea Hydrolysis
2.12. Antagonism and Antibiosis Assays
- Antagonism
- Antibiosis
2.13. Extraction of Nucleic Acids and Next-Generation Sequencing
2.14. Genome Sequencing
2.15. Statistical Analysis
3. Results
3.1. Isolation of a Collection of Drought-Protecting Spore-Forming Strains
3.2. Taxonomic Affiliation and Genome Sequence of Bacillus sp. A6
3.3. Plant-Growth-Promoting Rizhobacteria Traits of B. velezensis A6 and Their Closest Commercial Strains
3.4. Drought Protection and Plant-Growth Promotion of Pepper Plants
3.5. Biofungicidal Activity of the Bacterial Strains
3.6. Phosphate and Potassium Salt Solubilization
3.7. Siderophore Production
3.8. Urea Hydrolysis
3.9. Quantification of Phytohormones: Indole Acetic Acid, Indole Butyric Acid, and Gibberellic Acid
3.10. Agricultural Protection against Stress Index (APSI)
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Strain | Role in This Study | Reference |
---|---|---|
Pseudomonas putida KT2440 | PGPR Spore staining | [4] |
Escherichia coli OP50 | PGPR | [21] |
Microbacterium sp. 3J1 | PGPR | [4] |
Proteus sp. S47 | Siderophore negative control | [22] |
Bacillus amyloliquefaciens D747 | PGPR and fungicides | [15] |
Bacillus amyloliquefaciens subsp. amyloliquefaciens Fukumoto DSM7 | PGPR and fungicides | [13,14] |
Bacillus velezensis FZB42 | PGPR and fungicides | [16] |
Bacillus velezensis A6 | PGPR and fungicides | This study |
Bacillus subtilis CECT39 | Spore staining | [20] |
Number | Accession Number | Species | % Similarity |
---|---|---|---|
1 | AJVF01000044→ 16S: MW578390 | B. siamensis KCTC 13613(T) | 99.93 |
2 | AY603658 | B. velezensis CR-502(T) | 99.92 |
3 | ABQL01000001→ 16S: MK559753 | B. subtilis subsp. subtilis NCIB 3610(T) | 99.78 |
4 | FN597644→ 16S: AY055225 | B. amyloliquefaciens DSM 7(T) | 99.70 |
5 | AY820954 | B. nematocida B-16(T) | 99.70 |
6 | LSAZ01000028→ 16S: NR_151897 | B. nakamurai NRRL B-41091(T) | 99.63 |
7 | AYTO01000043 | B. tequilensis KCTC 13622(T) | 99.55 |
8 | MK462260 | TE3(T) | 99.55 |
9 | AMXN01000021 | B. KCTC 13429(T) | 99.55 |
10 | MN536904 | B. stercoris JCM 30051(T) | 99.55 |
11 | JH600273→ NZ_JH600276 | B. DV1-F-3(T) | 99.48 |
12 | JABUXO010000041→ 16S: MT554518 | B. rugosus SPB7(T) | 99.48 |
13 | AB021181 | B. atrophaeus JCM 9070(T) | 99.40 |
14 | LPVF01000003→ 16S: MN840041 | B. halotolerans ATCC 25096(T) | 99.40 |
15 | CP002905→ 16S: NR_024931 | B. spizizenii NRRL B-23049(T) | 99.40 |
16 | JH600280→ 16S: NZ_AYTL01000035 | B. mojavensis RO-H-1(T) | 99.33 |
17 | LECW01000063 | B. glycinifermentans GO-13(T) | 98.28 |
18 | KY694465 | B. paralicheniformis KJ-16(T) | 98.20 |
19 | AUQZ01000032→16S: JF802181 | B. sp. NSP9.1 | 98.05 |
20 | AE017333→ 16S: LR594217 | B. licheniformis ATCC 14580(T) | 97.98 |
21 | MRBL01000076→ NR_157609 | B. haynesii NRRL B-41327(T) | 97.90 |
22 | AYTN01000016 * | B. sonorensis NBRC 101234(T) | 97.75 |
23 | MRBK01000096→ NR_157608 | B. swezeyi NRRL B-41294(T) | 97.75 |
24 | AJ831843 | B. aerius 24K(T) | 97.37 |
25 | ASJC01000029 | B. altitudinis 41KF2b(T) | 97.30 |
26 | AMSH01000114 | B. xiamenensis HYC-10(T) | 97.22 |
27 | LJIY01000004→ NZ_LJIY01000031 | Psychrobacillus sp. FJAT-21963 | 97.22 |
28 | ASJD01000027→ 16S: MK849613 | B. safensis subsp. safensis FO-36b(T) | 97.07 |
29 | KY990920 | B. safensis subsp. osmophilus BC09(T) | 97.07 |
30 | ABRX01000007→ 16S: MKZN01000032 | B. pumilus ATCC 7061(T) | 97.00 |
31 | JOTP01000061→ 16S: MZ066819 | B. zhangzhouensis DW5-4(T) | 97.00 |
32 | JX680098→ 16S: MW228046 | B. australimaris NH7I_1(T) | 96.92 |
33 | MKZN01000032 | B. pumilus GM3FR BACPU | 96.77 |
34 | LC367333 | B. salacetis SKP7-4(T) | 96.18 |
35 | KF548480 | B. oryzaecorticis R1(T) | 96.17 |
36 | ABCF01000001 | B. sp. SG-1 1101501000768 | 96.10 |
Max Score | A6 | FZB42 | DSM7 | D747 | |
---|---|---|---|---|---|
Root Length (PGPR) | 5 | 5 | 3.75 | 3.75 | 3.75 |
Stem Length (PGPR) | 5 | 5 | 5 | 3.75 | 2.5 |
Dry Weight (PGPR) | 5 | 5 | 5 | 2.5 | 3.75 |
RWC (PGPR) | 5 | 5 | 5 | 5 | 5 |
RWC (Drought) | 9 | 9 | 6.75 | 6.75 | 6.75 |
Root Length (Drought) | 9 | 9 | 6.75 | 6.75 | 4.5 |
Dry Weight (Drought) | 9 | 9 | 6.75 | 6.75 | 6.75 |
Antagonism B. cinerea | 7 | 7 | 7 | 1.75 | 7 |
Antagonism F. oxysporum | 7 | 5.95 | 3.5 | 0 | 5.25 |
Antibiosis B. cinerea | 7 | 3.5 | 3.5 | 1.75 | 3.5 |
Antibiosis F. oxysporum | 7 | 3.5 | 1.75 | 1.75 | 3.5 |
Siderophores | 4 | 4 | 4 | 4 | 4 |
Phosphate Solubilization | 4 | 1 | 2 | 4 | 2 |
Potassium Solubilization | 4 | 4 | 4 | 4 | 4 |
AIA Production | 3 | 0.75 | 0.75 | 3 | 0.75 |
IBA Production | 3 | 2.25 | 2.25 | 3 | 2.25 |
GB Production | 3 | 0 | 0 | 3 | 0 |
Urea Hydrolysis | 4 | 0 | 0 | 0 | |
Total Maximum Score | 100 | 78.95 | 67.75 | 61.5 | 65.25 |
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Barros-Rodríguez, A.; Pacheco, P.; Peñas-Corte, M.; Fernández-González, A.J.; Cobo-Díaz, J.F.; Enrique-Cruz, Y.; Manzanera, M. Comparative Study of Bacillus-Based Plant Biofertilizers: A Proposed Index. Biology 2024, 13, 668. https://doi.org/10.3390/biology13090668
Barros-Rodríguez A, Pacheco P, Peñas-Corte M, Fernández-González AJ, Cobo-Díaz JF, Enrique-Cruz Y, Manzanera M. Comparative Study of Bacillus-Based Plant Biofertilizers: A Proposed Index. Biology. 2024; 13(9):668. https://doi.org/10.3390/biology13090668
Chicago/Turabian StyleBarros-Rodríguez, Adoración, Pamela Pacheco, María Peñas-Corte, Antonio J. Fernández-González, José F. Cobo-Díaz, Yasmira Enrique-Cruz, and Maximino Manzanera. 2024. "Comparative Study of Bacillus-Based Plant Biofertilizers: A Proposed Index" Biology 13, no. 9: 668. https://doi.org/10.3390/biology13090668