TY - JOUR
T1 - Characterization of mineral phosphate-solubilizing bacteria for enhanced sunflower growth and yield-attributing traits
AU - Shahid, Muhammad
AU - Hameed, Sohail
AU - Tariq, Mohsin
AU - Zafar, Mohsin
AU - Ali, Amanat
AU - Ahmad, Naveed
N1 - Publisher Copyright:
© 2014, Springer-Verlag Berlin Heidelberg and the University of Milan.
PY - 2015/9/11
Y1 - 2015/9/11
N2 - Nineteen isolates of rhizobacteria associated with sunflower (Helianthus annuus L.), collected from various locations in Pakistan, were screened for phosphate solubilization and indole-3-acetic acid (IAA) production. Two potential phosphate-solubilizing bacterial isolates with substantial IAA biosynthesis capacity, Ps-5 and Ss-2, were selected for further study. Based on 16S rRNA gene sequence analysis, isolate Ps-5 was identified as Bacillus sp. and Ss-2 as Alcaligenes faecalis. Both strains were found to be metabolically diverse in terms of the number and amount of different carbon substrates they utilized in the BIOLOG GN2/GP2 microplate assay. High-performance liquid chromatography analysis of the culture supernatant confirmed that Bacillus sp. Ps-5 produced considerable amounts of both lactic and tartaric acids, while A. faecalis Ss-2 secreted only lactic acid. There was a strong positive correlation between phosphate solubilization and organic acid production by both strains. Following inoculation, strain Ps-5 and Ss-2 were found to be good root colonizers and significantly (P ≤ 0.05) increased sunflower growth and phosphorus (P) uptake. However, inoculation had a non-significant (P ≤ 0.05) effect on sunflower yield parameters, including oil contents. Based on these results, we conclude that Ps-5 and Ss-2 are potent plant growth-promoting rhizobacteria strains with the ability to supplement the P requirements of sunflower crops. Further field inoculation studies are needed before these strains can be recommended as bio-inoculants. To the best of our knowledge, this is first report on the association and phytobeneficial potential of A. faecalis with sunflower.
AB - Nineteen isolates of rhizobacteria associated with sunflower (Helianthus annuus L.), collected from various locations in Pakistan, were screened for phosphate solubilization and indole-3-acetic acid (IAA) production. Two potential phosphate-solubilizing bacterial isolates with substantial IAA biosynthesis capacity, Ps-5 and Ss-2, were selected for further study. Based on 16S rRNA gene sequence analysis, isolate Ps-5 was identified as Bacillus sp. and Ss-2 as Alcaligenes faecalis. Both strains were found to be metabolically diverse in terms of the number and amount of different carbon substrates they utilized in the BIOLOG GN2/GP2 microplate assay. High-performance liquid chromatography analysis of the culture supernatant confirmed that Bacillus sp. Ps-5 produced considerable amounts of both lactic and tartaric acids, while A. faecalis Ss-2 secreted only lactic acid. There was a strong positive correlation between phosphate solubilization and organic acid production by both strains. Following inoculation, strain Ps-5 and Ss-2 were found to be good root colonizers and significantly (P ≤ 0.05) increased sunflower growth and phosphorus (P) uptake. However, inoculation had a non-significant (P ≤ 0.05) effect on sunflower yield parameters, including oil contents. Based on these results, we conclude that Ps-5 and Ss-2 are potent plant growth-promoting rhizobacteria strains with the ability to supplement the P requirements of sunflower crops. Further field inoculation studies are needed before these strains can be recommended as bio-inoculants. To the best of our knowledge, this is first report on the association and phytobeneficial potential of A. faecalis with sunflower.
KW - Biolog
KW - IAA production
KW - Oil content
KW - Phosphate-solubilizing bacteria
KW - Sunflower
KW - Transmission electron microscopy
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U2 - 10.1007/s13213-014-0991-z
DO - 10.1007/s13213-014-0991-z
M3 - Article
AN - SCOPUS:84938982217
SN - 1590-4261
VL - 65
SP - 1525
EP - 1536
JO - Annals of Microbiology
JF - Annals of Microbiology
IS - 3
ER -