TY - JOUR
T1 - Co-aggregation in Azospirillum brasilensense MTCC-125 with other PGPR strains
T2 - Effect of physical and chemical factors and stress endurance ability
AU - Joe, Manoharan Melvin
AU - Jaleel, Cheruth Abdul
AU - Sivakumar, Palanivel Karpagavinayaka
AU - Zhao, Chang Xing
AU - Karthikeyan, Balathandayutham
PY - 2009/9
Y1 - 2009/9
N2 - This work aims at exploring the co-aggregation of Azospirillum brasilense MTCC-125 with other plant growth promoting rhizobacterial (PGPR) strains. The PGPR strains include Azotobacter chroococcum MTCC-446, Azorhizobium caulinodans ORS-571, Bacillus megatherium MTCC-3353 and Pseudomonas fluorescens MTCC-4828. The influence of different physical and chemical factors involved in this phenomenon was investigated. Co-aggregation was found to be dependent on various factors: pH, temperature, inoculation level and growth phase. Treatment with urea, protease and chelating agents such as EDTA (ethylene diamine, tetra acetic acid) and EGTA (ethyl glycol-bis(β-amino ethyl ether) N-N′-tetra acetic acid) was found to inhibit co-aggregation. Sonication was found to increase co-aggregation, while heat treatment has a detrimental effect. The ability of Azospirillum co-aggregates to endure desiccation, heat, osmotic tolerance and osmotic shock and for its survivability in different carrier materials were also evaluated. Among the different combinations, the co-inoculation of Azospirillum MTCC-125 and Azotobacter MTCC-446 exhibited a higher degree of tolerance as compared to the other combinations tested.
AB - This work aims at exploring the co-aggregation of Azospirillum brasilense MTCC-125 with other plant growth promoting rhizobacterial (PGPR) strains. The PGPR strains include Azotobacter chroococcum MTCC-446, Azorhizobium caulinodans ORS-571, Bacillus megatherium MTCC-3353 and Pseudomonas fluorescens MTCC-4828. The influence of different physical and chemical factors involved in this phenomenon was investigated. Co-aggregation was found to be dependent on various factors: pH, temperature, inoculation level and growth phase. Treatment with urea, protease and chelating agents such as EDTA (ethylene diamine, tetra acetic acid) and EGTA (ethyl glycol-bis(β-amino ethyl ether) N-N′-tetra acetic acid) was found to inhibit co-aggregation. Sonication was found to increase co-aggregation, while heat treatment has a detrimental effect. The ability of Azospirillum co-aggregates to endure desiccation, heat, osmotic tolerance and osmotic shock and for its survivability in different carrier materials were also evaluated. Among the different combinations, the co-inoculation of Azospirillum MTCC-125 and Azotobacter MTCC-446 exhibited a higher degree of tolerance as compared to the other combinations tested.
KW - Azospirillum brasilense
KW - Co-aggregation
KW - Plant growth promoting rhizobacteria (PGPR)
KW - Survival
KW - Tolerance
UR - http://www.scopus.com/inward/record.url?scp=67651166627&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=67651166627&partnerID=8YFLogxK
U2 - 10.1016/j.jtice.2009.02.006
DO - 10.1016/j.jtice.2009.02.006
M3 - Article
AN - SCOPUS:67651166627
SN - 1876-1070
VL - 40
SP - 491
EP - 499
JO - Journal of the Taiwan Institute of Chemical Engineers
JF - Journal of the Taiwan Institute of Chemical Engineers
IS - 5
ER -