标题:Application Effect Of Exopolysaccharide ( Eps) Rich, Pgpr Coaggregates On The Enhancement Of Isr Mediated Biocontrol In Groundnut Sclerotium Rolfsii Pathosystem Under Rainfed Condition
摘要:The bioinoculation effect of different bioformulations, viz.,vegetative cell application, co-inoculation and co-aggregates application, of efficient PGPR cells viz., Methylobacterium (MB-5) and Rhizobium sp. (RM-5), together with challenge inoculation of Sclerotium rolfsii on the induction of induced systemic resistance (ISR) in groundnut-Sclerotium rolfsii pathosystem was studied under pot culture condition with groundnut cv.JL-24. It was observed that the application of, Methylobacterium e and Rhizobium, as co-aggregates, positively altered the biochemical and physiological parameters viz., reducing and non-reducing sugars, total and OD phenol content and defense enzymes activities, such as, peroxidase (PO) and polyphenol oxidase (PPO), of groundnut plant to the highest level followed by co-inoculation and single strain inoculation treatment. The application of PGPR cells, as co-aggregates, was found to augment the total and OD phenol content and defense enzyme activities, such as, PO and PPO content of groundnut plant to a higher level whereas a reduction in reducing and non-reducing sugar level was recorded, which ultimately lead to a reduction in Sclerotium rolfsii incidence in rainfed groundnut. It has been postulated that the EPS biosynthesis of PGPR cells during coaggregation processes, might act as an elicitor for the enhancement of ISR in groundnut-Sclerotium rolfsii pathosystem whereas application the vegetative cell and co-inoculation formulations, without any involvement of EPS, responded poorly for the enhancement of ISR in the same pathosystem. This is the first comprehensive report on the positive role of bacterial EPS, as a determinant of ISR, in groundnut-Sclerotium rolfsii pathosytem.
关键词:pgpr; microbial coaggregates;physiological and biological parameters;eps-isr;sclerotium rolfsii;rainfed groundnut