Biocontrol efficacy and plant growth promoting activity of Bacillus altitudinis isolated from Darjeeling hills, India.

A total of 18 bacterial isolates were obtained from the rhizosphere of Sechium edule growing in the lower foothills of Darjeeling, India. The bacterial isolates were tested for PGPR traits in vitro such as phosphate solubilization, HCN, siderophore, IAA, chitinase, protease production as well as inhibition of pthytopathogens. Of all the bacterial isolates, one bacterium designated as BRHS/S-73 was found to possess all the tested characters which was identified on the basis of 16S rRNA gene sequence analysis as Bacillus altitudinis and was selected for in vivo studies. A significant improvement in growth measured in terms of increase in root length, shoot length, and increase in root and shoot biomass was observed when seeds of Vigna radiata, Cicer arietinum, and Glycine max were bacterized prior to sowing in field condition. Besides, the bacterium could also solubilize soil phosphate. Apart form growth promotion, root rot disease of Vigna radiata caused by Thanatephorus cucumeris was also significantly reduced by 74% when the bacterium was applied to the rhizosphere prior to pathogen challenge. The biocontrol efficacy of the bacterium was found to be 66.6% even after 30 days of pathogen inoculation. Activities of key defense related enzymes such as phenylalanine ammonia lyase, peroxidase, β-1,3-glucanase, and chitinase in both roots and leaves of treated plants were also enhanced. Results clearly suggest that B. altitudinis (BRHS/S-73) is a potential PGPR which can be used as efficient microorganism for enhancement of plant growth and suppression of fungal disease.

Sunar K ，Dey P ，Chakraborty U ，Chakraborty B ... -  《-》

Plant growth promoting potential of bacteria isolated on N free media from rhizosphere of Cassia occidentalis.

Arun B ，Gopinath B ，Sharma S 《-》

Evaluation of Ochrobactrum anthropi TRS-2 and its talc based formulation for enhancement of growth of tea plants and management of brown root rot disease.

Chakraborty U ，Chakraborty BN ，Basnet M ，Chakraborty AP ... -  《-》

Growth promotion and yield enhancement of peanut (Arachis hypogaea L.) by application of plant growth-promoting rhizobacteria.

Dey R ，Pal KK ，Bhatt DM ，Chauhan SM ... -  《MICROBIOLOGICAL RESEARCH》

Screening of PGPR from saline desert of Kutch: growth promotion in Arachis hypogea by Bacillus licheniformis A2.

Rhizosphere of a halotolerant plant Suaeda fruticosa from saline desert of Little Rann of Kutch, Gujarat (India) was explored for isolation of PGPR form the rare ecological niche having4.33% salinity. Total 85 isolates from the rhizosphere belonging to different species were isolated. Out of 85 isolates, 23 could solubilize phosphate and 11 isolates produced IAA. Seven isolates showed both the traits of phosphate solubilization and IAA production. All isolates which showed either of IAA production or phosphate solubilization or both were further screened for other PGP traits like production of ammonia, siderophore, chitinase, HCN and assessment of their antifungal activity. Out of all the screened isolates, Bacillus licheniformis strain A2 showed most prominent PGP traits in vitro and it was tested in vivo for growth promotion of Groundnut (Arachis hypogaea) under saline soil condition. In presence of soil supplemented with 50 mM NaCl, B. licheniformis treated plants showed increase in fresh biomass, total length and root length by 28%, 24% and 17% and in absence of NaCl it was 43%, 31% and 39% respectively.

Goswami D ，Dhandhukia P ，Patel P ，Thakker JN ... -  《-》