Effect of PGPR on catalase activity of Indian mustard under saline stress

Abstract

Plant Growth Promoting Rhizobacteria (PGPR) plays an important role in agricultural systems, especially as
biofertilizer. Inoculation of plant material with PGPR can protect plants against salt stress through an increase in
plant growth parameters and the regulation of ion concentration and antioxidant enzymes. Salinity produces oxidative
stress by altering the general metabolic processes and enzymatic activities and enhanced occurrence of damaging
toxic molecule i.e. reactive oxygen species (ROS). Plants can run away the damaging effects of reactive oxygen
species by developing a physiologically powerful defence system together with antioxidant enzymes like CAT, POD
and SOD. Catalase, which is involved in the degradation of H2O2 into water and oxygen, is the major H2O2
scavenging enzyme in all-aerobic organisms. Catalase is critical for maintaining the redox balance during oxidative
stress and functions as a cellular sink for H2O2. Microbial inoculation to alleviate salinity stress could provide an
innovative and cost-effective alternative to overcome salinity stress in soils. The objective of the present study was to
evaluate the H2O2 scavenging effects of beneficial bacterial strains of Bacillus species under saline stress in three
different varieties of Indian mustard.