Influence of cyanobacterial biofertilizer on the response of zea mays plant to cadmium-stress

Abstract

CADMIUM (Cd) pollution is a thoughtful problem that alters crop yield and agricultural soils worldwide. Cyanobacteria are emerging candidates as eco-friendly biofertilizers. The present study evaluates the capability of super blue green biofertilizer (cyanobacteria biofertilizer (CB); Nostoc sp. and Anabaena sp.) to alleviate the Cd toxicity on 21 d-old Zea mays plants (applied as 2 and 10mM CdSO4 ). Application of CB significantly improved maize growth and reduced Cd-accumulation. Cadmium-induced oxidative stress indicated by increment of malondialdehyde (MDA), H2 O2 contents and electrolyte leakage (EL) was diminished upon application of CB. Cd-stress significantly induced L-phenylalanine ammonia-lyase (PAL) specific activity and phenolics accumulation in the leaves and roots of maize plants. The results revealed that Cd-stress markedly enhanced GSH/GSSG ratio, gltuthione reductase (GR), superoxide dismutase (SOD) and catalase (CAT) specific activities, while it decreased that of ascorbate peroxidase (APx) and guaiacol peroxidase (GPx) and insignificantly increased polyphenol oxidase (PPO). The isozyme pattern of peroxidase was changed upon Cd-exposure. CB application significantly reduced both of the Cd-induced accumulated phenolics content and reduced glutathione (GSH) while it increased total glutathione (TG). CB application significantly induced all tested antioxidant enzymes. The data revealed that CB application could reduce Cd toxicity in maize plants.