Use of Cyanobacteria for Controlling Flax Seedling Blight

Abstract

Cyanobacteria are one of important groups of prokaryotes due to their effects on growth and development of plants and its role in biological control of phytopathogenic fungi such as : Fusarium oxysporum and Rhizoctonia solani on flax by producing various biologically active substances . In the present study , fourteen cyanobacterial strains were isolated from rice rhizosphere in kafr El–sheikh (k) ( North Delta Region ) and El- Dakahliya (D) ( East Delta Region ) . Only five cyanobacterial strains showed antagonistic effects against the both pathogenic fungi and were indentified as Nostoc muscorum k , Anabaena oryzae D , Anabaena oryzae k , Nostoc pruniforme D and Oscillatoria brevis D. The strains were analysed for phosphate solubilization , production of IAA , ammonia , HCN , production of some enzymes , and effect of their filterates on seed germination of flax seeds . Flax seeds treated with cyanobacterial filtrates germinated faster and produced higher seedlings compared with the nontreated ones .