The potential for using cyanobacteria (blue-green algae) and algae in the biological control of plant pathogenic bacteria and fungi

Abstract

Cyanobacteria (blue-green algae) and eukaryote algae occur in freshwater, marine, and terrestrial (soil) habitats. In fact, these microorganisms comprise most of the world's biomass. Although the cyanobacteria are mostly photoautotrophic, some are facultative heterotrophs, capable of growing on certain substrates in darkness. Also, some are non-phototrophic and hence, are obligate heterotrophs. A number of cyanobacteria and eukaryote algae, particularly macroalgae, produce various, biologically active compounds. These include antibiotics which in laboratory tests inhibited bacteria and fungi that incite diseases of humans. In addition, the following fungi which are of interest to plant pathologists, were inhibited in vitro by substances produced by various cyanobacteria: The saprophytes Chaetomium globosum, Cunninghamella blakesleeana, and Aspergillus oryzae, and the plant pathogens Rhizoctonia solani and Sclerotinia sclerotiorum. Extracts from seaweeds (macroalgae) sprayed on plants have been reported to reduce the incidence of Botrytis cinerea (gray mold) on strawberries, Erysiphe polygoni (powdery mildew) on turnips, and damping-off of tomato seedlings. Because many cyanobacteria and algae produce a large number of antibacterial and antifungal materials, are almost never a threat to the environment, and many can be grown in quantity in mass culture, they are suitable candidates for exploitation as biocontrol agents of plant pathogenic bacteria and fungi. Much additional work remains to be done however, to thoroughly evaluate cyanobacteria and algae and their products for this role.

Algal polysaccharides as source of plant resistance inducers

“…In this context, macroalgae show a great potential for generation of new agricultural technologies, attested by the success of already commercialized algae derived products (Kulik, 1995;Stadnik & Paulert, 2008;Craige, 2011).…”

Salt stress enhancement of antioxidant and antiviral efficiency of Spirulina platensis

“…Some Spirulina species exhibit antibacterial (Ozdemir et al, 2004), antiplatelet (Hsiao et al, 2005), antihepatoxic (Mohan et al, 2006) and antiviral activities (HernandezCorona et al, 2002). Spirulina as many other cyanobacteria species have the potential to produce a large number of antimicrobial substances, so they are considered as suitable candidates for exploitation as biocontrol agents of plant pathogenic bacteria and fungi (Kulik, 1995).…”

“…Some Spirulina species exhibit antibacterial (Ozdemir et al, 2004), antiplatelet (Hsiao et al, 2005), antihepatoxic (Mohan et al, 2006) and antiviral activities (HernandezCorona et al, 2002). Spirulina as many other cyanobacteria species have the potential to produce a large number of antimicrobial substances, so they are considered as suitable candidates for exploitation as biocontrol agents of plant pathogenic bacteria and fungi (Kulik, 1995).Salinity represents one of the most important factors exerting stress injury on the growth and metabolism of plants. Salt stress causes an imbalance of the cellular ions resulting in ion toxicity and osmotic stress, leading to retardation of growth either directly by salt or indirectly by oxidative stress induced by reactive oxygen species (ROS).…”

Characterization of the Biocidal Spectrum of Extracellular Filtrates of Microcystis aeruginosa

“…4) in the inhibition of the fungus. The presence of anti-fungal compounds has been reported in a few cyanobacterial genera [6,7,28,29].…”