Microorganisms in biocontrol of plant pathogens: toxic effects on experimental rate

Beneficial microorganisms using biocontrol agents to reduce the use of unsafe chemical fungicides, give a potent alternative to control plant diseases and is a significant part of sustainable agriculture. Our previous study of a advantage of using biological control showed that biologically, biochemistry and physiology of production of antifungal substances are well documented. Therefore, the potentiality and toxic effects of some beneficial microorganisms included Pseudomonas putida , Streptomyces aureofaciens , Rhodatorula glutinis, Trichoderma harzianum as well as Algae, Oscillatoria geminate on experimental rate were done to combat plant pathogens. The antifungal activities of microorganisms were tested against the five tested foliar pathogenic organism’s i.e. Fusarium oxysporum, Pyrenophora teres, Septoria tritici, Botrytis cinerea and Alternaria solani. The results showed that S. aureofaciens, P. putida and R. glutinis had effective against foliar pathogens. In addition, antifungal metabolites of the cell free bacterial and fungal culture media caused a significant reduction in all pathogen’s growth and germination. Hematological effective of synthetic and biological fungicides showed that the used chemical fungicide for comparison caused effects at recommendation rate. All biocontrol agents has a high degree of safety and the highest biosafety degree which was shown in S. aureofaciens, P. putida and R. glutinis which compared to chemical fungicide. It is recommended that can be using the tested bio-agents as alternative chemical fungicides.