Preservation of Food Sugar Beet via the Control of <i>Rhizoctonia solani</i> AG 2-2IIIB by Extreme Factors

Abstract

Sugar beet (Beta vulgaris L.) is a valuable sugar-providing crop accounting for around 25% of global white sugar production. It is an integral part of the food industry. Several factors cause a decrease in the yield of this food crop. The infection of phytopathogenic fungi is one of the most hazardous. Though several methods to control Rhizoctonia solani have been developed, the problem is still not solved. Thus, the goal of this work was to investigate the effect of abiotic factors (pH, Eh, presence or absence of O2) and biotic ones (microbial community) on the fungal pathogen R. solani AG 2-2IIIB for its control and sugar beet protection. Microbiological methods were used to conduct the research. Thermodynamic calculations were applied to determine the conditions necessary for suppression of R. solani AG 2-2IIIB. As a result, a comparison of the effect of abiotic and biotic mediated factors on the efficiency of the growth of Rhizoctonia solani AG 2-2IIIB was carried out. Obtained data showed the following: mainly the abiotic factors provided via chemical buffers or removal of oxygen caused the inhibition of R. solani; the values of 5.5 ≤ pH ≤ 8.5, Eh ≤ −200 mV, and oxygen absence inhibited its growth. The maintenance of these factors via microbial communities enhanced the suppressive effect, bringing about the death of mycelium. The study of microbial strains revealed the inhibitory effect of microbial metabolites and provided more effective control of Rhizoctonia solani AG 2-2IIIB.

Keywords

• sugar beet
• pathogenic fungus suppression
• thermodynamic prediction
• extreme factors
• microorganisms