A Review on Biological Control of Some Important Plant Diseases Using Fungal Antagonist, Talaromyces Flavus

Abstract

Talaromyces flavus is an important antagonist fungus that plays an important role in the prevention of important pathogenic herbaceous plant diseases. This fungus is located in the rhizosphere of plants, uses root permeations, and produces hydrogen peroxide with the help of glucose oxidase enzymes in the presence of glucose in these compounds. Hydrogen peroxide is a highly toxic compound for fungi and pathogenic bacteria, which can destroy them. The inhibitory mechanisms of this fungus for the growth of pathogenic agents include microparasiticity by chitinase and pectinase enzymes, production of volatile compounds of alcoholic and aldehyde, and the production of non-volatile compounds by the glucose oxidase enzymes, galactosidase and giziosidase. In Iran, the efficiency of various T. flavus isolates has been investigated in the prevention of important pathogens and, consequently, the control of related diseases. The results showed that the T. flavus isolates from different soil and crops, such as cotton, potatoes, sugar, beet, tomatoes and greenhouse cucumbers, each had the most impact on the control of the related diseases. Also, the incidence of the diseases studied (cotton verticillom, potato verticillom, sugar beet seedling death, tomato fusarium wilting and greenhouse cucumber fusarium wilting) decreased by about 30%. Apart from playing an effective role in controlling disease, T. flavus also has a role in the development of vegetative traits like height, dry weight, fresh weight and yield of these products. The plant growth enhancement properties are the result of the production of similar compounds with growth phytohormones of auxin, cytokinin and gibberellin, and fungal intervention in the synthesis of phytohormones by the plant. For application of this fungus in the greenhouse and in the field, its mass production was carried out on various vegetable substrates, including wheat bran, rice bran, pit soil, wheat shrimp, corn wood corn, and pit soil, mixed with rice bran. The relevant research has shown that the most suitable bed was the rice bran bed in terms of efficiency in increasing the active population of fungi for isolates of cotton potato and sugar beet. However, the highest active population of the fungus was observed for tomato and greenhouse cucumber isolates on the pit soil with rice bran. In other studies in order to increase the stability of the fungus on the propagation substrates the stabilizers for volatile and non-volatile compounds, including aminophenol, arboxymethyl cellulose, dicycloserine, sodium nitrate, and magnesium sulfate were used. The results showed that the highest increase in the active population of the fungus occurred after one year of its mass production, with the use of stabilizers of sodium nitrate and dicycloserine.