Dependence of Phytotoxicity of Cultural Filtrates of the Flax Anthracnose Pathogen Colletotrichum Lini Manns Et Bolley Strains on the Amino Acid Composition

Abstract

The aim of this work is to determine the amino acid composition of the cultural filtrates of the flax anthracnose fungus Colletotrichum lini Manns et Bolley strains to adjust the concentration of the selective agent in the nutrient medium when creating new flax genotypes resistant to anthracnose in vitro. It was found that the cultural filtrates of strains 527 and 608 contain such amino acids as alanine, glycine, asparagine, cysteine, threonine, aspartic acid, glutamic acid, as well as arginine in the highly virulent strain 527. The traces of tyrosine and lysine in the weakly virulent strain 608 were also found. On the day of cultivation, the supply of nutrients in the cultivation medium was apparently depleted, and the fungus began to use the products of its vital activity for life support. In the culture filtrate of the highly virulent strain 527, the concentration of all certain amino acids was significantly higher than in the culture filtrate of the weakly virulent strain 608. It was shown that the 23-day culture filtrate of the highly virulent strain 527 had the highest toxicity which is lower than in all genotypes taken in the study. The toxicity of the culture filtrate depends on the virulence of the anthracnose pathogen strain. The culture filtrate of a highly virulent strain is more toxic than a weakly virulent one. The presence of cysteine in the culture filtrates of the strains increases the possibility of inhibiting the growth and development of flax cells in in vitro culture. When using the culture filtrate of anthracnose pathogen strains containing asparagine, glutamine, serine, glycine, aspartic and glutamic acids, it is possible to induce the growth and development of flax cells in vitro. As the fungal mycelium grew in the culture filtrates, the concentrations of alanine, asparagine, glycine, aspartic and glutamic acids decreased. Due to the high concentration of cysteine and tyrosine, the culture filtrates of strains 419 and 639 were toxic during the entire study period (up to 42 days).