Plant Protection News (Vestnik Zashchity Rasteniy)

Fungi associated with potato and their significance as pathogens in Russia

2024-12-24T11:23:05+00:00

Despite the great attention paid to the study of potato diseases, inaccuracies in the names of diseases, their practical significance, and incorrect use of the scientific names of causal agents can be commonly found in the scientific literature. This may lead to confusion and reduces the value of published information in phytosanitary efforts. This review continues the series started with the publications devoted to wheat and barley diseases. This article includes information about the main potato diseases and pathogenic organisms causing them, as well as the species emerging as a potential threat to potato. The current taxonomic status of fungal species and fungus-like organisms associated with various organs of potato is given, and the breadth of their distribution and degree of impact on the crop are summarized. The micromycetes were divided into two groups according to their phytosanitary importance. The first group is represented by fungi of great importance as pathogens causing the 13 economically important potato diseases. The second group consists of fungi causing 25 minor and poorly studied diseases with unconfirmed harmfulness, or potential endophytic fungi. Perceptions of their ability to cause disease remain controversial and the available data require confirmation. This dataset can be used as a reference for a more accurate description of the phytosanitary situation. The review will also be helpful for more targeted studies using molecular techniques to clarify taxonomy and geographic ranges of fungi associated with potato and to provide more detailed data on disease levels in this crop.

Pectolytic bacteria of the genus Pseudomonas from diseased potato tubers

2024-12-24T10:31:50+00:00

Bacteria of the genus Pseudomonas were isolated in axenic cultures from tubers with signs of soft rot in storage facilities of Kamchatka Krai and Kostroma Oblast. The isolated strains differed from each other and from the strains of pectolytic Pseudomonas isolated from potatoes by other authors in the sequences of the genes of 16S ribosomal RNA, DNA gyrase subunit B, and the sigma factor of DNA-dependent RNA polymerase. The strains caused pectolytic softening of potato tissue at temperatures of +10 °C and +25 °C, the affected area of potato tissue fluoresced when illuminated with ultraviolet light. At a temperature of +37 °C, the growth of the strains was inhibited.

Pathogenicity of Fusarium fungi to cereal crops

2024-12-24T10:31:49+00:00

The pathogenicity of Fusarium sambucinum species complex (SC), F. tricinctum SC, F. incarnatum-equiseti SC, F. oxysporum SC, and F. solani SC, which are common root rot pathogens in Belarus, was investigated. As many as 288 isolates were obtained from winter cereals (wheat, triticale, rye, and barley) and spring cereals (barley, wheat, triticale, and oats) and tested on seedlings under laboratory conditions. The most pathogenic fungi were F. sambucinum SC and F. tricinctum SC, while F. incarnatum-equiseti SC, F. oxysporum SC and F. solani SC were weak pathogens. The pathogenicity of Fusarium fungi varied between crops. For example, F. sambucinum SC was the most pathogenic on winter wheat, triticale, and rye and spring triticale and oats, whereas F. tricinctum SC was an aggressive pathogen on winter and spring barley. Fusarium sambucinum SC and F. tricinctum SC were both aggressive pathogens on spring wheat.