Diversity of sunflower rust pathogen biotypes in the regions of the Russian Federation

Abstract

The spread and development of sunflower rust in the regions of the Russian Federation is due to the emergence of new biotypes of the pathogen, which have overcome the resistance of cultivated varieties and hybrids. The aim of the research was to identify isolates of the sunflower rust pathogen collected in 2020-2022 in 8 regions of crop cultivation according to the internationally accepted classification: Krasnodar, Volgograd, Saratov, Voronezh, Ulyanovsk, Penza, Orenburg, and Tambov regions of the Russian Federation. Differential lines of sunflower rust resistance (CM 90, CM 29, R-386, HAR-1, HAR-2, HAR-3, HAR-4, HAR-5) and the variety VNIIMK 8833 susceptible to all races of the pathogen were used for testing. A total of 280 isolates of urediniospores of the parasite collected from infected plants of different sunflower genotypes were identified according to the internationally accepted classification. In this sample, 27 biotypes of rust pathogens were differentiated. There have been identified fifteen biotypes not previously found in Russia, their code numbers are 320, 701, 703, 710, 720, 721, 730, 742, 744, 747, 761, 765, 766, 771 and 777. The most virulent biotype 777 was detected in 2022 among isolates from the Volgograd region. The biotype with the code number 700 was detected in all the regions presented, accounting for 50 % of the sample of isolates studied. It is advisable to carry out sunflower breeding for its resistance.

Keywords

• puccinia helianthi
• spreading
• infestation
• sunflower
• differential lines
• urediniospores
• identification