NEW RACES OF PUCCINIA HELIANTHI SCHWEIN – IS THE CAUSATIVE AGENT OF SUNFLOWER RUST IN THE RUSSIAN FEDERATION
Over the past two decades, over different years, depending on weather conditions, a strong distribution of rust on sunflower has been systematically observed in the Tambov, Lipetsk, Saratov, Volgograd regions, Krasnodar Territory and other places of the Russian Federation. This disease caused by the highly specialized fungus Puccinia helianthi Schwein was noticed in Russia in 1866. Since then, systematically recurring epiphytoties have been described by many domestic authors as well as by scientists from other countries where sunflower is cultivated and affected by this pathogen. Sunflower breeding for resistance to rust was not carried out in the Russian Federation since 1983. The objectives of our research was to determine the race of some isolates of the sunflower rust pathogen collected in the Krasnodar Territory, Saratov and Lipetsk regions using an internationally accepted set of sunflower resistance differentiating lines. Eight standard lines were used: CM 90, CM 29, P-386, HA-R1, HA-R2. HA-R3, HA-R4, HA-R5. As a differentiator, susceptible to all races of the pathogen, we used the sunflower variety VNIIMK 8883. Six physiological races of P. helianthi were revealed. Four of them: 700, 710, 722, 772 were discovered in the Russia for the first time. In addition to these new pathotypes, the old races 100 and 300 have been identified. It is possible that there are other pathogen races that have not yet been found on the territory of the Russian Federation. Therefore, it is necessary to examine a larger number of fields in different regions and increase the number of isolate samples for identification.