Występowanie i rola ekologiczna grzyba Puccinia komarovii w Polsce – konsekwencje dla ochrony przyrody

Puccinia komarovii Tranzschel (1936) is a pathogenic fungus of the family Pucciniaceae, whose natural hosts are plants
of the genus Impatiens. In Poland, its only host is the invasive small-flowered balsam, Impatiens parviflora. This study provides
a synthesis of current knowledge on the distribution of this fungus species in Poland, its population dynamics, and its ecological
significance in the context of nature conservation. The analysis was based on data collected from the 1990s to 2025, the results
of the latest molecular studies, and data from the relevant literature.
The first record of P. komarovii in Poland dates back to 1934 (Silesia region). Recent studies have confirmed the widespread
presence of the pathogen in numerous national parks: Wigry (over 250 sites), Drawa, Wielkopolska, Wolin, Świętokrzyski, Gorce,
Słowiński, Roztocze, Pieniny, and Góry Stołowe (Table 1), as well as in other areas, particularly in southern Poland (Table 2, Fig. 1).
Detailed observations conducted in Drawa National Park (DPN) and Wigry National Park (WPN) revealed significant variation
in infection intensity. In selected locations, the proportion of infected plants ranged from 25% to 100%. Molecular analyses
of isolates confirmed that the Polish populations belong to the subspecies P. komarovii var. komarovii and revealed genetic diversity
in comparison with isolates from the Wielkopolska region.
The pathogen exhibits high host specificity; no infections of the native common balsam Impatiens noli-tangere were recorded during
the three-year study. Infection causes significant host weakening, including reduced biomass and reproduction, and, under conditions
of high pathogen pressure, seedling mortality reaching 100%. These results confirm the potential of P. komarovii
as a natural factor limiting the expansion of I. parviflora in Polish forest ecosystems. Further research should focus on monitoring
the population dynamics and genetic variability of this fungus.