U radu je ispitivan biotički stres u klijancima soje izazvan gljivom Macrophomina phaseolina (Tassi Goid.), patogenom biljaka i uzročnikom ugljenaste truleži korena i donjeg dela stabla. Različite karakteristike izolata gljive (dobijenih sa šećerne repe (2), kukuruza (1), soje (1) i suncokreta (1)), ispitane su u dve sorte soje (Meli i Balkan). Poređenje antioksidantnih sistema u biljkama soje ukazalo je na različite odgovore između sorti soje inficiranih izolatima M. phaseolina različitog porekla. Izolati su izazvali intenzivnu reakciju u inficiranim klijancima: najveća patogenost zabeležena je kod izolata sa šećerne repe ŠR62/4 (2.80). Izolati ŠR55(3)/09 (2.58), MphSo (2.32) i MphSu (2.26) nisu pokazali statistički značajnu razliku u patogenosti. Izolat sa kukuruza, MphK, pokazao je najnižu patogenost (1.94). Za većinu ispitivanih biohemijskih parametara (lipidna peroksidacija, aktivnost fenilalanin amonijum-liaze, sadržaji ukupnih polifenola, tanina i proantocijanidina), izolat ŠR55(3)/09 sa šećerne repe, izazvao je najintenzivnije i najznačajnije reakcije u klijancima soje u poređenju sa svim ostalim ispitanim izolatima. Njegovo prisustvo u poljskim uslovima se mora podvrgnuti monitoringu, a o rotaciji useva na takvim oranicama se mora povesti više pažnje.

The research was focused on biotic stress caused by Macrophomina phaseolina (Tassi) Goid., a plant pathogen that causes charcoal rot by infecting the root and lower stem of soybean. Differences in pathogenicity of fungi cultures from five isolates (two from sugar beet, one from maize, one from soybean and one from sunflower) have been investigated in seedlings of two soybean cultivars (Meli and Balkan). Comparison of antioxidant systems of soybean seedlings showed different reactions of plants infected with M. phaseolina isolates of different origin. The highest pathogenicity showed isolate from sugar beet ŠR62/4 (2.80), while no significant difference was found for isolates ŠR55(3)/09 (2.58), MphSo (2.32) and MphSu (2.26). The isolate from maize, MphK, showed lowest pathogenicity (1.94). For the most of the biochemical parameters tested (lipid peroxidation, phenylalanine ammonium-lyase activity, total polyphenols, tannins and proanthocyanidins contents) the isolate from sugar beet (ŠR55(3)/09) induced the most significant reaction in soybean seedlings among all isolates investigated. Presence of this pathogen in the field conditions should be further monitored and the crop rotation should be seriously taken into account.