INVESTIGADORES
ROMERO Fernando Matias
congresos y reuniones científicas
Título:
Toxic effect of phytotoxin Sirodesmin PL on Brassica napus (colza) seedlings
Autor/es:
ROSSI FR; ELLIOTT C; ROMERO FM; GÁRRIZ A; RUIZ OA
Reunión:
Congreso; XXXII Reunión Argentina de Fisiología Vegetal (RAFV) y XVI Congreso Latinoamericano de Fisiología Vegetal; 2018
Resumen:
Leptosphaeria maculans is a hemibiotrophic fungusthat affect a wide number of horticultural and agronomiccrops such as colza (Brassica napus ssp oleifera).This fungus causes necrosis in leaves and cankers inthe stem base and originates important economic losses.The pathogen´s virulence depends largely on the productionof secondary metabolites, including the phytotoxinSirodesmin PL. This toxin belongs to a wide group of compoundsnamed epipolythiodioxopiperazine which are characterizedby the presence of an internal disulphidebridge. It has been demonstrated that L. maculans mutantsnon-producing sirodesmin are less virulent onstems of B. napus. Nevertheless, the toxicity mechanismsof this toxin is far from being understood. Here we demonstratethat Sirodesmin induces necrotic lesions incotyledons at concentrations ranging 5-50 μM, which isin concordance with cell death levels. The ability of Sirodesminto cause cell death was abolished when this compoundwas maintained in the reduced state by thesimultaneous presence of NaBH4. Sirodesmin inducesROS accumulation as evidenced by DCFDA staining, aswell as H2O2 and superoxide accumulation by DAB andNBT staining, respectively. Here we demonstrate that thistoxin require functional thiols for its toxicity and that itmodifies the redox status in plants.