ROMERO Fernando Matias
congresos y reuniones científicas
SALICYLIC ACID MEDIATES CHANGES IN POLYAMINE METABOLISM OF TOBACCO PLANTS INFECTED BY S.sclerotiorum
ROMERO FM; MARINA M; ROSSI FR; GÁRRIZ A; RUIZ OA; PIECKENSTAIN FL
San Miguel de Tucumán, Tucumán República Argentina
Congreso; XLV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2009
Sociedad Argentina de Investigación en Bioquímica y Biología Molecular
Polyamines (PAs) are natural aliphatic polycations with multiple functions. PA metabolism undergoes significant changes during plant responses to various stresses. Previously, our group found that PA levels vary both local and systemically in tobacco plants infected by S. sclerotiorum. The aim of this work was to gain insight into the role of salicylic acid (SA) in the modulation of PA metabolism during local and systemic responses of tobacco to fungal infection. Changes in PA metabolism of wild type (WT) plants induced by S. sclerotiorum infection were compared with those of transgenic (NahG) plants unable to accumulate SA. Locally, the levels of some apoplastic PAs increased after lesion development both in WT and NahG plants. When systemic levels of PAs were analyzed, putrescine levels of WT plants were found to be higher in infected plants than in controls, but in NahG plants the levels of this diamine and other PAs were lower in infected plants than in controls. The activity of enzymes involved in PA catabolism was not affected by infection of WT plants, neither local nor systemically, whereas in the NahG line the activity of these enzymes was different between control and inoculated plants. These results show that SA and PA metabolism are interconnected during local and systemic responses of tobacco plants to infection by the necrotrophic fungus S. sclerotiorum.