Crecimiento, nodulación y ROS apoplásticas en Lotus japonicus bajo estrés salino

QUERO G., PAROLA R., MELCHIORRE M., LASCANO R., R. RACCA Y V TRIPPI.

Los Cocos, Córdoba 25-29 de Marzo 2007

Congreso; XXIII Reunión de la Asociación Latinoamericana de Rizobiología RELAR-2007 y I Workshop sobre Biofertilización en Iberoamérica.; 2007

Asociación Latinoamericana de Rizobiología

Legumes from Lotus genus have a major value as forages in salty soils. Lotus japonicus (MG20) a model legume is frequently used to study mechanisms related with stress tolerance. We propose that antioxidant defense activation and modulation of reactive oxygen species (ROS) production, enable plants to cope with stress and support growing. Salt treatment was made by acclimation at 50 or 150 mM NaCl. Shoot and root growing was promoted by 50 mM NaCl treatments behavior that correlated with antioxidant enzymes induction. Furthermore nodule production was not affected and root growing correlated with increases in apoplastic superoxide anion (.O2) generation in the root tips. Under 150 mM NaCl, shoot and root growing, nodulation and appoplastic ROS production decreased  markedly whereas increases in SOD and GR activities were maintained. Relative water content (RWC) did not show significant differences respect to the control. This results suggests that growing and nodulation are mainly affected by ionic component of salinity, and also that these processes could be related with appoplastic ROS generation.