EVALUATION OF THE OXIDATIVE STRESS IN STRAWBERRY PLANT CELL SUSPENSION

MARTOS, GUSTAVO G.; DÍAZ RICCI, JUAN C.

Tafí del Valle. Tucumán

Jornada; 28º Jornadas Científicas de la Asociación de Biología de Tucumán; 2011

Asociación de Biología de Tucumán

Plants under biotic or abiotic stress react producing a series of biochemical reactions that can lead to a defense response and the measurement of reactive oxygen species (ROS), such as H2O2, is very useful to study this plant response. In this work, we present a system to study the intracellular level of H2O2 in plant cell suspensions. Mesophyll cells of 8 weeks old strawberry plants (Fragaria x ananassa) of the cv Pájaro were used. 1.5 g of leaves were washed, cut into squares, and homogenized in a potter with 10 mL of buffer W5. Cells were recovered by differential centrifugation. The level of H2O2 was measured by fluorometry and cellular viability was determined with Blue Evans dye. The suspension (1.5 x 106 cell/mL) was evaluated during 24 hours. Results showed that the initial level of H2O2 decreased approximately 65% after an overnight in the dark at 25°C and cell viability decreased 8% 24 hs after extraction. The system was induced with Paraquat (0.1 mM) showing a peak of H202 production 3 hours after the induction and the effect was completely suppressed when ascorbic acid (5 mM) was added 30 minute previous to Paraquat. These results let us conclude that the developed system of cell suspension constitutes a useful and reliable method to study stress in plants.