Effects of phosphite treatments on cell walls components of potato tubers

OLIVIERI FP; LOBATO MC; LASSO M;; FELDMAN ML;; MACHINANDIARENA MF; ANDREU AB; DALEO G.R

Villa Carlos Paz, Córdoba

Congreso; Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2008

SAIB

Phosphites (Phi) are alkali metal salts of phosphorous acid, with the ability to protect plants against different pathogens. Molecules involved in the protection given by phosphites are still unknown. Preliminary studies of our laboratory showed that the periderm thickness of potato tubers increased in those coming from Phi treated plants. The aim of this work was to analyze modifications in cell wall proteins and pectins in tubers coming from plants treated with potassium phosphite (KPhi). These tubers (cultivars Shepody and Bannock Russet) showed increased resistance to F. solani, P. infestans and E. carotovora. Differences in SDS-PAGE pattern of cell wall proteins were observed between tubers from treated plants respect to control tubers. On the other hand, pectin extracts, obtained by different methodologies, showed that these are modified by KPhi treatment and also after wounding or F. solani infection. The type of pectin and the accumulation were analyzed by immunoblot using JIM5 and JIM7 antibodies. The differences produced in proteins and pectins by KPhi, also showed variations depending on potato cultivar. Morpho-histological analysis will contribute to know if these changes in the cell wall architecture are part of the defense responses induced by KPhi. Supported by UNMDP, CONICET, ANPCyT.