Is the cell wall reinforcement a potential tool for the early screening of resistance in breeding program

KORGAN S.; WOLSKI E.A.; CICORE P.L.; SUAREZ P.A; CAPEZIO S; HUARTE M; ANDREU A.B

Villa Carlos Paz. Cordoba, Argentina

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

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular.

Horizontal resistance is a valuable tool for potato Late blight control, caused by the oomycete Phytophthora infestans. In Argentina several sources of horizontal resistance were identified. In particular, the wild specie Solanum tarijense (trj) has shown high levels of resistance. Previous results with trj clones moderately resistance to Late Blight, showed high levels of PR activities, such as, ß-1,3-glucanases, chitinases, peroxidases (POX) and polyphenol oxidases (PPO). The use of these chemical markers as a potential tool to screen for horizontal resistance was studied. The defense response in trj clones through the induction of lignin, callose, phenolic compounds, as the activities involved in the cell wall strengthening, POX and PPO, was analyzed. Leaf tissue from resistant clones responded to P. infestans infection though the deposition of lignin, callose and phenolic compounds. All these changes were preceded by the activation of the enzymes involved in the synthesis and polymerization of these compounds. However, for the susceptible clones slight increases were detected. These results suggest that the analysis of the compounds related with the cell wall strengthening could be a potential tool for early screening of horizontal resistance in breeding program. Supported by SECyT, INTA and Banco Santander Rio.