Defense mechanisms induced in BABA in multigenic resistance potato cultivars. Systemic response against Phytophthora and Fusarium.

OLIVIERI, F. P.; GONZALEZ ALTAMIRANDA, E.; LOBATO, C.; DALEO, G. R.; ADRIANA BALBINA ANDREU

Pinamar. Argentina

Congreso; SAIB 41th Annual Meeting; 2005

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

The aim of this work was to characterize the biochemical mechanisms by which BABA (β-amino-butyric acid) increases resistance in potato against phytopathogens by promoting a systemic acquired resistance. Two potato cultivars, with different level of horizontal resistance to P. infestans, were analyzed. BABA applications were carried out at different times during plant growth and defense response were analyzed in post harvest tubers. BABA application did not affect tuber harvest yield. Moreover, in our greenhouse conditions, the number and weight of tuber recovered from BABA treated plants increased respect to control plants. The levels of phytoalexins increased in Phytophthora infected tubers, and this increase was higher in tubers from BABA treated plants. In addition, the expression of an aspartic protease also increased in tubers from treated plants, in both cultivars. In potato-Fusarium interaction the accumulation of a fungal serine protease was lower in infected tubers from treated plants respect to infected but non treated tubers. This decrease correlates with a higher plant aspartic protease expression in the same system. It is also necessary to evaluate the durability of this defense response in tuber during storage and to know the optimal time of BABA application to obtain a effective SAR