An??lisis de expresi?3n de tres genes relacionados a estr??s en respuesta a un exceso de boro en Solanum lycopersicum cv Poncho Negro

摘要

Boron (B) is an essential micronutrient for higher plants, but is very toxic at higher concentrations. This study evaluated the tran-scriptional activity of three stress-related genes under conditions of excess B in Solanum lycopersicum cv Poncho Negro, a cultivar originating from the Lluta Valley (Arica, Chile), where it grows in environments with very high concentrations of B. Poncho Negro tomato seedlings were grown under hydroponic conditions and stressed with B (20 ppm); root and leaf samples were collected at 3 and 96 h after stress. The activity of three stress-related genes, Hsp90, MT and GR, was analyzed by quantitative reverse transcrip-tion PCR. A marked differential molecular response was observed between leaves and roots. The three genes were overexpressed in leaves in response to B, while in roots Hsp90 decreased, MT increased and GR1 did not change its activity. Activation of these genes may indicate participation of genes involved in stress oxidative processes as an early response to B stress and may represent a complementary mechanism to boron transport.