Non-thermal effects of 2 MHz ultrasound on the growth and cytology of Vicia faba roots.

Abstract

Abstract The effect of 2 MHz ultrasound at intensity levels from 1 to 20 W/cm2 on growth rate, lateral root formation, mitotic index and chromosome morphology was studied. The ultrasound produced an immediate reduction in growth rate on the first post-exposure day followed by recovery to control value after ten days. Ultrasound reduced lateral root formation and mitotic index. Intensity and time dependent relations were found for growth rate reduction and lateral root formation. No “classical” chromosome aberrations were found but chromosomal anomalies—bridged prophases and metaphases and agglomerated metaphases—of another nature were observed after sonication: these anomalies were quantitated into a damage index.