Effects of duration and intensity of aluminum stress on growth parameters in four rice genotypes differing in aluminum sensitivity

Abstract

The effects of aluminum (Al) stresses of varying intensities and durations on growth parameters were investigated in four Oryza sativa L. genotypes (two Al sensitive, two Al resistant). Our results support the current opinion that the use of only one parameter cannot easily account for differences in Al resistance, since Al concentration or stress duration can affect plant responses in opposite directions. For short stress duration (40 days) at Al 500 μM, weight parameters appear to be more discerning than length parameters. Necrosis evaluation is a more reliable criterion for plants maintained for a long time (80 days) in the presence of high Al concentrations (Al 1000 or 1500 μM).