Abstract
Maize inbred lines, mainly collected from Japan and the United States of America were evaluated for their pre-germination flooding tolerance and waterlogging tolerance at the seedling stage. Pre-germination flooding tolerance, evaluated by germination rate of the seeds soaked for 8 days at 25°C, showed wide variations among 46 lines. Waterlogging tolerance at the seedling stage was evaluated by the dry weight ratio (treatment/control) after exposure to flooding for 2 weeks. The waterlogging tolerance showed an extremely wide variation among 223 inbred lines, and some highly tolerant lines were selected. Correlation coefficients between replications were 0.415 in pre-germination flooding tolerance and 0.464 in waterlogging tolerance, indicating the significant repeatability of the experiments. Pre-germination flooding tolerance of maize was independent of the waterlogging tolerance at the seedling stage.