Figure 1

Influence of duration of waterlogging and nitrogen application on the content of chlorophyll of rapeseed leaves under pot and field experiments. Values are means of three replicates ±SE. Small alphabetical letters above mean denote the significant differences among treatment at P ≤ 0.05. N1, 0 kg ha−1; N2, 30 kg ha−1; N3, 60 kg ha−1; and N4,90 kg ha−1. D0, refers to without waterlogging; D6, refers to waterlogging for 6 days and D9, refers to waterlogging for 9 days.