After drought stress, the root to shoot ratio(R/S) of Brazilian upland rice varieties increased significantly, the rising extent was 28.8%, but the root to shoot ratio(R/S) of normalrice varieties changed few.

• 旱稻品种巴西陆稻根冠比(R/S)在干旱胁迫后显著上升，上升幅度达28.；8%25，而不同常规稻品种根冠比(R/S)在干旱胁迫后的变化均不明显。