Abstract: The variation of root growth ability in seedling stage among rice varieties and its heterosis and genetics were studied wit 8 rice varieties and 4 × 4 incomplete dialle crosses. There were significant difference of nmbers of root, root length, root width and root growth ability among varieties. The heterosis was great and variation among crosses was great. They were mainly controlled by non-additive heredity.

Key words: heredity, root growth ability, seedling stage

摘要： 用8个品种进行4×4不完全双列杂交进行试验。结果表明，在品种间存在明显的根数、根长、根宽和发根力差异。杂种优势较大，且组合间变异非常大。其主要受菲加性遗传控制。

关键词: 苗期, 发根力