中文摘要：

采用砂培试验,以3个油菜品种为试验材料,研究了5种不同供氮水平对根系生长和产量形成的影响。结果表明,随着供氮水平的增加,3个油菜品种的根质量、根体积、根总吸收面积、根活跃吸收面积、侧根数、根长、根系活力及籽粒产量均增加,表现出根系各项指标与籽粒产量之间的正相关关系。其中,根系干质量、根系体积、根系总吸收面积、根系活跃吸收面积对油菜籽粒产量的贡献最大,其次是一级侧根数,根长和根系活力的作用最小。开花期根系指标对产量形成的影响大于苗期根系指标。

英文摘要：

Changes of root morphological,physiological characteristics and yield were studied in five different N application levels with sand culture,using three rape varieties.The results showed that root weight,root volume,root total absorption area,root active absorption area,lateral root number,root length,root vigor and grain yield of the three varieties were increased with the increase of nitrogen（N） application.The relationship between root physiological indexes and grain yield was positive.The contribution of root dry weight,root volume,root total absorption area,root active absorption area to grain yield of oilseed rape was the largest;the number of lateral root was followed and root length and root vigor were the smallest.The root physiological indexes contributed to grain yield bigger at the flowering stage than at the seedling stage.