田间条件下水稻根系分布及其与土壤容重的关系

 采用大田和筒栽方法研究了超高产三系杂交稻协优9308和两系杂交稻两优培九在穗分化期和开花期根系生长和分布及土壤容重对根系分布的影响。结果表明，在田间条件下，土层15 cm内水稻根系占根系总量的89%～98%，深层根系丛间比丛中比例高。不早衰的协优9308根系生长量较两优培九大。土壤容重提高，根系总生长量下降，且深层根系的量和比例下降。就深耕法对水稻根系生长和分布的影响进行了讨论。

Roots Distribution of Rice in Field and its Relation to Soil Bulk Density

Experiments were carried out with super high yielding three line hybrid rice Xieyou 9308 and two line hybrid rice Liangyoupeijiu in the field and pot experiment. Results showed that 89%-98% of roots distributed within 15 cm of soil layer at panicle initiation and flowering stage in the field conditions and percentage of deep roots between hills was higher than that in the center of hills. Roots biomass and percentage of deep roots of Xieyou 9308 with lower senescence of leaf was higher than those of Liangyoupeijiu. Under the higher soil compaction, root biomass decreased, and the amount and percentage of deep roots decreased also. Effects of deep tillage on root growth and distribution of rice were discussed.