关键词: 土壤容重, 玉米, 根系

Abstract: A study on corn root growth and activities at different soil layers with special bulk density was conducted using pot cultivation in a field experiment. The results showed that corn root growth and activities were greatly affected by soil BD（bulk density）in deep soil layers. Corn root number, root dry matter, root length and root activities decreased with the increase of soil BD in deep soil layers. The larger the soil BD, the more significant the decrease. The amount of total corn root decreased with the increase of average soil BD. More air roots were observed in a smaller average soil BD. For Yuyu23, its root couldn't penetrate a length of 20 cm in soil layers with a soil BD of 1.6 g·cm-3. It was found that root growth had certain compensative effect in soil layers with smaller soil BD, but such an effect was too limited to make up for the adverse effect caused by larger soil BD.

Key words: Soil bulk density, Corn, Root system