松嫩平原不同株型玉米品种根系分布特征比较研究

Comparison of roots distribution in different maize plant type cultivars in the Songnen Plain

采用土柱模拟栽培法与大田试验相结合的方法 ,对松嫩平原不同株型玉米的根系分布特征进行了比较 .结果表明 ,平展型玉米和紧凑型玉米根干重最大值出现的时期不同 ,二者根干重分别在抽丝后 15d和抽丝后 30d时达到最大值 .成熟时紧凑型玉米根干重比平展型高 12 .2 % .二者根系垂直分布有明显的差异 ,在 2 0cm以下的根干重比率 ,平展型玉米在 19%以下 ,而紧凑型玉米高于 2 3% .紧凑型玉米的深层根量较多 ,在深 4 0～ 10 0cm土层内根干重比率比平展型高 4 2 .3% .二者的根系水平分布也不同 ,紧凑型玉米根系水平分布较集中 ,在距植株 0～ 10cm水平范围内 ,根系分布比率比平展型玉米高 9.6 % .紧凑型玉米深层根量较多 ,水平分布集中 ,耐密植 ,是易获得高产的重要原因之一 .

By soil column culture and field experiment, the comparison of roots distribution of spreading-leaf and upright-leaf maize cultivars in the Songnen Plain was studied. The results showed that there were differences in the roots distribution of different maize cultivars. The maximum of root dry weight appeared on the 15th day and 30th day after silking for spreading-leaf and upright-leaf maize cultivar, respectively. Compared to spreading-leaf maize cultivar, the root dry weight of upright-leaf maize cultivar was higher by 12.2%. The vertical distribution of different maize cultivar roots was different. The root dry weight rate below 20 cm depth of spreading-leaf maize cultivar was less than 19%, whereas that of upright-leaf maize cultivar was more than 23%. Compared with spreading-leaf maize cultivar, the root dry weight rate at 40～100 cm depth was higher by 43.3%. There were differences between the different maize cultivars in the horizontal roots distribution. The roots of upright-leaf maize cultivar distributed tightly in horizon. The percentage of root dry weight of upright-leaf maize cultivar in a horizontal area 0～10 cm from the plant center was higher than that of spreading-leaf maize cultivar by 9.6%. Upright-leaf maize cultivar had more roots in deeper soil depth and it distributed tightly in horizon. Therefore, it was suitable for compact-planting. It was easier to acquire high yield for upright-leaf maize cultivar because it had good roots distribution characteristics.