多年生黑麦草根系构型对不同降水量的响应

以多年生黑麦草为试验材料,研究其在模拟小雨(24 h降水量为0.1~9.9 mm)、中雨(24 h降水量为10~25 mm)、大雨(24 h降水量为25~50 mm)3种降水量下根系构型对水分胁迫的响应。结果表明:在胁迫周期内,多年生黑麦草的根总长、根表面积、根体积、根平均直径在CK组(60%小雨降水量)、A组(小雨降水量)、C组(大雨降水量)下均呈先上升后下降的趋势;B组(中雨降水量)下的根长、根表面积、根体积、根平均直径、根分叉数在胁迫全程无下降趋势,各形态指标均显示其生长状态良好。根冠比、比根长、根干质量密度等指标虽然在不同处理组下变化不同,但B组(中雨降水量)水分处理下指标优于其他处理,生长情况稳定良好,从长势看也较适合草坪草的生长。综上所述,多年生黑麦草根系最适宜的生长环境为模拟中雨胁迫,即24 h降水量10~25 mm。

Response of Lolium perenne Root Architecture to Different Rainfall

We studied the response of root system configuration to water stress under three kinds of precipitation in light rain(24-h precipitation of 0.1-9.9 mm), moderate rain(24-h precipitation of 10-25 mm), and heavy rain(24-h precipitation of 25-50 mm) on the experimental materials of Lolium perenne. The total root length, root surface area, root volume and average root diameter of L. perenne in the water treatment group CK, A and C all showed a trend of rising first and then falling;B group of total root length, root surface area, root volume, root average diameter, branch number in stress without falling all the way, the morphological indexes showed that the growth in good condition.Although the indexes such as root-crown ratio, specific root length and root weight density changed differently in different treatment groups, the indexes in group B under water treatment were better than those in other treatments, and the growth condition was stable and good, which was more suitable for the growth of turfgrass. To sum up, the most suitable growth environment for perennial ryegrass roots was simulated medium-rain stress, that is 24-h precipitation of 10-25 mm.