3种植物根系受折愈伤后抗折力学特性研究

发布时间：2018-09-03 12:21

【摘要】：本文以小叶锦鸡儿(Caragana microphylla)、沙柳(Salix psammophila)、中国沙棘(Hippophae rhamnoides)直根和侧根分支处为研究对象,于5月对正常生长不离体的直根和侧根分支处分别施加3种程度的损伤折力(为该径级平均极限折力的30%、50%和70%),并将受力后的根系埋回,待根系愈伤3个月(5～8月份)和5个月(5～10月份)后挖出,研究根系受损愈伤后成活率、活性值和根径的变化,以及极限抗折力和抗折强度。研究结果如下:(1)1～4mm根径范围内的3种植物直根和侧根分支处,分别承受3种损伤力,分别经过3个月和5个月愈伤后的平均存活率均大于60%;愈伤后的根系活性值小于平行对照;3种植物愈伤后的根系直径均较施加损伤力时有所增加。(2)对于直根和侧根分支处,承受3种程度的损伤力愈伤后,其极限抗折力与直径均呈幂函数正相关,抗折强度与直径均呈幂函数负相关关系。根系愈伤后的极限抗折力、抗折强度与对照相比,均呈减小趋势,损伤力越大,减小幅度越大。(3)对于承受相同程度损伤力的直根和侧根分支处,愈伤3个月后小叶锦鸡儿、中国沙棘根系的抗折力、抗折强度均表现为直根大于侧根分支处,小叶锦鸡儿侧根分支处分别承受30%,50%,70%的极限折力愈伤3个月后,其抗折强度分别为相同条件下直根的67%,65%和65%;中国沙棘侧根分支处愈伤后的抗折强度分别为直根的59%、57%和53%。沙柳愈伤后直根与侧根分支处抗折力、抗折强度随差异不明显。(4)3种植物相同径级的直根承受相同程度损伤力,愈伤3个月后的极限抗折力、抗折强度均小于愈伤5个月。(5)3种植物同部位、同径级根系承受3种程度折力愈伤后的抗折力和抗折强度种间差异与正常生长根系的规律一致,均为小叶锦鸡儿沙柳中国沙棘。
[Abstract]:The direct root and lateral root branches of (Caragana microphylla), Salix (Salix psammophila), of Hippophae rhamnoides chinensis were studied in this paper. In May, three degrees of damage force (30% and 70% of the average ultimate flexural force) were applied to the straight root and lateral root branch of the normal growth, respectively, and the root system was buried back after the stress. The survival rate, activity value, root diameter, ultimate flexural resistance and flexural strength of root callus were studied after root callus were harvested for 3 months (May / August) and 5 months (May / October). The results are as follows: (1) the direct roots and lateral root branches of three species of plants in the 1~4mm root diameter range are subjected to three kinds of damage forces, respectively. After 3 and 5 months, the average survival rate of callus was higher than 60 and the root activity value of callus was smaller than that of parallel control. (2) the root diameter after callus was higher than that at the same time. (2) for the branches of straight root and lateral root, the diameter of roots after callus was higher than that after callus injury. The ultimate flexural strength was positively correlated with the diameter and the strength was negatively correlated with the diameter. Compared with the control, the ultimate flexural strength of root callus decreased, and the greater the damage force, the greater the extent of reduction. (3) for the straight root and lateral root branch which suffered the same degree of damage, 3 months after callus, Caragana microphylla, The flexural strength of the roots of Hippophae rhamnoides was greater than that of the lateral roots, and the lateral root branches of Caragana microphylla were subjected to 30% or 70% of the ultimate flexural strength after 3 months of healing. The flexural strength of the lateral root branch of Hippophae rhamnoides was 59.57% and 53.53% of that of the straight root, respectively, and that of the lateral root branch of Hippophae rhamnoides chinensis was 59.57% and 53.53% of that of the straight root, respectively. There was no significant difference in the flexural strength between the straight root and the lateral root branch after callus injury. (4) the direct roots of the three species of plants with the same diameter class suffered the same degree of damage, and the ultimate flexural strength after 3 months of callus injury. (5) in the same part of the three plants, the difference of resistance and strength between species and normal growth root system was consistent with that of normal growth root system, all of them were Hippophae rhamnoides chinensis.
【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：Q948

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