论文部分内容阅读
采用PVC管栽方法,研究模拟犁底层和深松处理下春玉米花后衰老过程中根系的生物学变化特征。结果表明,在玉米花后,相同根层节根数均表现为深松处理>模拟犁底层处理。犁底层影响根系在不同深度土壤空间分布,深松处理20~35 cm土壤深度和36~75 cm土壤深度玉米根系体积分别比犁底层处理增加176.33%和185.92%;在模拟犁底层处理下,90%以上的根系主要集中在0~20 cm土壤深度,深松处理90%以上的根系主要集中分布在0~35 cm深度土壤。深松增加下层土壤(30~75 cm)根系比重,根系空间分布更加合理。根系衰老进程,花后20 d开始犁底层处理下36~75 cm土壤深度玉米根系衰老速度加快,该深度根系重量开花期比深松处理低2.91%,花后50 d比深松处理低12.31%。犁底层的存在限制玉米根系的发育,深松有利于增加深层土壤的根系分布,能减缓后期根系衰老速度。
The characteristics of the biological changes of root system during the senescence process of spring popcorn under simulated plow bottom and subsoiling conditions were studied by using PVC tube planting method. The results showed that after popcorn, the root number of the same root layer showed subsoiling> simulated plow bottom treatment. The bottom of the plow affected the spatial distribution of soil in different depths. The soil depth of 20 ~ 35 cm and the root volume of corn in 36 ~ 75 cm soil depth increased by 176.33% and 185.92%, respectively, compared with plow bottom treatment; The root system above% mainly concentrated in the depth of 0 ~ 20 cm. The root system covered more than 90% of the deep pine mainly concentrated in the depth of 0 ~ 35 cm. Subsoiling increased the proportion of roots in the lower soil (30-75 cm), and the spatial distribution of roots was more reasonable. Root senescence process accelerated the root senescence of maize roots at 36-75 cm soil depth at 20 d after flowering. The root weight of flowering at the depth was 2.91% lower than that of subsoiling at 50 d, and was 12.31% lower than that of subsoiling at 50 d after flowering . The existence of plow limits the development of maize root system. Subsoiling helps to increase the root distribution of deep soil and slows the rate of root senescence in later period.