Improvements in the Root Morphology, Physiology, and Anatomy of Platycladus orientalis Seedlings from Air-root Pruning

作者：Zhipei Feng, Xitian Yang, Hongyan Liang, Yuhua Kong, Dafeng Hui, Jiabao Zhao, Erhui Guo, Beibei Fan · 发表于：HortScience · 年份：2018 · DOI：10.21273/hortsci13375-18 · 被引用次数：12 · 研究领域：Plant nutrient uptake and metabolism、Growth and nutrition in plants、Seedling growth and survival studies

Air-root pruning (AP) has been identified as an effective technique for enhancing root growth and development. However, little information is available regarding the temporal changes in the root system of Platycladus orientalis (L.) Franco under AP. We performed integrated morphological, physiological, and anatomical analyses of the roots in P. orientalis seedlings that had been air-root pruned for 120, 150, and 190 days. Our results found that the whole root length, number of root tips, and root surface area of AP seedlings at 120, 150, and 190 days were higher than those of the non–root-pruned (NP) seedlings ( P < 0.05), but the average root diameter did not differ significantly between the treatments. Compared with NP treatment, AP increased the root length, surface area, number of tips, and specific root length of the ≤0.5 mm diameter roots in P. orientalis during the experimental periods ( P < 0.05), but those of 0.5- to 1-mm-diameter roots were only increased on day 190 ( P < 0.05). The AP plants also exhibited higher root vitality and proportion of live fine roots than the NP plants ( P < 0.05). Our anatomical evaluation of the ≤0.5 mm roots and taproots revealed features that could account for the morphological differences found between the AP and NP plants. In conclusion, our results indicate that air-root pruning induced changes in the roots that promote the root system development in P. orientalis compared with the NP treatment during the experimental p...