Background: The faulty development of the root system is a major threat that affects the survival rate of container seedlings of Sapium sebiferum in the transplanting and reforestation processes. The current study was conducted to determine the impact of biochar on the root growth and development of S. sebiferum container seedlings. Methods: Varied concentrations (1%, 3%, and 5%) of straw and bamboo biochar were applied in six groups, whereas the control group (CK) was only treated with matrix. Results: The treatment with 3% straw biochar (C2) proved to be the most effective soil conditioner for cultivating S. sebiferum seedlings. Moreover, C2 increased seedling height (58.92%); ground diameter (33.86%, biomass of the over-ground part (12.73 g), the underground part (7.48 g), and the fibrous part (0.076 g) compared to the CK (control). Conclusions: Biochar not only improved the root morphology by developing primary lateral roots, but it also accelerated the assimilation of N from the matrix to indirectly facilitate stem growth through enhancing NR activity. The change in root growth strategy contributed to the growth in S. sebiferum seedlings, thereby improving the survival rate during transplanting and reforestation.

中文翻译：

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Biochar 改善 Sapium sebiferum (L.) Roxb 的根生长。容器苗

背景：根系发育不良是影响乌桕容器苗移栽和造林过程中成活率的主要威胁。目前的研究旨在确定生物炭对S. sebiferum容器幼苗根系生长和发育的影响。方法：6 组施用不同浓度（1%、3% 和 5%）的秸秆和竹生物炭，而对照组（CK）仅用基质处理。结果： 3% 秸秆生物炭 (C2) 处理被证明是最有效的S. sebiferum土壤改良剂幼苗。此外，C2 增加了苗高（58.92%）；地直径（33.86%，地上部分（12.73 g）、地下部分（7.48 g）和纤维部分（0.076 g）的生物量与 CK（对照）相比。结论：Biochar 不仅改善了根系通过发育初级侧根来促进形态学，但它也加速了基质中 N 的同化，通过增强 NR 活性间接促进茎的生长。根生长策略的改变有助于S. sebiferum幼苗的生长，从而提高了生长过程中的成活率。移栽和重新造林。