为探究最新发现的植物源生物硝化抑制剂丁香酸对烟草品种K326和云烟85苗期根系生长的影响，通过基质培养试验，设置0、10、25、50、100、200 μmol/L 6个丁香酸浓度，研究了不同浓度丁香酸在不同时间（3 d和5 d）对K326和云烟85主根伸长量和一级侧根发育的影响。结果表明：与对照（0 μmol/L）相比，25~100 μmol/L丁香酸能促进K326主根伸长，在3 d时促进率为13.33%~30.67%，在5 d时促进率降为8.54%~22.55%，最适浓度为50 μmol/L；10~50 μmol/L丁香酸促进云烟85主根伸长，在3 d时促进率为7.81%~18.75%，在5 d时促进率维持在4.10%~10.66%，最佳促进浓度25 μmol/L；丁香酸对两个烟草品种主根伸长的促进效果均为3 d优于5 d。在侧根发育方面，低浓度丁香酸能显著促进K326和云烟85一级侧根数，两个品种促进侧根发育的最适浓度均为25 μmol/L。相关性分析表明，丁香酸处理下两个烟草品种苗期的主根伸长变化率与侧根数变化率呈显著正相关。可见，适宜浓度的丁香酸对两个典型烟草品种苗期主根增长和侧根发育均为促进效应。生物硝化抑制剂丁香酸具有促进烟草根系生长的潜力，为研发烤烟新型专用肥提供了理论依据。

In order to explore the effects of biological nitrification inhibitor syringic acid on the root at seedling stage growth of tobacco varieties K326 and Yunyan 85, a substrate culture experiment was conducted with six concentrations of syringic acid (0, 10, 25, 50, 100 and 200 μmol/L) to investigate the effects of different syringic acid concentrations on the elongation of the primary roots and lateral roots of K326 and Yunyan 85 at different time (3 d and 5 d). The results showed that compared with the control (0 μmol/L), syringic acid in the range of 25-100 μmol/L promoted the primary root elongation of K326 at 3 d and 5 d by 13.33%-30.67% and 8.54%-22.55%, respectively, with the optimum concentration of 50 μmol/L, while syringic acid in a range of 10-50 μmol/L promoted the primary root length of Yunyan 85 at 3 d and 5 d by 7.81%-18.75% and 4.10%-10.66%, respectively, with the optimum concentration of 25 μmol/L. The promotion of syringic acid on the primary root elongation of K326 and Yunyan 85 was better at 3 d than at 5 d. Low concentration of syringic acid significantly increased the numbers of lateral roots of K326 and Yunyan 85, with the optimum concentration of 25 μmol/L for both varieties. Correlation analysis showed that the change rates of main root elongation and lateral root numbers of the two tobacco varieties were significantly positively correlated with syringic acid. It can be seen that the appropriate syringic acid concentration can promote the growth of main roots and lateral roots of two tobacco varieties at seedling stage. Biological nitrification inhibitor syringic acid has the potential to promote the growth of tobacco roots, providing a theoretical basis for the development of new fertilizer for flue-cured tobacco.

S143.1+6

中国烟草总公司贵州省公司重点研发项目（2021XM19）和国家自然科学基金面上项目（32072670）资助。