在霍格兰营养液中分别设置6个不同浓度(0、0.1、0.2、0.4、0.8、1.6 mg·L−1)处理的植物生长调节剂吲哚丁酸(IBA),研究其对烟苗生物量的影响。结果表明,随着吲哚丁酸浓度的变化,烟草幼苗根干重、地上部干重、壮苗指数的变化一致呈现先上升后下降的趋势。在处理烟苗时,使用0.8 mg/L和1.6 mg/L的高浓度吲哚丁酸均导致了烟苗生物量的减少,其他浓度的吲哚丁酸处理相较于对照组,均促进了烟苗生物量的增长。当吲哚丁酸的浓度为0.4 mg/L时,其对烟苗生物量的提升效果最为显著。0.4 mg/L吲哚丁酸处理较其他处理提升了生物量,根系干重、地上部干重、壮苗指数,增长幅度分别达到6.94%~97.44%、5.27%~73.91%、6.25%~109.96%。综合试验条件下0.4 mg/L的吲哚丁酸浓度为烟草漂浮育苗营养液的最佳浓度。The plant growth regulator indolebutyric acid (IBA) was treated with 6 different concentrations (0, 0.1, 0.2, 0.4, 0.8, 1.6 mg·L−1) in Hoagland nutrient solution to study the effects of IBA on the biomass of tobacco seedlings. The results showed that with the increase of indolebutyric acid concentration, the changes of root dry weight, above-ground dry weight and strong seedling index of tobacco seedlings were consistent, and increased first and then decreased with the change of concentration. Both 0.8 mg/L and 1.6 mg/L high concentration indolebutyric acid treatments reduced the biomass of tobacco seedlings, and other indolebutyric acid treatments increased the biomass of tobacco seedlings compared with the control, among which 0.4 mg /L indolebutyric acid treatment had the most significant increase effect. Compared with other treatments, 0.4 mg/L indobutyric acid treatment increased the biomass, root dry weight, above-ground dry weight and seedling strength index by 6.94%~97.44%, 5.27%~73.91% and 6.25%~109.96%, respectively. Under the comprehensive test conditions, indolebutyric acid concentration of 0.4 mg/L was the best concentra
