两种植物生长调节剂及用量对烟草幼苗根系发育的影响

Effects of Two Plant Growth Regulators and Dosages on Root Development of Tobacco Seedlings

为了研究植物生长调节剂在烟草育苗过程中的作用,探究其对烟草幼苗根系生长发育的影响。在烟草漂浮育苗营养液中分别添加两种植物生长调节剂ABT(主要成分为萘乙酸和吲哚乙酸)和GGR(主要成分为吲哚乙酸),分别划分五个浓度梯度(0、10、20、30、40、50 mg‧L^(-1)),研究其对烟草幼苗根系发育的影响。随着ABT和GGR浓度的增加,烟草幼苗根系生理、根系活力和酶活性指标均呈先增加后减少的趋势。植物生长调节剂ABT和GGR均在20 mg‧L^(-1)处理时显著提升了根系活力,显著增加了烟苗的根鲜重、根长度、根表面积、根体积,提高了烟苗根系SOD、POD和CAT活性,增加了可溶性蛋白含量,降低了MDA含量。研究结果表明,ABT与GGR相比,GGR对烟草幼苗各项指标的提升效果更佳,因此在该试验条件下,推荐在实际育苗生产中,向烟草漂浮育苗营养液中添加浓度为20 mg‧L^(-1)的植物生长调节剂GGR,可大幅度促进烟苗根系发育。

In order to study the role of plant growth regulators in the process of tobacco seedling raising,and explore its influence on the root growth and development of tobacco seedlings.Two kinds of plant growth regulators ABT(mainly naphthylacetic acid and indoleacetic acid)and GGR(mainly indoleacetic acid)were added into tobacco floating seedling nutrient solution,which were divided into five concentration gradients(0,10,20,30,40,50 mg‧L^(-1))to study their effects on root development of tobacco seedlings.With the increase of ABT and GGR concentrations,the indexes of root physiology,root activity and enzyme activity of tobacco seedlings showed a trend of first increasing and then decreasing.Plant regulators ABT and GGR both significantly increased root activity,significantly increased root fresh weight,root length,root surface area and root volume,increased SOD,POD and CAT activities,increased soluble protein content and decreased MDA content in tobacco seedlings when treated with 20 mg‧L^(-1).The results show that compared with GGR,GGR has a better effect on improving various indexes of tobacco seedlings.Therefore,under this experimental condition,it is recommended that adding 20 mg‧L^(-1) plant growth regulator GGR to tobacco floating seedling nutrient solution can greatly promote the root development of tobacco seedlings.