Effects of Hydrogel on Growth and Antioxidant Enzymes Activities of Tobacco Seedlings under Chlorine Stress

Gao Ziting; Luo Fei; Yang Jianxin; Liu Lingling; Liu Xinyuan; Xia Maolin; Li Junying; Xu Yueqi; Ji Xiaoming

doi:10.14083/j.issn.1001-4942.2024.10.011

Abstract：To mitigate the adverse effects of chlorine stress on growth and development of tobacco seed-lings,five treatments namely CK(no KCl and hydrogel),CK1(1.15 g KCl per pot and no hydrogel),T1(1.15 g KCl+1 g hydrogel per pot),T2(1.15 g KCl+3 g hydrogel per pot)and T3(1.15 g KCl+5 g hy-drogel per pot)were set in this experiment to study the effects of hydrogel application on growth and develop-ment,antioxidant system and routine chemical constituents of tobacco seedlings under chlorine stress.The re-sults showed that the chlorine content in tobacco seedlings had a decreasing trend with the increase of hydrogel application rate,and that decreased by 21.35%and 30.62%under T2 and T3 treatment compared to CK1.The fresh weight of aboveground part,the fresh weight of underground part,the dry weight of aboveground part and the dry weight of underground part under T2 treatment increased by 16.90%,20.29%,20.00%and 30.93%respectively compared to CK1,while those increased by 27.70%,22.46%,30.77%and 37.11%un-der T3 treatment.T2 and T3 treatments increased the photosynthetic rate of tobacco seedlings by 29.23%and 41.78%respectively compared to CK1.T2 treatment decreased the catalase(CAT),peroxidase(POD)and superoxide dismutase(SOD)activities and the malondialdehyde(MDA)content by 19.30%,22.11%,12.98%and 13.25%,respectively compared to CK1,while T3 treatment decreased those by 19.91%,21.59%,21.13%and 20.33%respectively.T2 and T3 treatments effectively improved the content of nicotine,total sugar,reducing sugar and ratio of potassium to chlorine in tobacco seedlings under chlorine stress.In conclusion,the application of hydrogel could effectively alleviate the adverse effects of chlorine stress on tobac-co seedlings,and promote their growth and development.