Effects of exogenous melatonin on growth of radish seedlings under salt stress
Soil salinization seriously restricts the efficient production of radish.Melatonin(MT),as a natural antioxidant,plays an important role in responding to plant non-biological stress.Mantanghong radish was used as experimental materi-al to be sprayed by MT with concentrations of 0,50,100,150 and 200 μmol·L-1,respectively,to screen the best MT concentration for radish growth.Then,a matrix pot was used to irrigate radish with 200 mmol·L-1 NaCl as salt stress envi-ronment,spray radish with 0 μmol·L-1 MT(T1)and the optimal MT concentration(T2)solution as treatment group,and control group(CK)was used between non-salt stress and non-spray MT.The results showed that compared with CK,salt stress significantly decreased the plant height(except 29 d after planting),stem diameter,leaf length and leaf width(except 29 d after planting)of radish seedlings.Spraying 150 μmol·L-1 MT could increase the plant height,stem diame-ter,plant width,leaf length,leaf width and chlorophyll content of radish seedlings on 25 days after implantation.The activity of SOD and CAT was increased,and the content of MDA was decreased.On 29 days after implantation,compared with 150 μmol·L-1 MT and 0 μmol·L-1 MT,plant height,stem diameter,leaf length,leaf width and chlorophyll content increased by 26.79％,28.16％,16.81％,29.11％and 7.72％,respectively.SOD and CAT activities were significantly increased by 32.12％and 40.76％,respectively,and MDA content was significantly decreased by 38.92％,indicating that spraying 150 μmol·L-1 exogenous MT could effectively alleviate the damage of salt stress on radish seedlings and pro-mote the growth of radish seedlings.
万方数据
维普
