外源虾青素对盐胁迫下萝卜种子萌发和芽苗生长的影响OA

In order to explore the effect of exogenous astaxanthin(As)on radish seed germination and seedling growth under salt stress,this experiment used Jinluobo 3 as experimental material to study the effects of soaking seed with different concentrations(0.05,0.1,0.3,0.5 g/L and 1.0 g/L)of As on radish seed ger-mination and seedling growth under 150 mmol/L NaCl stress,using treatment with distilled water as control(CK).The results showed that with the increase of As concentration,the germination rate,germination poten-tial,germination index and vigor index of radish seeds under salt stress showed a trend of first increasing and then decreasing.Among them,soaking seed with 0.1 g/L As(NaCl+0.1As),the seed germination rate,ger-mination potential,germination index and vigor index were increased by 9.4%,29.3%,20.5%and 78.4%,respectively,compared with the NaCl treatment,and the relative salt injury rate was significantly reduced by 71.5%.The NaCl+0.1As treatment also significantly promoted seedling growth,and the single plant fresh weight,shoot height and root length increased by 33.8%,65.2%and 86.9%,respectively,compared with NaCl treatment.Compared with CK,NaCl treatment significantly promoted the accumulation of hydrogen per-oxide(H2 O2)and malondialdehyde(MDA)in seedling leaves and reduced cell activity of root tips,resulting in aggravated oxidative damage.The treatment with appropriate concentration of astaxanthin significantly in-creased the contents of soluble protein,phenolic compounds,ascorbic acid and glutathione in seedlings,en-hanced antioxidant activity and reduced oxidative damage caused by salt stress,among which,NaCl+0.1As treatment showed the best alleviating effect.In conclusion,exogenous As could effectively alleviate the oxida-tive damage of salt stress to radish germination and seedling growth,promote seed germination and seedling growth,and improve salt tolerance of radish seedlings.The results of this study could provide a certain theoret-ical and technical support for the application of As to improve radish resistance to salt stress.