Effects of hormones on seed germination of Euscaphis konishii

【Objective】The role of hormones in seed germination of Euscaphis konishii and its relationship with reac-tive oxygen species were explored to provide an important theoretical basis for its seed dormancy breaking technology and efficient seedling breeding technology.【Method】E.konishii seeds with 210 d natural stratified were used as materials,outer hard seed coat was removed,a 12 d germination experiment was conducted.The changes of germination rate,active oxygen,antioxidant substances,plant hormones,soluble sugar and soluble protein contens under pure water,different con-centrations of gibberellin(GA₃)(20,40 and 60μmol/L) and abscisic acid(ABA)(10,20 and 30μmol/L)were measured,and germination morphology of seeds was observed.【Result】The germination rate of pure water treatment was 77.8%,the germination rate of GA₃ treatment was up to 82.2%,the germination rate of ABA treatment did not reach 50.0%,and the germination rate of pure water treatment with hard seed coat was only 17.8%.The three concentrations of GA₃ treat-ments could effectively shorten the time when germination rate reached 50.0%(T₅₀) and promote root and stem growth,but the final germination rate was not significantly different from that of pure water treatment(P>0.05).ABA treatment could effectively inhibit the germination of E.konishii seeds.The higher the concentration of ABA,the stronger the inhibi-tion.Correlation analysis showed that the germination rate was significantly positively correlated with GA₃,brassinolide(BR) and jasmonic(JA) at 8 and 12 d(P<0.05,the same below),superoxide anion(O₂^-·) was negatively correlated with BR and JA contents,and significantly positively correlated with catalase(CAT),ABA,ABA/GA₃.【Conclusion】Adding GA₃ can effectively shorten the time of the seed germination rate of E.konishii to reach 50%and promote the growth of root and stem.The accumulation of O₂^-·and ABA inhibit seed germination and the promotion of BR and JA on seed germi-nation in E.konishii may be related to the removal of O₂^-·.