Effect of Salt Water Stress on Seed Germination of Isatis indigotica and Analysis of Salt Tolerance Threshold

LIU Ya-hui;ZUO Yong-mei;SUN Jian-ping;Institute of Coastal Agricultural,Hebei Academy of Agriculture and Forestry Sciences,Saline and Alkali Land Greening Engineering Technology Center of Heibei Province,Tangshan Key Laboratory of Plant Salt Tolerance Research;

Salt water stress;;Isatis indigotica;;Seed germination;;Salt tolerance threshold

[Objective]To study the effect of salt water stress on seed germination of Isatis indigotica and analyze the salt tolerance threshold.[Method]Filter paper germination test was carried out to study the effects of coastal saline alkali soil on germination of I. indigotica,salt tolerance index and salt tolerance threshold in the seedling stage of I. indigotica were determined through correlation analysis and regression analysis.[Result]Germination of I. indigotica was not affected when concentration of salt water was lower than 0. 4%. The relative value of all indexes of germination were significantly inhibited when concentration of salt water was higher than 0. 6%. The relative germination rate was linearly related to salt water concentration and highly correlated. The salt tolerance thresholds of daye and lobular I. indigotica were 0. 66%,0. 73% respectively,it was evident that I. indigotica had strong salt tolerance in germination,which salt tolerance of lobular I. indigotica was higher than daye I. indigotica,it was suitable for planting in light and moderate saline alkali area.[Conclusion]The study provided theoretical basis for the selection and utilization of salt tolerant I. indigotica.