Roles of calcium in the subculture of embryogenic callus and proline accumulation induced by salt in maize

The selection experiment showed that modified N6 medium by increasing Ca 2+ content from 1 .13mmol/L to 5 mmol/L promoted obviously embryogenic callus subculture grown from maize immature embryos.During one time of subculture,the growth rate of embryogenic callus of subcultured on the medium containing 5 mmol/L of Ca 2+ increased by 0 .8 time compared with that subcultured on the medium contenting 1 .13 mmol/L of Ca 2+ .Addition of NaC1 to the N 6 subculture medium with 10g/L,the growth of embryogenic callus was inhibited significantly,and proline content increased .At the same time,addition of 5 mmol/L Ca 2+ to the N 6 subculture medium with 10g/L NaCl,the inhibition by salt was not only alleviated,but also the proline accumulation was promoted .