Study on the Inducing and Browning Control of Callus Initiated from Maize Mature Embryos

Browning occurring in tissue culture of maize mature embryos restrained the induction and growth of callus and the process of cultivation.Contrast tests of silver nitrate,activated carbon,PVP and culture condition were designed to study their effects on anti-browning during the process of callus induction and subculture of maize mature embryos.The results showed that silver nitrate can control browning obviously,in which treatment of 10.0 mg/L was optimal to prevent browning of explants,and that of 7.0 mg/L was most effective to prevent callus browning.Activated carbon with concentration of 2.0 mg/L eliminated browning effectively,but inhibited callus initiation in exceeding concentration.A seven-day treatment of 2.0 g/L activated carbon after subculture initiation also eliminated browning as well as promoted the growth of callus to some extent.PVP with concentration of 1.0 g/L reduced the browning of ex-plants and promoted callus induction synchronously.In addition,cultured in dark can significantly reduce the inci-dence of browning,and is conducive to the growth of callus.