Callus induction and plant regeneration from maize mature embryos.

Calli were induced from mature embryos of maize (Zea mays L.) inbred lines A632, B73 and Mol7 on MS medium supplemented with 1-2 mg/1 2,4-dichlorophenoxyacetic acid. Callus induction frequency ranged from 23-100%, with Mol7 having the highest frequency. Plants were regenerated from 4-5% of the B73 and Mol7 explants. Embryogenic and organogenic calli of B73 were maintained for more than two and one half years without losing regenerability. Of 95 regenerated plants, only one R0 plant with abnormal pollen was detected, and no morphological variants were observed in the R1 progeny.