Callus Initiation, Maintenance and Plant Regeneration from Embryos of Sweet Maize
Zhou Hong-sheng Institute of Crop Breeding and Cultivation, CAAS, Beijing, 100081
Immature and mature embryos of various kernel types of sweet maize (Zea maysL.) were cultured on duncan's medium and Armstrong and green's medium. All typesformed pale-yellow to yellow callus on the two media. Experiment results indicatedthat callus initiation was chiefly controlled by nucleus and kinds of medium, althoughthere were some differences between reciprocal crosses indicating cytoplasmic effect. Theorder of callus initiation percentage of different types of sweet maize was su, sh_2, suse.No difference was found between immature embryos and mature embryos on AGmedinm. In order to overcome the difficulty of maintaining callus, a new medium,MSZ was developed. It seemed to be suitable to maintain all the cultures. Two out ofthe fourteen embryo callus generated seedlings. Seedlings were transplanted into soildirectly when they were 10cm high and having 2--3 rootlets. 80% of them survivedand developed into healthy normal plants.