FACTORS AFFECTING CALLUS FORMATION FROM EMBRYOS OF BARLEY (HORDEUM-VULGARE)

The factors affecting callus formation from mature seed embryos of barley were investigated by comparing the responses of a number of different varieties to various auxin and cytokinin concentrations and ratios. Callus formation was induced by the auxin 2,4-D and callus growth was related to 2,4-D concentration. Varieties differed in callus forming ability as a result of differences in responsiveness to 2,4-D. Response to 2,4-D was also influenced by the growing conditions of the plants from which the seed embryos were harvested. Cytokinins were either without effect or were inhibitory to callus growth depending on variety and concentration. There were no auxin : cytokinin interactions affecting either callus growth or differentiation of established cultures. © 1979 Elsevier/North-Holland Scientific Publishers Ltd.