Production of friable callus of maize (Zea mays L.) and using the analytic hierarchy process to select an optimum culture medium

Preparation of cell suspension is an important step in the study of plant cells which is often done by the culture of friable embryogenic callus. The primary objective of this research was to produce friable callus and to determine an optimum culture medium for the induction of friable callus in maize plant. Using two basic media, Murashige-Skoog and Chu, with different concentrations of 2, 4 Dichlorophenoxyacetic acid and Benzyl adenine hormones (overall 16 different culture media), callus induction was performed on maize mature embryo explants. Selection criteria including high friable callus induction index, high callus size index, high callus fresh weight index, and low regeneration index were measured, and the mean values were compared using analysis of variance. Considering each of these selection criteria alone, different optimum media for callus induction were introduced. In order to determine one optimum medium considering all the criteria, the analytical hierarchy method was utilized. The optimum medium in this study was MS supplemented with 1 mg/L 2, 4-D wherein the induction, weight, and size indices were high, and the regeneration index was low. In order to evaluate and verify the selected medium, the explants were cultivated in in silico- selected medium and the growth curves were plotted for callus fresh and dry weights. Several successive subculturing of the callus was performed on the selected medium wherein no regeneration was observed. The results suggested the analytical hierarchy approach can be used as a reliable decision-making method for optimum-medium selection for inducing maize friable callus.