Callus induction of Calotropis gigantea using BAP and 2,4-D in vitro

Calotropis gigantea is a plant not widely used but has potential as a medicinal plant. The phytochemical compound can be produced faster using a tissue culture and a combination of growth regulators. The research objectives were to study the effect and determine the best concentration of BAP and 2,4-D in callus induction of Calotropis gigantea. This research was carried out in the Plant Physiology and Biotechnology Laboratory, Faculty of Agriculture, Sebelas Maret University, from September to November 2021. A month-old Calotropis gigantea stem was used as an explant. The research used three replicates of a completely randomized design with 25 combination treatments. The culture medium was MS with BAP (0; 0.5; 1; 1.5; 2 ppm) and 2,4-D (0; 0.5; 1; 1.5; 2 ppm) supplements. Parameters observed in this research were callus formation time, callus colour, and callus texture. The results showed that a combination of BAP 0.5 ppm + 2,4-D 1.5 ppm could induce callus faster than other treatments, 6 days. Callus morphology with green color and compact texture resulted from a combination of BAP 1.5 ppm + 2,4-D 1.5 ppm treatment.