The Induction of Callus in Four Diverse Black Soybeans (Glycine soja Sieb. & Zucc) with Various Combinations of Cytokinins and 2,4-Dichlorophenoxyacetinic Acid

The black soybean (Glycine soya Sieb. & Zucc) is a species of legume native of East Asia, widely grown for its edible bean, which has numerous uses. Furthermore, it is used as a raw material in the soy sauce industry, and its protein and antioxidant content is preferred to yellow soybeans. This study was conducted to evaluate the in vitro callus growth pattern of four varieties of black soybean grown in various combinations of cytokinins and 2,4-dichlorophenoxyacetic acid (2,4-D), and was performed at the Agronomy Laboratory, Faculty of Agriculture, the University of Bengkulu. A completely factorial randomized design (RAL) with 10 replications was used in this experiment. The first factor was four varieties of black soybeans, namely Detam1, 2, 3, and 4. Similarly, the second factor was the type of cytokinin, namely K0 = 0 (control / without plant growth regulators), K1 = 2 mg.L-1 BAP + 0.5 mg.L-1 2,4-D, and K2 = 2 mg.L-1 Kinetin + 0, 5 mg.L-1 2,4-D. The mature cotyledon explants were cultured on Murashige and Skoog (MS) Medium. The results showed that Detam 2, 3 and 4 black soybean varieties grown on MS + 2 mg.L-1BAP + 0.5 mg. L-12,4-D medium produced more friable callus with clear green-yellow color as compared to those grown on MS + 2 mg.L-1 Kinetin + 0.5 mg.L-1 2,4-D. The greatest compact callus with yellow-green color were formed by Detam 1 variety planted on MS medium + 2 mg.L-1 Kinetin + 0.5 mg.L-1 2,4-D. The greatest embryogenic callus production (100%), the heaviest callus fresh weight (1.53 g) and the greatest fresh culture yield (1.58 g) of yellow-green callus with friable texture were produced by Detam 3 variety grown on MS + medium 2 mg.L-1 BAP + 0.5 mg.L-1 2,4-