Embryogenic callus induction of coffee [Coffea arabica L.] on several plant growth regulator concentration and incubation temperature

Abstract

Clonal propagation using in vitro techniques to provide good quality seedling of coffee requires technological establishment, especially about the determinant factor for regeneration success. Therefore the study of regeneration methods in vitro in coffee plants needs to be done either through somatic embryogenesis or organogenesis. The purpose of this research was to obtain the optimal concentration of plant growth regulators and incubation temperatures to induce the embryogenic callus of coffee. The basic medium was used MS [Murasige and Skoog] with the addition of 1 g/L of active charcoal and 7 g/L of bactoagar. The experiment used a factorial completely randomized design. The first factor is the concentration of plant growth regulators consisting of 6 levels : 0.5 mg 2.4D L−1 + 1 mg TDZ L−1; 0.5 mg 2.4D L−1 + 2 mg TDZ L−1; 1 mg 2.4D L−1 + 1 mg TDZ L−1; 1 mg 2.4D L−1 + 2 mg TDZ L−1; 2 mg 2.4D L−1 + 1 mg TDZ L−1; 2 mg 2.4D L−1 + 2 mg TDZ L−1. The second factor is the incubation of temperature is consisting of 2 levels: 18°C and 26°C. Variables observed included: time of callus induction, percentage of callus induction, callus texture and callus color. The results showed that all medium tested only media with a concentration of 2 mg 2.4D L−1 + 2 mg TDZ L−1 which gave an optimal response to the percentage of callus induction which reached 100% with friable texture and yellowish-white. Based on observations it is also known that the incubation temperature of 26°C can induce callus faster than the incubation temperature of 18°C.