Growth Response of Moringa oleifera Lam. Shoot Culture to Benzyladenine and Nitrogen Modification

Abstract
In plant micropropagation, cytokinin and nitrogen are the essensial components that affect plant growth and morphogenesis. In this research, we evaluated the effect of BA concentration and modification of MS medium with variation in total nitrogen concentration and NO3-:NH4+ ratio on the growth of moringa plant. The treatments tested were (1) BA concentrations of 0.00, 0.05, 0.10, 0.25, 0.50, 1.00 mg L-1; (2) the total N concentrations of 20, 40, 60, 80 mM; (3) the NO3-:NH4+ ratio of 1:0, 1:3, 1:1, 3:1, 0:1. The experimental design used was a completely randomized design with 10 replications. The results showed that the treatment of 0.25 mg L-1 BA produced the best shoot proliferation with the highest number of nodes (8.07 ± 3.48). The shoot growth response to nitrogen level tended to be parabolic with an optimum concentration of 40-60 mM. Modification of MS medium with different NO3-:NH4+ ratio showed differences in the growth and biomass of moringa shoots, and the optimal growth was obtained at the 3:1 ratio. Therefore, MS medium with total nitrogen concentration of 40-60 mM with NO3-:NH4+ ratio of 3:1 can be used for in vitro propagation of Moringa selected genotypes. Keywords: Benzyladenine, Moringa oleifera, nitrate/ammonium ratio, shoot, total N