Improving in vitro shoot growth of Moringa oleifera Lam. using temporary immersion bioreactors

Moringa oleifera is a medium-sized tree used as a food source as well as a medicinal plant since ancient times to symptoms of various ailments which range from flu to diabetes and cancer. Because of its commercial value, research on its in vitro mass production properties, could be valuable. This study tested the effect of temporary immersion systems (TIS) on the growth of M. oleifera microcuttings. TIS is known to improve the growth of plants in vitro because of improved aeration and nutrient uptake in other crops. Microcuttings were made from in vitro-grown seedling material and planted onto a pre-culturing solidified Murashige and Skoog (MS) medium containing different concentrations of 6-benzylaminopurine (BA). The microcuttings consisted of the first two lateral nodes, with the apical nodes removed. The different concentrations of BA included a control of 0, 0.1 and 0.2 mg L-1 BA. The cultures were grown on the pre-culturing media for 2 weeks and were then transferred to shooting media either in TIS bioreactors or onto a solidified medium, all containing 0.1 mg L-1 BA. The cultures were harvested after 6 weeks of growth on the shooting media, and growth parameters were statistically analyzed using ANOVA and Tukey's test. It was found that TIS resulted in increased amount and length of shoots produced per explant as well as increased shoot and callus fresh weight. With the increase in BA concentrations, growth decreased, which may indicate a sensitivity of M. oleifera to plant growth regulators (PGRs). Improving the protocol to produce moringa tissues in TIS will significantly enhance production.