Development of tissue culture methods for the rescue and propagation of endangered Moringa spp. germplasm

Moringa is an Old-World dry tropical plant genus with great food, horticultural, industrial, and pharmaceutical potential. Although many of the thirteen known Moringa species are in danger of extinction, one species, M. oleifera Lam., is now widely cultivated. M. oleifera was therefore utilized to develop micropropagation techniques that may be applicable to the more endangered members of this genus. Immature seeds were the most responsive tissue source, and greatest success was achieved using membrane rafts and a liquid growth medium. The success rate was 73%, but the multiplication rate averaged only 4.7 shoots per culture. Most vigorous plantlet development through the transplant stage was achieved using a commercial plant preservative formulation of isothiazolones following shoot proliferation. Although there was no evidence of contamination, treatment with this microbiocide prevented early tissue senescence and it increased culture survivability.