most plants can stimulate callus to them. Tissue from different parts of the plant, whether the seed embryo roots, stems, leaves or flowers can be cultured to calluses on them. The callus growth as well is embryo and cotyledon leaves. If not, tissue culture and callus tissue, it can stimulate those cells divide and build calluses using hormones. The hormone auxin is a popular option as 2,4-D and NAA or certain types of cytokinin may be used in combination with the ability to stimulate callus.