Callus tissue isolated from fertilized ovules of P. tomentosa showed a persistent embryogenic capacity when cultured on Murashige and Skoog medium with 2,4-D, kinetin and casein hydrolysate. The histological examination showed that embryos had probably developed from single cells. Many embryos eventually grew into plantlets. A second isolate of an embryogenic callus was obtained from a zygotic embryo in the presence of IAA, but that strain could not be maintained in culture for more than three months.