PLANT-GROWTH REGULATOR-INDUCED XYLOGENESIS IN COTYLEDONS OF SOLANUM AVICULARE

Treatment of explanted cotyledons of Solanum aviculare with 2,4-dichlo rophenoxyacetic acid and 6-benzylaminopurine results in the transforma tion of the mesophyll cells into tracheary, sclereid-like and vessel x ylem elements. The initial programming for xylogenesis can be achieved with as little as 10 h exposure to the plant growth regulators when e ndogenous auxin levels remain relatively high. The externally applied growth regulators would appear to enter the cotyledons both from the c ut end and via the adaxial epidermis.