INVITRO RESPONSE OF EMBRYOS FROM DIFFERENT PROVENANCES OF PINUS-CARIBAEA VAR HONDURENSIS MORELET

The tissue culture response of embryo explants of four fast- and slow-growing provenances of Pinus caribaea var. hondurensis was investigated. Treatments included adventitious bud induction and development with benzyladenine (BA) at different concentrations and exposure periods, root induction with naphthaleneacetic acid (NAA) and indolebutyric acid (IBA) and callus production with combinations of NAA, 2, 4-dichlorophenoxyacetic acid (2, 4-D), BA and kinetin. Fast-growing provenances produced nodules earlier on the cotyledonary surface, developed shoots earlier from induced buds and produced more shoots per surviving embryo at lower BA concentrations tested compared with slow-growing provenances. On the other hand, calluses of the slow-growing provenance, La Mosquitia, grew faster on media supplemented with cytokinins and auxins compared with those grown on media supplemented with auxin only. This reaction was not observed with fast-growing provenances. It is suggested that cytokinins in fast-growing provenances promoted organized development more efficiently than in slow-growing provenances.