EN
Callus was successfully induced from the mature endosperm of three Actinidia species: A. arguta, A. deliciosa var. deliciosa (kiwifruit) and A. kolomikta. For the initiation of callus, MS medium supplemented with 2,4-D (2 or 4 mg/l) and kinetin (5 mg/l) was used. Transfer of the callus to medium containing IAA (0.1 mg/l) and BAP (1 mg/l) resulted in the formation of roots in approximately 40% of the endosperm explants of A. deliciosa. The callus, initially yellow-white, turned green when cultured in the light. In A. arguta and A. kolomikta no morphogenic response was observed on this medium. If the cultures were inoculated onto medium with IAA (0.3 mg/l) and 2iP (5 mg/l), in the endosperm calluses of kiwifruit, shoots were formed in addition to roots. In A. arguta a few abnormal shoots were produced in one explant. The sub-culture of A. arguta callus on MS without hormone evoked the production of some roots. No morphogenic response was observed in the endosperm cultures of A. kolomikta on all media tested. The counting of chromosomes in five roots and young leaves of one shoot of A. deliciosa revealed that they were triploids with chromosome number 2n = ~250.