MORPHOGENETIC PATTERNS IN KIWI TISSUE CULTURE AND AFTER AGROBACTERIUM CO-CULTURE.

Nodal segments, petioles, and leaf blades of Actinidia deliciosa Liang and Ferguson, cv. "Hayward", were used for developing morphogenetic ways for micropropagation and breeding through induction of variability in tissue culture and Agrobacterium mediated transformation. Mineral constituents of three different defined media: MS, K(h), and St, in several concentrations and supplemented with IAA (0.025 mg/1) and zeatin (1 or 0.5 mg/l) were used. The cultures gave rise to direct and indirect morphogenetic processes, stated as axillary and adventitious shoot-buds, respectively. Axillary shoot-bud development was achieved in K(h) medium with IAA (0.025 mg/l) and zeatin (1 mg/l). Callus induction and proliferation was succesfully obtained from all of the explants used, cultured in MS medium with IAA (0.025 mg/l) and zeatin (1 mg/l). Adventitious shoot-bud formation was obtained from callus, in all of the explants assayed, cultured in K(h) medium with IAA (0.025 mg/l) and zeatin (1 mg/l). The morphogenetic callus was monthly subcultured in ½ K(h) medium with IAA (0.025 mg/l) and zeatin (0.5 mg/l) to obtain shoot-bud development. Microshoot rooting was achieved by basal immersion in IBA (1 g/l for 15 sec or 0.5 g/l for 2 min). Roots were developed in ½ K(h) hormone-free medium after 10 days. Petioles and leaf discs were successfully co-cultured with Arhizogenes strain G'746 for a 48 hour period. The infection process was then arrested and the explants cultured in ½ K(h) with IAA (0.025 mg/l) and zeatin (0.5 mg/l). Callus induction and proliferation was succesfully obtained in these conditions, with reversion of the morphogenetic pattern formerly obtained.