A reliable method of rooting shoots from mature micropropagated Pinusradiata D. Don has been developed. At the beginning of the research, difficulty in achieving consistent results was experienced. At the end of the series of described experiments, high rooting percentages (78%) were attained. The condition of shoots is important. Shoots that had been cold-stored prior to rooting did not survive. Best rooting was obtained in a free-draining peat–pumice–perlite medium in propagation trays maintained under controlled environmental conditions. A well-managed watering regime and the gradual conditioning of shoots from the day of setting enhanced survival and rooting. Removal of basal callus from shoots prior to an auxin treatment significantly improved survival (30–70%) and rooting (16–56%). A further improvement was made by providing a 5 week prerooting treatment of nutrient medium containing 6% sucrose. This pretreatment was particularly effective for one difficult to root clone. Shoots formed vigorous plantlets which were successfully acclimatised to full sunlight within 4–6 weeks of transfer to root trainers. Plantlet survival ranged from 90 to 100%.
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