Advances in somatic embryogenesis and plant production of black locust (Robinia pseudoacacia L.).

Black locust (Robinia pseudoacacia L.) immature seeds of different developmental stages were tested for the ability to initiate embryogenic cultures. Best results (average of 12% embryogenic cultures) were obtained when seeds collected 2-3 weeks post-anthesis were cultured for 3 weeks on modified Finer and Nagasawa medium containing 2,4-D (45-90 μM) and BA (2.2 μM) and then transferred to the same medium without growth regulators. Embryo conversion was obtained from naked or encapsulated somatic embryos derived from a long-term embryogenic line. Without cold treatment, 71% of naked embryos and 41% of the encapsulated embryos converted into plants. Fifteen days of cold treatment increased conversion rates up to 95% for naked embryos and 80% for encapsulated embryos. Recovered plantlets were acclimatized and grown in the greenhouse.