Use of bioreactors RITA? in the propagation of Pinus patula Schiede ex Schltdl. & Cham.

The objective of the present work was to evaluate the efficacy of use of the RITA (R) temporary immersion system in the large-scale propagation of P. patula. The effects of four concentrations (0.00 mu M, 4.50 mu M, 9.00 mu M, and 13.51 mu M) of 6-benzylaminopurine (BAP) on 10 hypocotyl explants were studied using a completely randomised design with three replicates per treatment. Five hypocotyl explants were grown in 250 mL RITA (R) containers of Woody Plant Culture Medium (WPM) supplemented with 20 g center dot L-1 sucrose and 10 mg center dot L-1 vitamins from Murashige and Skoog (MS) culture medium. The frequency of immersion of the explants into the culture medium was 2 min every 8 hours. The number of adventitious buds and calli formed, as well as shoot growth, were evaluated after 6 weeks of in vitro culture. The 4.50 mu M concentration of BAP was the best treatment for shoot production (5 shoots per plant) and shoot length (1.32 cm). These results could help the widespread vegetative propagation of this important forest species.