Somatic embryogenesis from three coffee cultivars: 'Rubi', 'Catuaí Vermelho 81', and 'IAPAR 59'

Abstract

Leaf explants of Coffea arabica cv. Rubi, 'Catuaí Vermelho 81', and 'IAPAR 59' were placed onto MS basal medium with 4 μM of picloram for 8-12 weeks in the dark at 27 ± 2°C (standard temperature). Explants ('Rubi' and 'Catuaí Vermelho 81') with callus were transferred to a SP basal medium plus 0, 12, 24, and 48 μM BAP, whereas for 'IAPAR 59', only 48 μM BAP was added. After 8 weeks for 'Rubi' and 'Catuaí Vermelho 81' and after 12 weeks for 'IAPAR 59', all cultivars showed indirect embryogenesis. Embryogenic material was transferred to a SP basal medium without BAP, in light (16-hour photoperiod) and standard temperature. In a second experiment, leaf explants belonging to all three cultivars were inoculated in petri dishes with SP basal medium plus 0, 2.5 and 5 μM BAP, in the dark at standard temperature. After 8 weeks, only 'IAPAR 59' produced direct embryos. These were transferred to SP basal medium. About 30% of embryos developed abnormalities. Normal embryos were successfully transferred to soil.