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.