In vitro culture of zygotic embryos and acclimatization of green dwarf coconut palm

Abstract

The objective of this work was to improve the protocols for culture and acclimatization of green dwarf coconut palm (Cocos nucifera L.). Mature zygotic embryos, cultivated in vitro aseptically in Y3 liquid medium culture, supplemented with 27.8 mg L^-1 of Fe₂SO₄.7H₂O and 60 g L^-1 of sucrose, presented higher germination and normal plantlets formation. The plantlets transferred to Y3 semi-solid medium culture supplemented with 1 mg L^-1 of ANA, 0.5 mg L^-1 of BAP and 2.5 g L^-1 of activated charcoal, promoted better root and shoot development. In the acclimatization phase, the 1:1 substrate composed of washed sand and coconut coir dust provided higher survival of plantlets (58.33%), larger growth of the aerial part (39.08 cm) and larger number of leaves (6.33). The established protocols for in vitro culture of zygotic embryos and acclimatization of green dwarf coconut palm plantlets can be applied to germplasm exchange and conservation.