In vitro propagation of threatened therapeutic tree Buchanania lanzan Spreng (Anacardiaceae)

Abstract

Embryo rescue refers to an in vitro technology have been used for propagating plants under in vitro from poorly developed embryos by avoiding embryo abortion. The aim of the present study was to in vitro regeneration of a medicinally wild tree species Buchanania lanzan through embryo rescue method. Isolated immature poorly developed embryo dissected out from de-coded seeds collected from 15 years old trees were cultured an Woody Plant Medium (WPM) was used to test in vitro germination. 100% embryo germination were recorded when the embryos inoculated on the medium supplemented with 1.5 mg/L-1 6-benzylaminopurine (BAP) and 50 mg/L-1 adenine sulphate (AS). Further, a week-old seedling derived explants viz embryo axis and cotyledonary node were selected to study in vitro clonal propagation. On medium augmented with 1.5 mg/L-1 6-benzylaminopurine (BAP) showed maximum mean shoots numbers (4.2±1.80) with 4.0±0.98 cm shoot height were achieved in cotyledonary node. Compare to Kinetin (Kn) BAP was to be better in shooting response and multiple shoot induction. Healthy regenerated shoots was separated from multiple shoots cluster and transferred to a rooting medium containing half strength WP medium fortified with Indole-3-butyric acid (IBA). IBA at 0.5 mg/L-1 showed 90% rooting response and maximum mean roots (4.9±0.98) per shootlet was obtained. The rooted in vitro plantlets were transferred to polythene bags containing autoclaved humus, red soil and farmyard manure (1:1:1 ratio) for acclimation at 25 ± 2 ᵒC. Later, these plantlets were gradually transferred to field condition. About 70% survival rate was recorded after three months period. The protocol developed in the present study was to restore the viable embryos from poorly developed immature embryos and rapid multiplication can help to ex situ conservation of this threatened tree B. lanzan.
 Keywords: Woody plant medium, In vitro seedlings, 6-benzylaminopurine, Adenine sulphate, Indole-3-butyric acid