In vitro micrografting of cashew (Anacardium occidentale L.)

SummaryThe requirements for in vitro micrografting Anacardium occidentale L. are described. Excised embryos germinated in vitro were used as rootstocks. Shoot tips and axillary shoots proliferated from seedling shoots were the source of scions. Flooding the cut surfaces immediately in a mixture that contained citric acid controlled oxidative browning. Firm contact between the scion and rootstock was assured through the use of an aluminium foil tube at the graft junction. An indole acetic acid pretreatment of the scions and a culture medium with alpha naphthalene acetic acid that enhanced rooting brought about graft fusion and development, indicating an exogenous auxin requirement. Further improvement of this technique and modifications to suit mature tree explants would prove to be a more advantageous practical application of in vitro micrografting in the improvement of cashew.