Double fertilisation was discovered by

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The two gametes released by the pollen tube move in opposite direction most probably the streaming currents of cytoplasm. One gamete fuses with egg called fertilisation and second fuses with two polar nuclei called triple fusion i.e. fertilisation and triple fusion jointly called double fertilisation. It was first observed by Nawaschin (1848) in Lilium and Fritillaria. This phenomenon is unique to angiosperm.