This is Osisi Nkwu (Palm tree), nothing embedded in this tree is useless to the Igbos, every component of Osisi Nkwu is useful and most of them symbolic, it is regarded as tree of life and an economic tree, every aspect of it is lively, productive and useful, nothing goes to waste with Nkwu.
Just as Oji (Cola Nut) and Ji (Yam) are very significant and symbolic to the Igbo people, Nkwu tree (Palm tree) is equally very significant and symbolic to the Igbos.
While the yam is mostly associated with the men, Palm trees are mostly associated with women. Men farm their yam, women are known for cultivating the Palm tree.
Family and marriage institution are very important in the Igbo community, initiating and consummating marriage and wedding amongst the Igbos can be rigorous and goes in phases. But the Igbo ancestors carefully chose Nkwu (Palm tree) as a symbol of marriage and wedding ritual. Hence it’s called Igba Nkwu Nwanyi or Ibu Mmanya Nwanyi etc. They could’ve chose omu nkwu for the bride to hand over to the groom, or the igu nkwu or the nkporo nkwu, but they chose the Mmanya Nkwu. It comes from the inside, from the fabrics of the tree, signifying and symbolising the the inner self no one can reach but you. It is white, which signifies purity (Nkwu Ocha), above it all it is natural.
So the act of a bride searching for the groom to offer a drink, is significant and the content of the iko (cup) is equally symbolic. I still stick with the choice of the Igbo ancestors for Mmanya Nkwu (Palm wine) because the bride is symbolically offering the groom, her purest form, her natural being, her innermost part, and together as husband and wife they will bloom and blossom like the Palm tree, their union will not know no waste, every component and aspect of their union and family shall be useful, resourceful and productive just as Osisi Nkwu is.