Question

I want the advantages of Self pollination and Cross pollination

Answer 1

in self pollination one plant needed
in cross pollination New species will come sometime

Answer 2

Self pollination

Self-pollination can be an advantage when the number of flowers is small or they are widely spaced.

During self-pollination, the pollen grains are not transmitted from one flower to another. As a result, the wastage of pollen is less.

Cross pollination

It helps in mixing of traits, i.e. it helps in bringing about variations. . . . Also, in repeated self pollination ,the harmful recessive traits get a chance to express themselves in the plant. This is avoided by cross pollination.