Explain the two types of pollination and write the advantages and the disadvantages of the types of pollination.

Explanation

The two type of pollination are,
(a) Self-pollination: The transfer of pollen grains from the anther to the stigma of same flower or another flower borne on the same plant is called self-pollination. eg. Hibiscus. Self-pollination s also called Autogamy.
Advantages of self-pollination:
(i) Self-pollination is possible in certain bisexual flowers.
(ii) Flowers do not depend on agents for pollination.
(iii) There is no wastage of pollen grains.
Disadvantages of self-pollination:
(i) The seeds are less in numbers.
(ii) The endosperm is minute, so the seeds produce weak plants.
(iii) New varieties of plants cannot be produced.
(b) Cross-pollination: The transfer of pollen grains from the anthers of a flower to the stigma of a flower on another plant of the same species is called Cross-pollination. eg. Apples, Grapes, Plum.
Advantages of Cross-pollination:
(i) The seeds produced as a result of cross-pollination, develop and germinate properly and grow into better plants.
(ii) Cross-pollination leads to the production of new varieties.
(iii) More viable seeds are produced.
Disadvantages of Cross-pollination:
(i) Pollination may fail due to distance barrier.
(ii) More wastage of pollen grains.
(iii) It may introduce some unwanted characters.
(iv) Flowers depend on the external agencies for pollination.