Question

Papaya plants exhibit xenogamy only. Why?

Answer 1

Hint: Xenogamy is the type of pollination where the transfer of pollen from one flower takes place to the stigma of the flower of another plant. The characters that facilitate cross-pollination are herkogamy, dichogamy, self-incompatibility, and male sterility. Fertilization takes place on a genetically different plant resulting in the production of genetically modified plants and hence proving to be beneficial. Cross-pollination includes various biotic and abiotic agents for the pollination.

Complete answer:
- The flower is the sexual organ of angiosperms. The male part of the flower is stamen, which contains anther and filamentous. The pistil is the female part of the flower, which contains stigma, style, and ovary.
- Unisexual flowers contain pistil and the stamens in separate flowers, enhancing cross-pollination. Bisexual flowers contain both pistil and stamens in the same flower, enhancing self-pollination.
- Plants use two abiotic (wind and water) and one biotic (animal) agent to achieve pollination.

The majority of plants use biotic agents for pollination.
- Anemophily: The pollination occurred by the effect of wind as an agent.
- Hydrophily: The pollination occurred by the effect of water as an agent in hydrophytes.
- Zoophilia: The pollination occurred by the effect of animals as an agent.
- Papaya is a unisexual plant. In this, the male and female flowers are present on different plants.
- Xenogamy (In Greek xenos=stranger, gamos=marriage) is the deposition of pollen grains from the anther of one flower to the stigma of a genetically different flower of the same species.
- Xenogamy can be pollinated by external pollinating agents and it is a type of cross-pollination.
- They produce genetically modified organisms and are capable of producing beneficial organisms.
- Excess force should be generated to be pollinated by external pollinating agents.
- Xenogamy promotes genetic variability and vitality within a breeding population by reducing the homozygosity.
- In xenogamy, flowers contain brightly colored petals, scents, and nectar for attracting insects.

Note: Papaya is a dioecious flower in which the male and female flowers are formed on different plants. Xenogamy is a fundamental part of natural selection by producing new and varied genetic combinations as an essential element of evolution. Several different adaptations of cross-pollinating flowers itself prevent cross-pollination.