Metaxenia is related to the effect of the male gamete over the seed coat of a plant. Let's understand this concept in detail.

Metaxenia is a phenomenon in which the characteristics of the pollen parent (father) influence the characteristics of the seed or fruit produced by the seed parent (mother). It occurs due to the transfer of substances from the male gametes (sperm cells) to the surrounding tissues of the ovule or embryo sac. These substances can directly or indirectly affect the development of the seed coat, resulting in changes in its characteristics.

Here is a detailed explanation of the relationship between Metaxenia and the effect of the male gamete over the seed coat of a plant:

1. Metaxenia:
Metaxenia is a Greek word that means "after-stranger" or "change with another." It refers to the phenomenon in which the characteristics of the pollen parent influence the characteristics of the seed or fruit produced by the seed parent.

2. Pollination:
Metaxenia occurs during the process of pollination, which involves the transfer of pollen from the male reproductive organ (anther) to the female reproductive organ (stigma) of a flower. The pollen contains the male gametes (sperm cells) that fertilize the egg cell in the ovule, leading to the formation of a seed.

3. Influence on the seed coat:
During fertilization, the male gametes release substances that can have an impact on the surrounding tissues of the ovule or embryo sac. These substances can affect the development and characteristics of the seed coat, which is the protective outer covering of the seed.

4. Changes in seed coat characteristics:
The substances released by the male gametes can influence the thickness, color, texture, and other physical properties of the seed coat. For example, if the pollen parent has a red pigment, it can result in a seed coat with a reddish color. Similarly, the thickness of the seed coat can be influenced by the pollen parent's characteristics.

5. Examples of Metaxenia:
Metaxenia has been observed in various plants. For instance, in some varieties of watermelon, the pollen from a sugar baby watermelon plant (with a sweet taste) can result in seeds that produce sweeter fruits compared to seeds produced by other pollen sources.

In conclusion, Metaxenia is a phenomenon in which the characteristics of the pollen parent influence the characteristics of the seed or fruit produced by the seed parent. Specifically, it is related to the effect of the male gamete over the seed coat of a plant. The substances released by the male gametes can influence the physical properties of the seed coat, such as its thickness and color. This phenomenon has been observed in various plant species and has implications for seed and fruit quality.