Dioecious condition prevents

Options

A. autogamy
B. geitonogamy
C. xenogamy
D. both 1 & 2

Answer

**Step-by-Step Solution:**

1. **Understanding Dioecious Plants**: Dioecious plants are those that have male and female reproductive organs on separate individuals. This means that one plant will produce only male gametes (pollen), while another plant will produce only female gametes (ovules).

2. **Defining Autogamy**: Autogamy refers to self-pollination, where pollen from the same flower fertilizes its own ovules. In dioecious plants, since male and female organs are on different plants, self-pollination cannot occur.

3. **Defining Geitonogamy**: Geitonogamy is a form of pollination where pollen is transferred from one flower to another flower on the same plant. Since dioecious plants have male and female flowers on different plants, this type of pollination is also not possible.

4. **Defining Xenogamy**: Xenogamy is the transfer of pollen from one plant to the stigma of another plant, which can be genetically different. In dioecious plants, this type of pollination can occur since they have separate male and female plants.

5. **Conclusion**: Since dioecious plants prevent both autogamy (self-pollination) and geitonogamy (pollination between flowers of the same plant), the correct answer to the question is that the dioecious condition prevents both autogamy and geitonogamy.

**Final Answer**: Dioecious condition prevents both autogamy and geitonogamy.

---