1. Introduction

  1. After fertilization, the ovule develops into a seed, and the ovary transforms into a fruit.
  2. This process ensures reproduction and dispersal of flowering plants.

2. Development of Seeds

  1. A seed is a mature ovule containing the plant embryo.
  2. Seed development starts after double fertilization in angiosperms.
  3. The zygote develops into an embryo, while the triploid nucleus forms the endosperm.

Parts of a Seed

  1. Seed Coat: The outer protective layer derived from the integuments of the ovule.
  2. Embryo: The developing plant, consisting of the radicle (future root), plumule (future shoot), and cotyledons (seed leaves).
  3. Endosperm: Stores food for the embryo (present in monocots but absorbed in dicots).

Types of Seeds

  1. Monocotyledonous Seeds: Have a single cotyledon (e.g., Rice, Wheat).
  2. Dicotyledonous Seeds: Have two cotyledons (e.g., Pea, Mango).
  3. Albuminous Seeds: Retain endosperm (e.g., Maize, Castor).
  4. Exalbuminous Seeds: Consume endosperm during development (e.g., Pea, Groundnut).

3. Dormancy and Germination

  1. Seed Dormancy: A period where the seed remains inactive despite favorable conditions.
  2. Caused by factors such as hard seed coat, immature embryo, or chemical inhibitors.
  3. Broken by natural or artificial means (scarification, temperature changes, etc.).
  4. Seed Germination: The process by which a seed develops into a seedling.

4. Fruit Formation

  1. A fruit is a mature, ripened ovary containing seeds.
  2. Its main function is to protect and help in seed dispersal.
  3. Fruits develop after fertilization, though some (parthenocarpic fruits) form without fertilization.

Types of Fruits

  1. Simple Fruits: Develop from a single ovary (e.g., Mango, Tomato).
  2. Aggregate Fruits: Develop from multiple ovaries of a single flower (e.g., Strawberry).
  3. Multiple Fruits: Develop from a cluster of flowers (e.g., Pineapple).

Parthenocarpy

  1. Parthenocarpy is the development of fruit without fertilization.
  2. Such fruits are seedless (e.g., Banana, Grapes).
  3. Can be natural or induced by plant hormones like auxins and gibberellins.

5. Seed and Fruit Dispersal

  1. Essential for preventing overcrowding and colonizing new areas.
  2. Wind Dispersal: Seeds are lightweight or winged (e.g., Cotton, Maple).
  3. Water Dispersal: Seeds float and have waterproof coverings (e.g., Coconut, Lotus).
  4. Animal Dispersal: Seeds stick to fur or are eaten and excreted (e.g., Mango, Tomato).
  5. Explosive Mechanism: Fruits burst open and scatter seeds (e.g., Castor, Balsam).

6. Importance of Seed and Fruit Development

  1. Ensures plant reproduction and survival.
  2. Seeds provide food and economic value (e.g., Grains, Pulses).
  3. Fruits protect seeds and aid in dispersal.
  4. Understanding these processes helps in agriculture, horticulture, and conservation.

7. Conclusion

  1. Seed development begins after fertilization and leads to embryo formation.
  2. Fruit formation occurs from the ovary and aids in seed dispersal.
  3. These processes are crucial for plant survival and agricultural production.

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