The Fruits

In July single achene with seed removed

" vertical section of the fruit

When a pollen grain germinates on a stigma it produces a tube which grows down the style and effects fertilization of one ovule in the ovary. The fertilized ovule develops Into a seed and the ovary wall enlarges to become the fruit.

There are two main types of fruits:

  1. Dry. The ovary wall becomes more or less dry and hard.
  2. Indehiscent fruits do not open at maturity and usually contain a single seed. The fruit is dispersed as a whole and may be an achene with a thin leathery wall or a nut with a relatively hard woody wall. Some dry indehiscent fruits are winged (Elm).
  3. Dehiscent fruits open as they dry out and the seeds are released. A pod (Laburnum) originates from a single carpel whereas a capsule (Paulownia) is formed from two or more fused carpels.
  4. Succulent. The ovary wall is fleshy and the seeds are released when it decays or is eaten. In a berry the whole wall is fleshy but in a drupe (Cherry) the seed is enclosed in a woody layer. In other succulent fruits the receptacle (Apple) or inflorescence axis (Fig) becomes fleshy.

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