Seed Germination Unit 8 Plant growth and Development

Seed Germination Unit 8 Plant growth and Development and Unit 17 Supervise Plant propagation

Structure of Powerpoint • Topic 1. 2: germination • Know the requirements of seeds for germination; • Understand the following factors with relation to the germination of seed: • • viability • • seed structure • • dormancy and methods of breaking dormancy

What part of the flower turns into a seed?

There are three basic parts of a seed in the angiosperms: • an embryo, • a food storage or nutritive tissue, • seed covering.

Outside of the seed • • • Testa (Posh name for seed coat Micropyle (the small pore in a seed that allows water absorption Hilum (the scar on a seed coat at the location where it was attached to the plant's stalk during development)

Inside of seed

How would we define seed dormancy? • True dormancy or innate dormancy is caused by conditions within the seed that prevent germination under normally ideal conditions What other process isn't inhibited from taking place?

How do we break seed Dormancy?

Stratification happens in Nature All we are trying to do is replicate these natural condition in your propagation systems Stratification is a process of treating seeds to simulate natural conditions that the seeds must experience before germination can occur

Cold stratification

Warm stratification

Warm stratification

Scarification Not this type of Scarification

Scarification

Scarification • What are the environmental conditions? Chemical scarification-There are chemicals inside the fruit that inhibit the seed from germinating. The fruit is digested within the stomach of the bird. The bird will then excrete just the seeds onto the ground. With the fruit digested and the inhibiting chemical gone, the seeds are able to now germinate ( when environmental conditions allow!)

Scarification

Stratification and scarification are both type of Pre-treatment • Seed pre-treatment is anything that you do to the seed before you plant them. This includes soaking, changing temperatures to mimic winter, or even keeping them in the dark. Each type of seed has a specific pre-sowing process that will over come dormancy, and allow germination to take place