SEED GERMINATION

1.1 Epigeal germination

1.2 Hypogeal germination

1. Germination is the process by which the dormant embryo in a seed resumes growth ,       

    emergence of the radicle through testa , follow by growth of young shoot or plumule. 

2. Growth is a characteristic of all living organisms . Growth is a permanent irreversible increase     in size of an organism due to increase in its dry mass .

3. In order for the seed to germinate , the seed should imbibe / absorp water ( imbibition )      

    through micropyle and testa . 

4. Seed coat will swell and rupture .

5. Testa will break and allow seed to take in more H2O .

6. This cause oxygen available to develop embryo . 

7.  H2O is necessary to activate biochemical reactions .

8. H2O hydrolysis store food .

9. H2O dilute abscisic acid ( ABA ) in seed which act as growth inhibitors .

10. Suitable temperature , light and growth promoters are factors needed to break dormancy and 

      stimulate germination .

11. Activate embryo synthesis & release gibberellins ( plant hormone ) 

12. Germinating seedling emerges through the soil by epigeal germination or hypogeal      

      germination .