Seed is the outcome of sexual reproduction in flowering plants. It represents the beginning of a new generation. A Seed is defined as a fertilized mature ovule that possesses an embryonic plant, stored food material and a protective coat.
Factors affecting seed germination
Essential environmental factors for seed germination are;
- Oxygen content; for germination, oxygen is needed in large quantities. The Seeds obtain this oxygen from the air contained in the soil. Seeds sown deeply in soil, fail to germinate because of lack of oxygen. Ploughing aerates the soil and helps in good germination. Respiratory rate of Dormant Seeds is very low so they require less amount of oxygen.
- Temperature; Germination can take place over a wide range of temperature (5 – 40o C), but the optimum for most of the crops is between 25o C to 30o C
- Moisture content or water; Water makes the Seed coat soft, causes it to rupture after swelling and start Germination. Water is also needed to bring in the dissolved oxygen for use by the growing embryo. In Dormant Seeds water content is 10-15% and is normally dehydrated, so the Dormant Seed have to absorb water to become active and for its germination.
- Light; Light has varied effects on germinating Seeds of different plants. Some Seeds need light for Germination, while in some Seeds Germination is hindered by light (i.e. Short day plants and long day plants).
Seed Germinator
A seed germinator is laboratory equipment which is used for the Germination of Seeds. Using Seed Germinators, varying atmospheric conditions can be created within the chambers without the need of going outside. Typically, these create an environment in which light, humidity and temperature are controlled to provide optimum conditions for the germination of seeds. They are made of double walled structure having two chambers, one inner and one outer. The main components of a Seed Germinator include;
- A germinating cylinder
- A temperate controller
Seed Germinators are designed in such a way that they are able to control the crucial environmental parameters.
Seed germinators can be of various types
- For research purpose there are research Seed Germinators
- There are economical germinators that are used as sprouters in different tissue culture industries and agro based industries
Apart from the usual germination applications, these Seed Germinator are also used for other testing application involving a plants, tissues, microorganism, electronic components etc.
Seed Germinators are also used in
- Enzyme reaction studies
- Tissue culture application
- Growth observation studies
- Fermentation analysis