Seeds are dormant forms of life of most plant. They are the products of fertilization of male and female gametes from plants. From seeds seedling and plant sprout out spontaneously under appropriate conditions. The seed is the way plants propagate their offspring. Some of them fall near the plant while some are carried over by winds, animals etc to far off places. But where ever and whatever, the method of germination of seed is always the same for a particular plant.
Stages involved in plant seed Germination :
Factors affecting germination of seeds:
Seed germination is affected by many factors like
Rains /water supply, climate, season, predators, infection to seeds, fertility of soil, temperature, sun light, Oxygen etc. Among them, rains, water supply, soil fertility, temperature at optimum levels favor germination while predator, rough climates inhibit seed germination.
Water: Seeds are most driest forms and they require water for germination. It helps seed in
- Activation of enzymes to digest reserve food
- To rupture seed coat
- To mediate all the physiological processes of seed.
- Soil temperature for seed germination is critical. Both low temperatures and high temperatures are not suitable for seed growth. Because enzymes are not active at low temperatures and physiology of growth is slow while at high temperatures they get denatured.
- Oxygen is vital to oxidize reserve food and provide energy for seed germination. Without oxygen seed do not germinate as seen in seeds sown very deep in the soil.
- Seed germination varies in plants due to light. Some require light for germination while in other germination is inhibited by light. But light seems to guide direction of roots and stem from the seed.
- Seeds germinate immediately after being sown. But some seeds stay inactive in the soil for some time period and then go for germination. This period of rest is called seed dormancy.
Seeds ability to germinate varies on the method of storage, health of the parent, age of seed, maturity of seed, infections etc. So the seeds with good viability germinate faster.