Table of Contents
What is Germination of Seed?
When a seed begins to germinate, the first thing that happens is the water inside the seed starts to move. This movement causes the seed coat to split open. The next thing that happens is the embryo starts to grow. The root starts to grow down into the soil and the shoot starts to grow up into the air.
Stages of Seed Germination
- Seed germination is the process that begins with the absorption of water and ends with the emergence of a seedling from the soil. The process of seed germination is controlled by the environment and by the embryo within the seed.
- The environment controls seed germination by providing water and oxygen and by moderating the temperature. The embryo controls seed germination by secreting enzymes that digest the endosperm and by controlling the growth of the root and the shoot.
- The four stages of seed germination are imbibition, germination, emergence, and seedling establishment.
- Imbibition is the process of water uptake. The water enters the seed through the micropyle and the radicle begins to grow.
- Germination is the process of the seedling emerging from the seed. The root emerges from the seed and the hypocotyl elongates.
- Emergence is the process of the seedling breaking free from the seed coat. The cotyledons open and the root and the shoot grow.
- Seedling establishment is the process of the seedling becoming established in the soil. The root grows deep into the soil and the shoot grows tall.
What is Seed Germination?
The process of a seed developing into a new plant is called germination. The seed starts to grow and the root system grows down into the soil while the stem and leaves grow up and out of the soil.
Environmental Conditions
The environmental conditions for this experiment were 20 degrees Celsius and 50% humidity.
- Germination is the process that starts with the absorption of water by a seed, followed by the activation of an embryo, and the growth of a new plant. The environmental conditions required for germination vary with different species of plants, but some general requirements include the presence of water, oxygen, and a suitable temperature.
- The water requirement is usually quite high, with most seeds needing to be completely submerged in order to germinate. Oxygen is also necessary, and most seeds will not germinate in anaerobic conditions. The temperature range for germination varies, but most seeds will germinate between 60 and 95 degrees Fahrenheit.
- Some seeds, such as those of the morning glory, have a hard outer coat that must be broken down before the seed can germinate. This is usually accomplished through natural processes such as rain or wind, or by the activities of animals or insects. Other seeds, such as those of the bean, have a soft outer coat that allows water and oxygen to easily enter.
- The environmental conditions necessary for germination are not always easy to replicate, which is why some seeds will remain dormant until the right conditions are present. For example, many seeds will not germinate if they are buried too deep in the soil, since they will not be able to reach the surface and get the water and oxygen they need.
Water Imbibition
- Water imbibition is the uptake of water by a solid material. The water can either be absorbed from the surrounding environment or be brought in from another source. The water is then held in the material by capillary action or by adsorption.
- Water imbibition can be used to moisturize materials, to stabilize soils, and to improve the strength and durability of materials. It is also used in the food industry to improve the texture and flavor of food products.
Root and Shoot Growth
- Root and shoot growth are the two main ways that plants grow. Roots grow in the soil, and shoots grow in the air. Roots grow from the tips of the plant’s stem, and shoots grow from the plant’s leaves.
- Roots grow in two ways: they can grow longer, or they can grow thicker. Shoots grow in two ways: they can grow taller, or they can grow wider.
- Roots grow by cell division. Cells at the tip of the root divide and grow longer. New cells are added to the root, and the root grows thicker.
- Shoots grow by cell division and by cell elongation. Cells at the base of the shoot divide and grow taller. New cells are added to the shoot, and the shoot grows wider.
Formation of Seedling
The seedling is the young plant that germinates from a seed. The root system of the seedling grows down into the soil, and the stem system grows up into the air. The seedling’s first leaves are called cotyledons and they are usually very small.
Conditions Required for Bean Germination
In order for bean seeds to germinate, they need darkness, moisture, and warmth. The seeds will not germinate if they are exposed to light. The seeds will not germinate if they are dry, and they will not germinate if they are cold.
