1.What are the conditions necessary for germination ?
Answers
Answer:
All seeds need water, oxygen, and proper temperature in order to germinate. Some seeds require proper light also. Some germinate better in full light while others require darkness to germinate. When a seed is exposed to the proper conditions, water and oxygen are taken in through the seed coat.
Answer:
Conditions Necessary for Seed Germination
Here are some important requirements which are essential for a seed to germinate into a seedling and to a plant.
Water:
It is extremely necessary for the germination of seeds. Some seeds are extremely dry and need to take a considerable amount of water, relative to the dry weight of the seed. Water plays an important role in seed germination. It helps by providing necessary hydration for the vital activities of protoplasm, provides dissolved oxygen for the growing embryo, softens the seed coats and increases the seed permeability. It also helps in the rupturing of seed and also converts the insoluble food into soluble form for its translocation to the embryo.
Oxygen:
It is an important and essential source of energy required for seed growth. It is required by the germinating seed for metabolism and is used as a part of aerobic respiration until it manages to grow green leaves of its own. Oxygen can be found in the pores of soil particles, but if the seed is buried too deep it will be deprived of this oxygen.
Temperature:
For a seed to germinate, it requires a moderate temperature of around 25-30°C. Quite obviously different seeds require different optimum temperatures. There are some seeds which require special requirements either lower or higher temperature between 5 to 40°C.
Light or darkness
This can act as an environmental trigger. Many seeds do not germinate until sunlight falls on them.
The process of seed germination triggers under the above mentioned favourable conditions. The seeds undergo rapid expansion and growth of the embryo and subsequently rupturing the covering layers and emergence of the radicle. This radicle emergence is considered the completion of germination.