Plant life

Plants are very important for man's life. They supply us with different food products and fibre. Domestic animals use plants as fodder.

Plants grow and develop in the soil. They obtain the necessary nutrients from the soil and air.

Minerals and nitrogen are obtained by the plants from simple salts in watery solution. Carbohydrates are synthe­sized by plants from carbon dioxide which is in the atmosphere and water. The source of energy for the process of photosyn­thesis is sunlight.

The principal parts of the plants are the root system, stems, leaves, flowers, fruits and seeds. All these parts have different functions but they are all very important for plant growth and development.

Plants may be annuals, biennials and perennials. Annual plants produce seeds the first year. Biennials produce seeds the second year. Perennials produce seeds during many years. Seeds germinate at different temperatures. The optimum tem­perature for rye, wheat, oats and barley is about 20°—25°C. In order to grow and develop well plants must have good soil and climatic conditions. They must have enough water, nutrients, heat, air and light.

One of the most important tasks of the collective farmers is to properly till the soil.

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