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| Plant Breeding |
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| Crop production can be improved by breeding new varieties of crops having higher yield. The main aim of plant breeding is to produce new crops superior to the existing ones. By this method new varieties of crops, having higher yield, resistant to pests and disease can be grown. Hence, plant breeding can be defined as a science as well as art of improving genetic make-up of plants in relation to their economic use. The various approaches used for genetic improvement of crop plants are referred to as plant breeding methods or techniques. |
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| Introduction |
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| The process of introducing new plants from the place of their cultivation to a place with different climate is termed as plant introduction. The adjustment of such plants to this new locality is called acclimatization. The new crops are introduced in the form of seeds, bulbs or cuttings. This is an easy and rapid method for crop improvement. |
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| Several plants have been successfully introduced to India and they have got well adapted to the new climatic and soil conditions. |
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| Example |
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Groundnut was introduced from Philippines. |
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Cinchona was introduced from Peru. |
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Papaya was introduced from West Indies. |
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Potato was introduced from South America. |
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Date-palm was introduced from Brazil. |
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| Selection is an important technique in plant breeding. It involves picking the healthiest and the best ones out of the entire crop and reproducing them under controlled conditions. |
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| Hybridisation is the technique of introducing characters of two desirable plants into a single offspring (hybrid) by means of artificial pollination. This involves crossing of genetically dissimilar plants. |
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Intervarietal hybridization (between two different varieties) Most of the hybrid varieties of cereals have been evolved by this type of hybridization. The hybrid varieties thus evolved give good yield, are resistant to disease, are of better quality and have higher nutritive value. |
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Interspecific hybridization (between two species of the same genus) |
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| Several disease, pest and drought resistant varieties of wheat, tomato, sugarcane have been evolved by this method. |
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Intergeneric hybridization (between two plants belonging to two different genera) |
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| This type of hybridization is more for scientific interest than for any other use. Raphonobrassica, Rabbage, Triticale, Sugarcane-sorghum (jowar) are some examples of this type of crossing. |
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| Improved varieties of some important crops |
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| Activity |
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| Visit an agricultural institute where hybridization is done and study how |
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Plants are grown in artificial conditions. |
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Artificial cross-pollination is done. |
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Tissue culture is done. |
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