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Crop alteration and biotechnology
1. Crop alteration has been practiced by humankind for thousands of years, since the beginning of civilization. Altering crops through breeding practices changes the genetic make-up of a plant to develop crops with more beneficial characteristics for humans, for example, larger fruits or seeds, drought-tolerance, or resistance to pests.
2. Crop breeding includes techniques such as plant selection with desirable traits, self-pollination and cross-pollination, and molecular techniques that genetically modify the organism. Domestication of plants has, over the centuries increased yield, improved disease resistance and drought tolerance, eased harvest and improved the taste and nutritional value of crop plants.
3. Careful selection and breeding have had enormous effects on the characteristics of crop plants. The green revolution popularized the use of conventional hybridization to increase yield many folds by creating «high-yielding varieties». For example, average yields of corn (maize) in the USA have increased from around 2.5 tons per hectare (t/ha) (40 bushels per acre) in 1900 to about 9.4 t/ha (150 bushels per acre) in 2001. Variations in yields are due mainly to variation in climate, genetics, and the level of intensive farming techniques.
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What technique of artificial crop breeding is proved in a practical manner?
For thousands of years, since the beginning of civilization people try to increase crop yield by intensive farming techniques.
Domestication of plants can be affected by some unpredictable factors, for example, negative influence of environment.
People have practiced the technology of crop alteration for thousands of years, since they began to grow crop in large scope.
Molecular technique that genetically modifies the plant enables to grow crops with more beneficial characteristics.
