| People domesticate plants for the purpose of increasing the crop capacity. | ||
| Domestication of plants enables to increase yield in spite of environmental conditions. | |||
| Crop breeding can do without the genetic change of the composition of a plant. | |||
| Domestication belongs to a natural selection process under the human guidance. |
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, , , , .
People domesticate plants for the purpose of increasing the crop capacity ( ) : Domestication of plants has, over the centuries increased yield ( 酻) ( 2).
N 15
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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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People occupy themselves with crop breeding not only for yield increase but also for
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| crop plants to be tastier and more nutritious | ||
| modification of plant genetic make-up | |||
| creating high-yielding crop varieties | |||
| crops adjustment to changeable climatic conditions |
:
, , , .
People occupy themselves with crop breeding not only for yield increase but also for ( , , ) crop plants to be tastier and more nutritious ( ), .
: Domestication of plants has, over the centuries increased yield and improved the taste and nutritional value of crop plants ( ) ( 2).
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N 16
:
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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.
