plant breeding

plant breeding,

science of altering the genetic pattern of plants in order to increase their value. Increased crop yield is the primary aim of most plant-breeding programs; advantages of the hybrids and new varieties developed include adaptation to new agricultural areas, greater resistance to disease and insects, greater yield of useful parts, better nutritional content of edible parts, and greater physiological efficiency. Other goals are adaptation of crops to modern production techniques such as mechanical harvesting and improvement in the market quality of the product.

Traditionally, plant breeders have made genetic changes in crops by using various crossing and selection methods, creating desirable hybridshybrid
, term applied by plant and animal breeders to the offspring of a cross between two different subspecies or species, and by geneticists to the offspring of parents differing in any genetic characteristic (see genetics).
..... Click the link for more information. ; breeders also now attempt to induce favorable genetic mutationsmutation,
in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any change in the delicate balance of an organism having a high level of adaptation to its environment
..... Click the link for more information. by the use of ultraviolet light, gamma radiation, or chemicals. With the development of genetic engineeringgenetic engineering,
the use of various methods to manipulate the DNA (genetic material) of cells to change hereditary traits or produce biological products. The techniques include the use of hybridomas (hybrids of rapidly multiplying cancer cells and of cells that make a
..... Click the link for more information. , plant breeders have increasingly used its techniques to introduce desirable traits (i.e., genes), often from other species, into cultivated plants.

See also breedingbreeding,
in agriculture and animal husbandry, propagation of plants and animals by sexual reproduction; usually based on selection of parents with desirable traits to produce improved progeny.
..... Click the link for more information. .

plant breeding

the science that aims to improve the quality and yield of plants by the genetic engineering of varieties. The main tool of the plant breeder is SELECTION, by which it is possible to alter the genetic constitution of a plant type, provided that genetic variability is present in the original strains. Another method of improvement is the crossing together of inbred lines to produce HETEROSIS in the hybrids (see GREEN REVOLUTION). Plant breeding has lead to a great improvement in crop yield, better harvesting (e.g. with dwarf varieties) and improvements in the natural resistance of plants to pathogens. Recently, cell and tissue cultures using EXPLANTS have begun to be used by plant breeders, to produce

(a) multiple copies (CLONES) of sterile types;
(b) the development of forms with new chromosome combinations;
(c) HAPLOIDS (2) which can be induced to become fertile DIPLOIDS (2) (the latter forming PURE BREEDING LINES).

单词	plant breeding
释义	plant breeding plant breeding, science of altering the genetic pattern of plants in order to increase their value. Increased crop yield is the primary aim of most plant-breeding programs; advantages of the hybrids and new varieties developed include adaptation to new agricultural areas, greater resistance to disease and insects, greater yield of useful parts, better nutritional content of edible parts, and greater physiological efficiency. Other goals are adaptation of crops to modern production techniques such as mechanical harvesting and improvement in the market quality of the product. Traditionally, plant breeders have made genetic changes in crops by using various crossing and selection methods, creating desirable hybridshybrid , term applied by plant and animal breeders to the offspring of a cross between two different subspecies or species, and by geneticists to the offspring of parents differing in any genetic characteristic (see genetics). ..... Click the link for more information. ; breeders also now attempt to induce favorable genetic mutationsmutation, in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any change in the delicate balance of an organism having a high level of adaptation to its environment ..... Click the link for more information. by the use of ultraviolet light, gamma radiation, or chemicals. With the development of genetic engineeringgenetic engineering, the use of various methods to manipulate the DNA (genetic material) of cells to change hereditary traits or produce biological products. The techniques include the use of hybridomas (hybrids of rapidly multiplying cancer cells and of cells that make a ..... Click the link for more information. , plant breeders have increasingly used its techniques to introduce desirable traits (i.e., genes), often from other species, into cultivated plants. See also breedingbreeding, in agriculture and animal husbandry, propagation of plants and animals by sexual reproduction; usually based on selection of parents with desirable traits to produce improved progeny. ..... Click the link for more information. . plant breeding plant breeding the science that aims to improve the quality and yield of plants by the genetic engineering of varieties. The main tool of the plant breeder is SELECTION, by which it is possible to alter the genetic constitution of a plant type, provided that genetic variability is present in the original strains. Another method of improvement is the crossing together of inbred lines to produce HETEROSIS in the hybrids (see GREEN REVOLUTION). Plant breeding has lead to a great improvement in crop yield, better harvesting (e.g. with dwarf varieties) and improvements in the natural resistance of plants to pathogens. Recently, cell and tissue cultures using EXPLANTS have begun to be used by plant breeders, to produce (a) multiple copies (CLONES) of sterile types; (b) the development of forms with new chromosome combinations; (c) HAPLOIDS (2) which can be induced to become fertile DIPLOIDS (2) (the latter forming PURE BREEDING LINES).
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