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Registro Completo |
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Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
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Data corrente: |
29/04/2003 |
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Data da última atualização: |
25/08/2023 |
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Autoria: |
AASTVEIT, A. H.; AASTVEIT, K. |
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Título: |
Theory and application of open-pollination and polycross in forage grass breeding. |
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Ano de publicação: |
1990 |
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Fonte/Imprenta: |
Theoretical and Applied Genetics, v. 79, n. 5, p. 618-624, may, 1990. |
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DOI: |
10.1007/BF00226874. |
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Idioma: |
Inglês |
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Conteúdo: |
Abstract: Progeny testing and selection of forage grasses by means of growing half-sib (HS) families from open-pollination and polycross have been considered from theoretical and practical points of view. Special attention has I been paid to the genetic variation within half-sib families, which is expected to be large as compared to the genetic ,i variation between families. Based on observations of individual plants within plots, the environmental component of the variation is expected to be large and nonestimatable. The results of an experiment in meadow fescue (Festuca pratensis Huds.) are presented. In this experiment, randomly selected individual plants within HS-families were cloned and laid out in randomized blocks. For the characters observed (earliness and raw matter yield) no significant variance component for dominance was found. The highly significant additive component estimated for earliness, as well as for yield, after each of three cuts and in total were about three times as large within as between families, as expected from the theoretical considerations. The estimated response to selection was much higher for a combination of between- and within-family selection as compared to free clone or family mean selection alone. It is suggested that a program for progeny testing and selection in a base population of perennial forage grasses should start with an experiment in which a large number of randomly selected parental clones and a fixed number of clones from each of the half-sib families derived from the mother genotypes are grown simultaneously. The selected clones within superior families could later on be further cloned, placed in a polycross field, and the new HS-families could be sown in ordinary field trials at various locations for further selection. MenosAbstract: Progeny testing and selection of forage grasses by means of growing half-sib (HS) families from open-pollination and polycross have been considered from theoretical and practical points of view. Special attention has I been paid to the genetic variation within half-sib families, which is expected to be large as compared to the genetic ,i variation between families. Based on observations of individual plants within plots, the environmental component of the variation is expected to be large and nonestimatable. The results of an experiment in meadow fescue (Festuca pratensis Huds.) are presented. In this experiment, randomly selected individual plants within HS-families were cloned and laid out in randomized blocks. For the characters observed (earliness and raw matter yield) no significant variance component for dominance was found. The highly significant additive component estimated for earliness, as well as for yield, after each of three cuts and in total were about three times as large within as between families, as expected from the theoretical considerations. The estimated response to selection was much higher for a combination of between- and within-family selection as compared to free clone or family mean selection alone. It is suggested that a program for progeny testing and selection in a base population of perennial forage grasses should start with an experiment in which a large number of randomly selected parental clones and a fixed number of clones from e... Mostrar Tudo |
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Palavras-Chave: |
Bootstrap; Policruzamento; Polinização aberta. |
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Thesagro: |
Gramínea Forrageira; Melhoramento Genético Vegetal; Variação Genética. |
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Thesaurus Nal: |
Forage grasses; Genetic correlation; Genetic variation; Plant genetics. |
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Categoria do assunto: |
G Melhoramento Genético |
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Marc: |
LEADER 02619naa a2200265 a 4500
001 1529305
005 2023-08-25
008 1990 bl uuuu u00u1 u #d
024 7 $a10.1007/BF00226874.$2DOI
100 1 $aAASTVEIT, A. H.
245 $aTheory and application of open-pollination and polycross in forage grass breeding.$h[electronic resource]
260 $c1990
520 $aAbstract: Progeny testing and selection of forage grasses by means of growing half-sib (HS) families from open-pollination and polycross have been considered from theoretical and practical points of view. Special attention has I been paid to the genetic variation within half-sib families, which is expected to be large as compared to the genetic ,i variation between families. Based on observations of individual plants within plots, the environmental component of the variation is expected to be large and nonestimatable. The results of an experiment in meadow fescue (Festuca pratensis Huds.) are presented. In this experiment, randomly selected individual plants within HS-families were cloned and laid out in randomized blocks. For the characters observed (earliness and raw matter yield) no significant variance component for dominance was found. The highly significant additive component estimated for earliness, as well as for yield, after each of three cuts and in total were about three times as large within as between families, as expected from the theoretical considerations. The estimated response to selection was much higher for a combination of between- and within-family selection as compared to free clone or family mean selection alone. It is suggested that a program for progeny testing and selection in a base population of perennial forage grasses should start with an experiment in which a large number of randomly selected parental clones and a fixed number of clones from each of the half-sib families derived from the mother genotypes are grown simultaneously. The selected clones within superior families could later on be further cloned, placed in a polycross field, and the new HS-families could be sown in ordinary field trials at various locations for further selection.
650 $aForage grasses
650 $aGenetic correlation
650 $aGenetic variation
650 $aPlant genetics
650 $aGramínea Forrageira
650 $aMelhoramento Genético Vegetal
650 $aVariação Genética
653 $aBootstrap
653 $aPolicruzamento
653 $aPolinização aberta
700 1 $aAASTVEIT, K.
773 $tTheoretical and Applied Genetics$gv. 79, n. 5, p. 618-624, may, 1990.
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Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
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