Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
Tipo de documento
Assunto da revista
País de afiliação
Intervalo de ano de publicação
1.
Theor Appl Genet ; 136(4): 74, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36952013

RESUMO

KEY MESSAGE: For genomic selection in clonally propagated crops with diploid (-like) meiotic behavior to be effective, crossing parents should be selected based on genomic predicted cross-performance unless dominance is negligible. For genomic selection (GS) in clonal breeding programs to be effective, parents should be selected based on genomic predicted cross-performance unless dominance is negligible. Genomic prediction of cross-performance enables efficient exploitation of the additive and dominance value simultaneously. Here, we compared different GS strategies for clonally propagated crops with diploid (-like) meiotic behavior, using strawberry as an example. We used stochastic simulation to evaluate six combinations of three breeding programs and two parent selection methods. The three breeding programs included (1) a breeding program that introduced GS in the first clonal stage, and (2) two variations of a two-part breeding program with one and three crossing cycles per year, respectively. The two parent selection methods were (1) parent selection based on genomic estimated breeding values (GEBVs) and (2) parent selection based on genomic predicted cross-performance (GPCP). Selection of parents based on GPCP produced faster genetic gain than selection of parents based on GEBVs because it reduced inbreeding when the dominance degree increased. The two-part breeding programs with one and three crossing cycles per year using GPCP always produced the most genetic gain unless dominance was negligible. We conclude that (1) in clonal breeding programs with GS, parents should be selected based on GPCP, and (2) a two-part breeding program with parent selection based on GPCP to rapidly drive population improvement has great potential to improve breeding clonally propagated crops.


Assuntos
Melhoramento Vegetal , Seleção Genética , Melhoramento Vegetal/métodos , Genoma , Genômica/métodos , Endogamia , Produtos Agrícolas/genética , Modelos Genéticos
2.
Plant Cell ; 23(10): 3853-65, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22039214

RESUMO

Legume GRAS (GAI, RGA, SCR)-type transcription factors NODULATION SIGNALING PATHWAY1 (NSP1) and NSP2 are essential for rhizobium Nod factor-induced nodulation. Both proteins are considered to be Nod factor response factors regulating gene expression after symbiotic signaling. However, legume NSP1 and NSP2 can be functionally replaced by nonlegume orthologs, including rice (Oryza sativa) NSP1 and NSP2, indicating that both proteins are functionally conserved in higher plants. Here, we show that NSP1 and NSP2 are indispensable for strigolactone (SL) biosynthesis in the legume Medicago truncatula and in rice. Mutant nsp1 plants do not produce SLs, whereas in M. truncatula, NSP2 is essential for conversion of orobanchol into didehydro-orobanchol, which is the main SL produced by this species. The disturbed SL biosynthesis in nsp1 nsp2 mutant backgrounds correlates with reduced expression of DWARF27, a gene essential for SL biosynthesis. Rice and M. truncatula represent distinct phylogenetic lineages that split approximately 150 million years ago. Therefore, we conclude that regulation of SL biosynthesis by NSP1 and NSP2 is an ancestral function conserved in higher plants. NSP1 and NSP2 are single-copy genes in legumes, which implies that both proteins fulfill dual regulatory functions to control downstream targets after rhizobium-induced signaling as well as SL biosynthesis in nonsymbiotic conditions.


Assuntos
Lactonas/metabolismo , Medicago truncatula/fisiologia , Oryza/fisiologia , Sinorhizobium meliloti/fisiologia , Simbiose , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Carotenoides/análise , Carotenoides/metabolismo , Regulação para Baixo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Lactonas/análise , Lactonas/química , Medicago truncatula/genética , Medicago truncatula/crescimento & desenvolvimento , Medicago truncatula/microbiologia , Dados de Sequência Molecular , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Fenótipo , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nodulação , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Sesquiterpenos/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética
3.
Plant Physiol ; 157(4): 2013-22, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22034625

RESUMO

Legumes host their Rhizobium spp. symbiont in novel root organs called nodules. Nodules originate from differentiated root cortical cells that dedifferentiate and subsequently form nodule primordia, a process controlled by cytokinin. A whole-genome duplication has occurred at the root of the legume Papilionoideae subfamily. We hypothesize that gene pairs originating from this duplication event and are conserved in distinct Papilionoideae lineages have evolved symbiotic functions. A phylogenetic strategy was applied to search for such gene pairs to identify novel regulators of nodulation, using the cytokinin phosphorelay pathway as a test case. In this way, two paralogous type-A cytokinin response regulators were identified that are involved in root nodule symbiosis. Response Regulator9 (MtRR9) and MtRR11 in medicago (Medicago truncatula) and an ortholog in lotus (Lotus japonicus) are rapidly induced upon Rhizobium spp. Nod factor signaling. Constitutive expression of MtRR9 results in arrested primordia that have emerged from cortical, endodermal, and pericycle cells. In legumes, lateral root primordia are not exclusively formed from pericycle cells but also require the involvement of the root cortical cell layer. Therefore, the MtRR9-induced foci of cell divisions show a strong resemblance to lateral root primordia, suggesting an ancestral function of MtRR9 in this process. Together, these findings provide a proof of principle for the applied phylogenetic strategy to identify genes with a symbiotic function in legumes.


Assuntos
Genes de Plantas/genética , Genoma de Planta/genética , Medicago truncatula/genética , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Sinorhizobium/fisiologia , Sequência de Bases , Evolução Biológica , Divisão Celular , Citocininas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes Duplicados/genética , Lotus/genética , Lotus/microbiologia , Lotus/fisiologia , Medicago truncatula/citologia , Medicago truncatula/microbiologia , Medicago truncatula/fisiologia , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Nódulos Radiculares de Plantas/genética , Plântula/citologia , Plântula/genética , Plântula/microbiologia , Plântula/fisiologia , Análise de Sequência de DNA , Transdução de Sinais , Glycine max/genética , Glycine max/microbiologia , Glycine max/fisiologia , Simbiose/fisiologia
4.
Curr Opin Plant Biol ; 15(4): 438-43, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22633856

RESUMO

For almost a century now it has been speculated that a transfer of the largely legume-specific symbiosis with nitrogen fixing rhizobium would be profitable in agriculture [1,2]. Up to now such a step has not been achieved, despite intensive research in this era. Novel insights in the underlying signalling networks leading to intracellular accommodation of rhizobium as well as mycorrhizal fungi of the Glomeromycota order show extensive commonalities between both interactions. As mycorrhizae symbiosis can be established basically with most higher plant species it raises questions why is it only in a few taxonomic lineages that the underlying signalling network could be hijacked by rhizobium. Unravelling this will lead to insights that are essential to achieve an old dream.


Assuntos
Fabaceae/metabolismo , Glomeromycota/metabolismo , Micorrizas/metabolismo , Fixação de Nitrogênio/fisiologia , Nitrogênio/metabolismo , Rhizobium/metabolismo , Simbiose/fisiologia , Fabaceae/microbiologia , Lipopolissacarídeos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Transdução de Sinais/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA