Occurrence of 2 n microspore production in diploid interspecific hybrids between the wild parental species of peanut ( Arachis hypogaea L., Leguminosae) and its relevance in the genetic origin of the cultigen

Unreduced (2n) gametes are the driving force that leads to polyploidization of plants in nature and an important tool for ploidy breeding. Peanut (Arachis hypogaea L., Leguminosae) seems most likely to have originated by sexual polyploidization through interspecific hybridization between the wild di...

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Detalles Bibliográficos
Autores: García, Alejandra Vanina, Ortiz, Alejandra Marcela, Silvestri, María Celeste, Custódio Alves, Raquel, Moretzsohn, M. C., Lavia, Graciela Inés
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/108563
Acceso en línea:http://hdl.handle.net/11336/108563
Access Level:acceso embargado
Palabra clave:PEANUT
GENETIC ORIGIN
SEXUAL POLIPLOIDIZATION
UNREDUCE GAMETES
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:Unreduced (2n) gametes are the driving force that leads to polyploidization of plants in nature and an important tool for ploidy breeding. Peanut (Arachis hypogaea L., Leguminosae) seems most likely to have originated by sexual polyploidization through interspecific hybridization between the wild diploid relatives -A. duranensis and A. ipaënsis-, and subsequent binding of the unreduced gametes in the hybrid. Therefore, aiming to contribute to the understanding the event of polyploid origin of this important crop, we made diploid hybrids between A. duranensis and A. ipaënsis, and then investigated the production of unreduced gametes in the hybrids by analyzing the size range of pollen, the constitution of the sporads, and the microsporogenesis process. The meiotic abnormalities found, such as persistent bridges, tripolar spindles and cytomixis processes, would lead to the formation of restitution nuclei in both the first and second meiotic division. These failures in the regularityof meiosis lead to the formation of dyads and triads, and consequently to 2n pollen grains. These findings constitute the first evidence of the formation of unreduced gametes in intergenomic hybrids obtained between the wild progenitors of A. hypogaea and enable us to propose a model of origin of the crop through sexual polyploidization.