Data/hora: 21/06/2024 04:08:43

Biblioteca(s): 	Embrapa Café.	
Data corrente: 	27/03/2023	
Data da última atualização: 	12/04/2023	
Autoria: 	ANGELO, P. C. da S.; PEREIRA, L. F. P.; SERA, G. H.; SETA, T.	
Afiliação: 	PAULA CRISTINA DA SILVA ANGELO, CNPCa; L. F. P. PEREIRA, IDR - PARANÁ; G. H. SERA, IDR - PARANÁ; T. SERA, IDR - PARANÁ.	
Título: 	Coffee microspore cultivation to attain doubled-haploid plantlets.	
Ano de publicação: 	2023	
Fonte/Imprenta: 	Acta Horticulturae, v. 31, n. 1359, p. 123-130, 2023.	
DOI: 	10.17660/ActaHortic.2023.1359.14	
Idioma: 	Inglês	
Notas: 	Apresentado no INTERNATIONAL HORTICULTURAL CONGRESS, 31., 2022, Angers, França.	
Conteúdo: 	Introgression of disease resistance from related Coffea species to C. arabica has been done by inter-specific hybridization. C. arabica (tetraploid) × C. racemosa (diploid) hybrids were obtained at the IDR-Paraná, Brazil. Some of the hybrids display impaired self-pollination, despite backcrossed to C. arabica. As an attempt to regenerate stable doubled-haploid plants, anthers and isolated microspores have been cultivated in vitro. It was considered that chromosomes captured in a microspore following meiosis could acquire homo and/or homeologous stability faster in vitro than in vivo. A C. arabica progeny was taken as control. Flowers were collected at the IDR campus in Londrina, when young microspores were uninucleate, and treated with 8% active chlorine. Microspores were extracted in 90 mM mannitol using a food mixer set to function for a few seconds, washed and centrifuged at 100× g twice, and cultivated in modified N6 liquid medium (105 cells mL-1 in 35 mm diameter plates). Anthers were excised using scalpels and cultivated in solid medium. Explants were kept for six months of continuous cultivation on that induction medium containing 6.5 mg L-1 auxins, 1.0 mg L-1 cytokinins and 0.5 mg L-1 gibberellin (GA3), at 27°C under dark. Microspores produced embryo-like structures or microcalli in very low frequencies (0.3 per plate). Anthers, on the other hand, produced embryogenic calli. Colonization by an invariant morphotype of fungus took away 70% of Arabica coffee control anthers and 5% of the asseptic anthers produced friable calli, some embryogenic but arrested when compared with calli produced by the inter-specific hybrid anthers. Colonization by an invariant morphotype of bacteria took away 25% of hybrid anthers and 8% of produced embryogenic tissue, with globular embryos simultaneously multiplying and maturing upon transfer to N6 medium. Embryo conversion and photomorphogenesis under light on auxin/cytokinin ratio = 2 plus GA3 are going on, 1.2 year after inoculation.	
Thesagro: 	Embriogénese; Pólen; Rubiaceae.	
Thesaurus Nal: 	Embryogenesis; Pollen.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Café (CNPCa)	
Exemplares: 	CNPCa - (1692-1) - UPC - AP - DD -  -  -  - DIS