03227naa a2200325 a 450000100080000000500110000800800410001902200140006002400300007410000170010424502170012126000090033830000090034750010790035652011670143565300150260265300150261765300210263265300140265365300210266765300130268865300140270165300160271565300150273170000140274670000160276070000200277670000200279677300850281610616362021-03-11       2020    bl uuuu     u00u1 u    #d  a2301-15487 a10.31285/AGRO.24.3812DOI1 aCASTILLO, A.  aPolyploid induction of Eucalyptus dunnii Maiden to generate waviability in breeding programs. [Polyploid induction of Eucalyptus dunnii Maiden to generate variability in breeding programs].h[electronic resource]  c2020  a9 p.  aArticle history: Received 29 Jun. 2020 // Accepted 28 Sep. 2020 // Published 17 Dec 2020. Comité científico editor: Dra. Marisa López-Bilbao (INTA, Hurlingham, Provincia de Buenos Aires, Argentina); Dra. Sandra Sharry (Universidad Nacional de la Plata, La Plata, Buenos Aires, Argentina); Dra. Alicia Castillo (Investigadora Principal, Unidad de Biotecnología de INIA, Uruguay) ; Dr. Juan Izquierdo (Profesor Libre Facultad de Agronomía, Udelar, Presidente Academia Chilena Ciencias Agronómicas) ; Dr. Gerardo Gallego (Coordinador del Laboratorio de Biotecnología Vegetal del Centro Internacional de Agricultura Tropical-CIAT Cali, Colombia) ; Dra. Elizabeth Hodson (Profesora emérita de la Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia); Dr. Paul Chavarriaga (líder de la plataforma de transformación genética y edición de genomas del Centro Internacional de Agricultura Tropical-CIAT Cali, Colombia) ; Dr. Marco Dalla-Rizza (Coordinador de la Unidad de Biotecnología, Investigador principal referente, presidente REDBIO 2016-2020).  aEucalyptus dunnii Maiden produces good quality cellulose pulp, showing good frost tolerance. However, in Uru-guay, it needs more than six  years to reach the reproductive stage. Genome duplication was proposed as a strategy to obtain useful variability. The application of mitosis inhibitors for chromosomal duplication, in explants growing in vitro, was evaluated. Two antimitotic agents were used: colchicine and oryzalin in different concen-trations and exposure times, in two types of explants: explants growing in vitro and pre-germinated seeds. The number of chloroplasts was used as a rapid ploidy estimator and confirmed by flow cytometry. For chloroplast count,  fluorescein  diacetate  (FDA)  applied  to  in  vitro  leaves  was  used  for  staining.  Oryzalin  was  effective  for  inducing plant duplication in E. dunnii from in vitro explants. In pre-germinated seeds, both antimitotic agents induced polyploids. The average number of chloroplasts was 5.5 in diploid control plants and more than 7 in tetraploids. Obtained plantlets were successfully cloned in the greenhouse. This is the first report on artificial polyploidy obtained in E. dunnii.  aCOLCHICINA  aCOLCHICINE  aCULTIVO IN VITRO  aEUCALIPTO  aIN VITRO CULTURE  aORYZALIN  aORYZALINE  aPOLIPLOIDIA  aPOLYPLOIDY1 aLOPEZ, V.1 aTAVARES, E.1 aSANTIÑAQUE, F.1 aDALLA RIZZA, M.  tAgrociencia Uruguay 2020gv. 24, no. NE2, Article 381. DOI: 10.31285/AGRO.24.413