title: Verification and characterization of chromosome duplication in haploid maize.
abstract: Doubled haploid technology has been used by various private companies. However, information regarding chromosome duplication methodologies, particularly those concerning techniques used to identify duplication in cells, is limited. Thus, we analyzed and characterized artificially doubled haploids using microsatellites molecular markers, pollen viability, and flow cytometry techniques. Evaluated material was obtained using two different chromosome duplication protocols in maize seeds considered haploids, resulting from the cross between the haploid inducer line KEMS and 4 hybrids (GNS 3225, GNS 3032, GNS 3264, and DKB 393). Fourteen days after duplication, plant samples were collected and assessed by flow cytometry. Further, the plants were transplanted to a field, and samples were collected for DNA analyses using microsatellite markers. The tassels were collected during anthesis for pollen viability analyses. Haploid, diploid, and mixoploid individuals were detected using flow cytometry, demonstrating that this technique was efficient for identifying doubled haploids. The microsatellites markers were also efficient for confirming the ploidies preselected by flow cytometry and for identifying homozygous individuals. Pollen viability showed a significant difference between the evaluated ploidies when the Alexander and propionic-carmin stains were used. The viability rates between the plodies analyzed show potential for fertilization.
authors.affiliation: Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil evellyn.couto@yahoo.com.br.
authors.forename: E G
authors.initials: EG
authors.lastname: de Oliveira Couto
authors.affiliation: Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil.
authors.forename: E V
authors.initials: EV
authors.lastname: Resende Von Pinho
authors.affiliation: Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil.
authors.forename: R G
authors.initials: RG
authors.lastname: Von Pinho
authors.affiliation: Embrapa Cerrados, Planaltina, DF, Brasil.
authors.forename: A D
authors.initials: AD
authors.lastname: Veiga
authors.affiliation: Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil.
authors.forename: M R
authors.initials: MR
authors.lastname: de Carvalho
authors.affiliation: Departamentode Biologia, Universidade Federal de Lavras, Lavras, MG, Brasil.
authors.forename: F
authors.initials: F
authors.lastname: de Oliveira Bustamante
authors.affiliation: Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil.
authors.forename: M S
authors.initials: MS
authors.lastname: Nascimento
mesh_terms: D002470:Cell Survival; D002678:Chimera; D058674:Chromosome Duplication; D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D018744:DNA, Plant / Q000032:analysis / Q000235:genetics*; D005434:Flow Cytometry; D006720:Homozygote; D018895:Microsatellite Repeats; D011003:Ploidies; D011058:Pollen / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D012639:Seeds / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure; D013194:Staining and Labeling; D003313:Zea mays / Q000235:genetics* / Q000254:growth & development / Q000648:ultrastructure
chemical_list: D018744:DNA, Plant