Obtenção de linhagen duplo-haplóides de milho

Abstract

The production of double-haploids (DH) being used by maize companies due to the possibility of reducing time and cost spent in obtaining inbred lines. The implementation of routine production of double haploids lines in maize breeding programs in Brazil depends on the establishment of efficient protocols. This work was conducted with two objectives: 1) evaluate the efficiency of obtaining double-haploid lines in maize using two inductors and five methods of chromosome doubling; 2) identify SSR markers to assist phenotypic selection of haploid plants or DH. To this end, was evaluated the efficiency in induction of haploids using hybrid of maize breeding program of Coodetec and the inductors of haploidy Stock 6 and KHI, thereby obtaining seeds/plants genotyping haploids. To the chromosome duplication was used five methods, and colchicine used as antimitotic agent. The identification of haploids or DH was performed by phenotypic analysis and the use of microsatellite molecular markers (SSR). The inductor of haploidy KHI presented the best performance in the induction of genotyping haploids of maize. The methods of chromosome duplication had low efficiency, requiring thus of optimizing protocols. The used of microsatellite molecular markers shown to be efficient to identify the haploids plants or DH, supporting phenotypic selection.