Germplasm of maize: enhancement of genetic values

• Grant number: 11/17307-6
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2012
• End date: August 31, 2014
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Jose Branco de Miranda Filho
• Grantee: Jose Branco de Miranda Filho
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated researchers: Antonio Augusto Franco Garcia

Abstract

In the present project, three research lines related to the introgression of exotic germplasm will be considered. All the populations taken as basic material belong to the Department of Genetics (ESALQ/USP). [I]: Twelve semi-exotic populations will be evaluated in crosses with two local testers following the partial diallel scheme (12 x 2), including the 14 parental populations, 24 F1 crosses and 24 F2 crosses; the experimental trials will be as completely randomized blocks with split-plots. The final results will give information on the genetic properties of the semi-exotic populations and guide for the appropriate proportion of local germplasm to be incorporated toward the enhancement of their genetic value. [II]: Four semi-exotic populations with high expression for earliness will be submitted to intrapopulation recurrent selection based on topcross of S1 lines as selection unities followed by recombination of the selected S1 lines. For each population, samples will be represented by 150 evaluated and 15 selected progenies. Besides the direct effect of selection, results will also provide information on the genetic structure and on the potential of variability and productivity of the base populations. [III]: Fifty S1 lines from each semi-exotic populations (already cited in II) will be used to generate 50 pairs of S2 lines, from which 25 pairs will be chosen to be crossed according to the partial circulant diallel scheme (intrapopulation). Results will be useful to infer on the genetic value of the base populations for the development of inbred lines and on the effectiveness of the methodology used for evaluation of inbred lines and hybrids. (AU)