Heterosis and combining ability in crosses between two groups of open-pollinated maize populations

Abstract

-The rapid expansion of corn in Brazil indicates

Inbreeding depression and genetic variability in agricultural traits and resistance to phytopathogens in exotic maize populations

“…However, its use in maize breeding programs around the world has been inexpressive (GOODMAN, 2005). The potential of exotic or semi-exotic populations in maize breeding programs has been reported by several authors MENDES et al, 2015;SILVA et al, 2017;SOUZA et al, 2018). Juliatti et al 2004Juliatti et al , 2009 and 2013 showed the possibilities of selection to plant pathogens resistance at endogamic population in maize to main diseases (cercospora leaf spot, common rust and white spot).…”

Genetic Enhancement of Semi-Exotic Maize Germplasm

“…Revista Brasileira de Milho e Sorgo, v.15, n.2, p. 346-356, 2016 Versão impressa ISSN 1676-689X / Versão on line ISSN 1980-6477 -http://rbms.cnpms.embrapa.br recombination of late accesses after crossing with the hybrid P-3041 (Basso & Miranda Filho, 2001). , 06, 07, 08, 09, 11, 14, 15, 16, 19, 25 21, 22 and 23 were also studied by Mendes et al (2015) in crosses with six local and adapted synthetics symbolized by HG; from the 24 hybrid crosses in this set, the number that yielded more than 80% of the hybrid check was 9 in Jatai (GO) and 7 in Rio Verde (GO). Also, a high expression of heterosis for yield was observed in that crosses, varying from 18.8% to 46.5% in Jatai and from 10.7% to 55.4% in Rio…”

“…TUTU 17 (Goodman & Brown, 1988;Goodman, 2005) included germplasm from diverse origins (Miranda Filho et al, 2000). Populations numbered as 20, 21, 22 and 23 were also studied by Mendes et al (2015) in crosses with six local and adapted synthetics symbolized by HG; from the 24 hybrid crosses in this set, the number that yielded more than 80% of the hybrid check was 9 in Jatai (GO) and 7 in Rio Verde (GO). Also, a high expression of heterosis for yield was observed in that crosses, varying from 18.8% to 46.5% in Jatai and from 10.7% to 55.4%…”

“…In fact, the evaluation of exotic and semiexotic populations have shown the importance of their use in breeding programs. Mendes et al (2015) worked in a project for the incorporation of semiexotic germplasm into local and adapted populations and showed good perspectives for the enhancement of the basic germaplasm for the conditions of the Southwest region in the State of Goiás. In the same line, Oliveira et al (2015aOliveira et al ( , 2015b reported on the performance of three semiexotic populations derived from exotic germplasm with potential for corn stunt resistance and concluded that the program was based on appropriate strategies for widening the perspectives of breeding programs.…”

Identification of heterotic patterns between expired proprietary, NDSU, and industry short-season maize inbred lines

“…Heterotic groups represent groups of germplasm sources that when crossed with each other produce consistently better crosses than when crosses are made within those groups (Hallauer and Carena 2009). Identifying heterotic patterns, which are crosses between known genotypes (from different heterotic groups) expressing a high level of heterosis (Carena and Hallauer 2001, Troyer 2006, Mendes et al 2015, is key to the development of successful maize hybrids (Eyherabide and Hallauer 1991, Barata and Carena 2006, Carena and Wicks III 2006. The North American dent maize germplasm is composed of multiple heterotic groups that when crossed to each other can optimize hybrid performance (Mikel and Dubley 2006).…”