Alterations in heterosis of maize populations derived from single-cross hybrids after reciprocal recurrent selection

Abstract

One hundred and sixty-nine interpopulational half sib progenies were obtained from maize populations derived from the commercial single-cross hybrids AG9012 (1) and C333 (2) to investigate the efficiency of reciprocal recurrent selection (RRS). Fifteen progenies with highest hulled ear yield were obtained. Two recombination trials were sown with remnant S 1 seeds, and the improved CI 1 and CI 2 populations were simultaneously obtained with their hybrid combination. Yield trials were set up in three sites to assess the efficiency of the RRS. The F 1 from single-cross hybrid AG9012 and C333, the doublecross (F 1(1) x F 1( 2) ) hybrids, the C0 1 and C0 2 populations, the interpopulational hybrid (C0 1 x C0 2 ), the CI 1 and CI 2 improved populations, and their hybrid (CI 1 x CI 2 ) were compared. A 5.7% progress was obtained in one cycle of RRS for ear yield, mainly attributed to increased heterosis. The yield of the improved hybrid was superior to the F 1 from single-cross hybrids AG9012 and C333, demonstrating the potential of the referred hybrid combination.

Progresso genético com a seleção recorrente recíproca para híbridos interpopulacionais de milho

“…2009 observa-se coerência com os relatos de SRR presentes na literatura. Trabalhos com populações derivadas de híbridos simples mostraram respostas de 5,7 (Raposo et al, 2004), 4,5 e 6,2% (Coors, 1999) à seleção por ciclo. Em programas com populações temperadas (BS10 e BS11) submetidas à SRR de irmãos germanos por oito ciclos, Eyherabide & Hallauer (1991) reportaram ganho de 6,5% por ciclo.…”

“…bras., Brasília, v.44, n.12, p.1667-1672, dez. 2009 A SRR com uso de populações derivadas de híbridos simples já se mostrou viável em outras condições (Coors, 1999;Raposo et al, 2004). No entanto, é necessário utilizar um método de SRR que seja mais dinâmico e rápido.…”

Genetic Progress in 20 Years of Reciprocal Recurrent Selection in Maize

“…Similarly, Russell et al (1992) obtained 4.9% in the interpopulation hybrid from the cross between BS21 (R) x BS22 (R) populations during three selection cycles. Raposo et al (2004) and Reis (2013) reported 5.7 and 4.5% increases in grain yield, respectively, after three RRS cycles, in populations from simple hybrids.…”

“…It can be seen that CIMMYT populations (Figure 3a) presented lower performance than other genotype groups and production instability along the cycles. A number of authors report that, when it comes to reciprocal recurrent selection, it is common to obtain little or no gain in one of the populations (Keeratinijakal and Lamkey, 1993;Raposo and Ramalho, 2004;Hallauer Carena, 2009;Reis et al, 2013). For the CIMMYT populations, it was verified an increase of 44 kg.ha -1 .cycle -1 of selection and 22 kg.ha -1 .year -1 , of which values are not significant by the t test at 1% probability and an R² of 0.08 (Figure 3).…”