Open Agriculture. 2018; 3: 25–31 Keywords: Gene effects; Heritability; Heterosis; Generation means analysis 1 Introduction Triticale (x Triticosecale Wittmack) in Argentina is potentially suitable to various uses, although the most frequent is direct grazing, it can also be used as a dual purpose and to supplement or include in rations. Triticale is in a free expansion period, especially in sub-humid and semi-arid areas where it successfully replaces the use of rye (Grassi et al. 2004). Its rusticity is similar to rye but with superior forage quality (Amigone and Kloster 1997). The selection of experimental line for grain yield registers varied antecedents in Argentina (Grassi et al. 2003, 2004; Cardozo et al. 2005; Castro et al. 2011; Ferreira et al. 2015). Grain yield is a complex trait with multiple components and is strongly influenced by the environment, in which numerous morphological and physiological traits contribute in its expression. It would be necessary to know the inheritable and not inherited contribution with the help of genetic parameters (Singh and Chaudary 1985; Kahrizi et al. 2010; Maniee et al. 2009). The analysis of the nature and magnitude of the gene effects on quantitative traits helps the researcher to design an efficient improvement program and to provide information on the potential manifestation of heterosis (Shekhawat et al. 2000). Analysis of relative mid-parent heterosis (Mh%) and heterobeltiosis (Hh%) allows to define the breeding strategy (Yildirim et al. 2014). Recent studies in triticale suggest that hybrids performance are significantly higher than cultivated varieties (Oettler et al. 2003; 2005; Yildirim et al. 2014). Generation mean analysis is a simple technique to estimate the genetic effects and to elucidate the nature of the epistasis, being useful to decide the procedure to be adopted in the improvement of quantitative traits (Abd El-Rahman and Hammad 2009). Joint-scaling test https://doi.org/10.1515/opag-2018-0003 received October 9, 2017; accepted December 14, 2017 Abstract: Triticale (x Triticosecale Wittmack) is a cereal used in Argentina as a winter seasonal pasture or feeding grain. Efforts made on breeding have led to varieties with potential grain yield similar or greater than with wheat. The aim of this study was to determine the gene effects, heritability, genetic gain, heterosis and inbreeding depression in various quantitative traits of a cross from contrasting lines of triticale using generation means analysis. The thousand kernel weight was adjusted to a model of additive-dominance, while the rest of the traits exhibited significant epistatic effects: additive x additive (i) for hectoliter weight, additive x dominance (j) for number grains per spike and grain yield per plant. Other traits showed a more complex as inheritance additive x additive (i) and additive x dominance (j) interactions effects for spike length or additive x dominance (j) and dominance x dominance (l) interactions effects for number of spikes per plant and number of spikelets per spike. High values of heritability and genetic gain were also detected for grain yield, spikelets per spike, spike per plant and hectoliter weight. All traits except spike per plant had positive relative mid-parent heterosis, but none resulted in positive heterobeltiosis, therefore this cross is not recommended for obtaining hybrids varieties. Selection in early generations by thousand kernel weight and hectoliter weight would be efficient, while the selection in advanced generations where segregation is minimal would be recommended for the remaining traits. Research Article Enzo David Ferrari*, Víctor Aníbal Ferreira, Ezequiel Martín Grassi, Aurora María Teresita Picca, Héctor Antonio Paccapelo Genetic parameters estimation in quantitative traits of a cross of triticale (x Triticosecale W.) *Corresponding author: Enzo David Ferrari, Faculty of Agronomy, National University of La Pampa, Santa Rosa, La Pampa, Argentina, E-mail: ferrarienzo@agro.unlpam.edu.ar Aurora María Teresita Picca, Héctor Antonio Paccapelo, Faculty of Agronomy, National University of La Pampa, Santa Rosa, La Pampa, Argentina Víctor Aníbal Ferreira, Ezequiel Martín Grassi, Faculty of Agronomy and Veterinary, National University of Río Cuarto, Río Cuarto, Córdo- ba, Argentina Open Access. © 2018 Enzo David Ferrari et al., published by De Gruyter Open. This work is licensed under the Creative Commons Attribution- NonCommercial-NoDerivs 4.0 License. Brought to you by | Universidad Nacional de Rio Cuarto Authenticated Download Date | 2/7/18 3:51 PM