Gene Action for Several Important Traits in Some Promising Maize -Teosinte Hybrids Using Generation Mean Analysis

Abstract

Although the need for increased production of summer fodder is so keenly felt in Egypt, the plant breeders did not focused much of their attention to improv fodder teosinte as silage exchange for maize. In this study, an attempt was made in order to partition the genetic variance to its components for fodder traits through the evaluation of different generations (P1, P2, F1, F2, BC1, BC2) of the promising maize-teosinte crosses under two locations (El-Serw and Sids). The results indicated the presence of significant differences among crosses for all studied traits. Also, the results revealed the presence of significance of populations within crosses and each cross. The cross SC10 × Rayana ( R) was the highest among studied crosses for number of leaves (NL/P) (69.79), number of tillers (NT/P) (6.25), 5 th leaf area (5 th LA) (643.56 cm 2 ) green fodder yield per plant (GFY/p) (3740.0 g) and dry fodder yield per plant (DFY/p) (1191.13 g). While the cross SC 122 × R was the highest for crude protein (CP) (16.52 %), digestible protein (DP) (11.78 %) and total digestible nutrients (TDN) (67.25 %). The F 2 generation of the three crosses in the two locations and their combined were less than corresponding values of F 1 hybrids for all studied traits. This finding reflected the presence of non-additive genetic variance plays the major role in the inheritance of these traits. The results also revealed that, the backcross mean of most of studied crosses tended toward the respective recurrent parent, suggesting the role of additive and dominance gene action effects. Most of studied traits were significantly influenced by one or more type of epistatic effects, which included additive x additive ( aa ), additive x dominance ( ad) and dominance x dominance (dd ) gene action as appeared in the three studied crosses. In general, green fodder yield per plant (GFY/p) was positively with all other traits. Therefore, it wauld be concluded that the production of maize-teosinte hybrids is needed to be used as silage exchange for maize.

Heterosis, Combining Ability and Gene Action, for Yield and Yield Component Traits in Maize-Teosinte Hybrids

“…The hybrid P2 x P3 was the highest mean value for crude fibers (41.99%). These results are in agreement with those obtained by Abdel-Aty et al, (2013), Ghazy (2016) and Sakr (2017).…”

“…These results indicated that non-additive genetic effects played a major role in the genetic expression of this trait, indicating that the hybridization program would be effective in improvement of this trait. Similar results were also found by Sakr (2017) .For the crude fiber %, carbohydrates and crude lipid% the additive genetic variance (σ 2 A) was higher than that non-additive genetic variance (σ 2 D).…”

“…The mean squares of males were highly significant for all traits except crude protein and total digestible nutrients and the mean squares of F x M interaction were highly significant for crude protein and total digestible nutrients. Several researchers found that significant difference for all studied traits not only between parents, but also between their F1 hybrids among those researchers Sakr (2009), Ghazy (2016) and Sakr (2017) in some Maize-Teosinte hybrid.…”

“…Several researchers found significant difference between parents and their F1 hybrids all studied traits, among those researchers Ghazy (2016) and Sakr (2017) in Maize-Teosinte hybrid and Singh et al, (2020) in Maize.…”

Genetic variations in some Egyptian Zea mexicana genotypes based on RAPD and AFLP markers

“…Teosinte has the advantage of giving very high yields, due to profuse tillering capacity that is absent in fodder maize. In addition to the ability to give three cuts against one cut obtained from fodder maize (Sakr, 2017). In addition, maize-teosinte crosses like maize can be safely fed on at any stage of growth (Hassan et al, 2017).…”