Genetic effects on the efficiency and responsiveness to phosphorus use in popcorn as estimated by diallel analysis

Abstract

Agricultural expansion and the need for sustainable cultivation are challenges faced by researchers involved in the generation of new cultivars that can adapt to abiotic stress. Knowledge of the genetic effects of characteristics related to efficiency and responsiveness to phosphorus use must be considered when implementing methods to obtain better genotypes. The aim of this study was to characterize and select popcorn hybrids based on their efficiency and responsiveness to phosphorus use, and estimate their combining abilities and genetic effects via diallel analysis to implement improvement programs for sustainable agriculture. Eight contrasting inbred lines were used to obtain simple hybrids for diallel analysis. Twenty-eight diallelic hybrids plus the popcorn parental lines were evaluated at two different sites under two contrasting environments for soil phosphorus availability (6 × 6 lattice design). Grain yield, popping expansion, and volume of expanded popcorn per hectare were measured. A combined analysis of variance and a test of means were performed. The classification and utilization of the phosphorus use efficiency index, according to the grain yield performance of the hybrids under contrasting environments, was considered. Through model 2 of the Griffing’s diallel analysis method, the general and specific combining abilities were estimated, along with their environmental interactions. The best strategy to obtain genotypes that are efficient and responsive to phosphorus involves exploring popcorn hybrids using genitors that result in the accumulation of additive genes that promote popping expansion. Hybrids P7 × L80, P7 × L59, P7 × L76, and P6 × L80 presented promising results and may be evaluated as cultivation options in phosphorus-deficient soils.

Driving Sustainable Popcorn Breeding for Drought Tolerance in Brazil

“…Regarding PE, the estimates of GCA effects on the P7 and L61 inbred lines showed that they were the most promising candidates, as the effects revealed the highest positive magnitudes of g i in both CSs and WCs. As PE is negatively correlated with GY, inbred lines with high GCA values for PE and low CGC values for GY or vice versa are commonly obtained (Cabral et al, 2016;de Lima et al, 2016;Mafra et al, 2018;Gerhardt et al, 2019) as we observed for L61. However, P7 had high values for both traits, which makes it of great importance for breeding programs when simultaneously exploring the potential for GY and PE.…”

“…For maize under drought conditions, both non-additive (Derera et al, 2008 ; Adebayo et al, 2014 ) and additive effects were observed (Chapman and Edmeades, 1999 ; Betrán et al, 2003 ; Dhliwayo et al, 2009 ). The prevalence of the dominance effects for GY and additive effects for PE was observed in popcorn under soil nitrogen (N)-limited conditions (Santos et al, 2019 , 2020 ) and phosphorus (P)-limited conditions (Gerhardt et al, 2019 ). When evaluating popcorn genotypes under water-deficit conditions, Lima et al ( 2019 ) verified that dominance effects prevailed for GY while the same was true for additive effects for PE.…”

“…Genetic effects controlling popcorn traits under well-watered conditions (Larish and Brewbaker, 1999 ; Pereira and Amaral Júnior, 2001 ; Silva et al, 2010 ; Jele et al, 2014 ; Dar et al, 2018 ; Coan et al, 2019 ; Schwantes et al, 2020 ), biotic stresses (Schwantes et al, 2017 ; Mafra et al, 2018 ; Amaral Júnior et al, 2019 ; Kurosawa et al, 2020 , 2021 ), and nutritional deficiencies (Gerhardt et al, 2019 ; Santos et al, 2019 , 2020 ) have revealed that the additive genetic action is prevalent for PE, whereas the non-additive action has been the most important for GY expression and its components. In addition, non-additive genetic effects were the most prevalent controlling GY under water limitations in tropical maize (Betrán et al, 2003 ).…”

Understanding the combining ability for physiological traits in soybean

“…Diallel crosses provide information about the genetic control of the traits evaluated, which helps in conducting and selecting segregating populations [6, 7]. The diallel also allows the breeder to know the per se behavior of the parents, called general combining ability (GCA), besides their hybrid combinations, called specific combining ability (SCA).…”

Genetic behavior analysis for phytochemical traits in coriander: Heterosis, inbreeding depression and genetic effects

“…Griffing’s (1956) diallel analysis has used to uncover the behavior of genes involved in controlling of the traits. This method has also used to estimate variance of GCA and SCA in different self-pollinated and open-pollinated crops (Khan et al, 2009; Blank et al, 2012; Townsend et al, 2013; El-Gabry et al, 2014; Khodadadi et al, 2016b; Khodadadi et al, 2017; Kaushik et al, 2018; Teodoro et al, 2019; Schegoscheski Gerhardt et al, 2019).…”