Proposal of a super trait for the optimum selection of popcorn progenies based on path analysis

Abstract

ABSTRACT.A challenge faced by popcorn breeding programs is the existence of a negative correlation between the two main traits, popping expansion and yield, which hinders simultaneous gains. The objective of this study was to investigate the use of a new variable or super trait, which favors the reliable selection of superior progenies. The super trait 'expanded popcorn volume per hectare' was introduced in the evaluation of 200 full-sib families of the eighth recurrent intrapopulation selection cycle, which were arranged in randomized blocks with three replicates in two environments. Although the inability to obtain simultaneous gains through selection via popping expansion or yield was confirmed, the super trait was positively associated with both yield and popping expansion, allowing simultaneous gains via indirect selection using 'expanded popcorn volume per hectare' as the main trait. This approach is recommended because this super trait can be used in breeding programs to optimize selective gains for the crop.

Genomic selection helps accelerate popcorn population breeding

“…do Amaral Júnior et al. (2016) also observed the weaker environmental influence on the expression of PE than on GY. The low heritability (0.43) obtained for PV can be explained by the fact that this trait is a combination of GY and PE and also incorporates the environmental influence in the expression of two polygenic traits.…”

“…A challenge faced by popcorn breeding programs is the existence of a low correlation between the two main traits, PE and GY, which hinders simultaneous gains. Under these circumstances, the super‐trait PV can be used in breeding programs to optimize selective gains for the crop (do Amaral Júnior et al., 2016).…”

Can Genetic Progress for Drought Tolerance in Popcorn Be Achieved by Indirect Selection?

“…Reports in the literature suggest that a larger tassel size and greater number of tassel branches tend to reduce grain yield, due to the reduction in sunlight interception by the flag leaves (self-shading) and competition for photoassimilates by different plant structures [31]. Plant height is frequently positively correlated with grain yield in popcorn [24,41] and maize [17,42]. On the other hand, higher SPAD values reflect an intensified activity of the photosynthetic machinery, particularly under DS [9,36].…”

“…Based on simple correlations, SPAD was considered a reliable trait for selection for DS tolerance in maize [9]. In addition, NGR is a trait frequently associated with higher yields [24]. The use of easily measurable and highly responsive traits can increase the efficiency of selection under stress conditions [35].…”

“…Therefore, the objective of this study was to estimate the effects of direct and indirect influence of agricultural, morphological, physiological and root architecture traits of popcorn genotypes under two water regimes, on the main variable: expanded popcorn volume per hectare (EPV), considered a supertrait, for representing the product of the two main economically important traits of the crop: popping expansion and grain yield [24]. In practice, this research concludes with the indication of secondary characteristics that can be used for the selection of more productive genotypes in dry conditions, that is, more agronomically efficient genotypes in water use [25], favoring the practice of a more sustainable agriculture in the use of water resources.…”