Phenotypic and genotypic correlations between soybean agronomic traits and path analysis

Abstract

The goals of this research were to evaluate the phenotypic and genotypic correlations between agronomic traits, to perform path analysis, having as main character grain yield, and to identify indirect selection criteria for grain yield. The experiment was carried out in an experimental area located at Capim Branco farm, which belongs to Federal University of Uberlândia, during the growing season of 2015/2016.Twenty-four soybean genotypes were evaluated under randomized complete block design with three repetitions, of which agronomic traits and grain yield were measured. There was genetic variability for all traits at 5% probability level through the F-test. Thirty significant phenotypic correlations were also observed with values oscillating from 0.42 to 0.87, which indicated a high level of association between some evaluated traits. Additionally, we verified that phenotypic and genotypic correlations were essential of the same direction, being the genotypic ones of superior magnitudes. Plants with superior vegetative cycle had longer life cycles; this fact could be explained by the significant phenotypic correlations between the number of days to the blooming and number of days to maturity (0.76). Significantly positive phenotypic and genotypic correlations for the total number of pods per plant and grain yield per plant (0.84) were observed. Through the path analysis, the trait that contributed the most over grain yield was the number of pods with three seeds as it showed the highest direct effect on grain yield per plant, as well as a strong indirect effect on the total number of pods. Therefore, the phenotypic and genotypic correlations suggested high correlations between grain yield and number of branched nodes, the number of pods with two and three seeds, and the total number of pods. Also, the path analysis determined the number of pods with three seeds as having the highest favorable effect on grain yield, and thus, being useful for indirect selection toward productive soybean genotypes.

Correlation and Path Coefficient Analysis for Seed Yield and some of its Traits in ‎Common Bean (Phaseolus vulgaris L.)‎

“…The correlation coefficient is useful for measuring the degree and direction of association between traits. However, it can generate deceptive results because the high degree of correlation between two traits may happen due to the indirect effect of a third one (Cruz et al, 2012) (as cited in Machado et al, 2017). Consequently, it is necessary to examine the cause and effect relationship between variables.…”

Genetic correlation and path analysis of agronomical traits of soybean (Glycine max) lines infected by CpMMV

“…number of reproductive nodes and number of branches, had a significant phenotypic and genotypic correlation to the seed yield respectively (Table 1). Machado et al (2017) also reported that number of branches had significant genotypic and phenotypic correlation to seed yield. These two characters had a important role in the increase of seed yield per plant.…”

“…Genetic correlation involves a relationship of heritable nature that allows heritable selection between the traits. Therefore, the study of genetic correlation is crucial to identifying the traits that can be used as an indirect selection for grain yield (Machado et al 2017).…”

Agronomic evaluation and web blight resilience of common bean genotypes in the littoral region of Ecuador

“…All these differences might be explained by a genetic basis. The authors have demonstrated, that a high correlation between phenotypic and genotypic variability (Machado et al, 2017) exists. Ultimately, the relative regularity of the genotypes in the plane allows us to accept that for this experiment, we used an important and representative sample amount of the available genetic resources of common beans in Ecuador, and the others introduced from Colombia.…”