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The objective of this study was to select soybean genotypes derived from crosses between conventional and transgenic lines Roundup Ready (RR), using jointly Restricted Maximum Likelihood/Best Linear Unbiased Prediction (REML/BLUP) approaches, factors analysis and principal components analysis, processed with favorable agronomic traits, during the 2013/2014 growing season. Three agronomic selection processes were identified to select genotypes that discriminate genotypes containing more specific properties. Process 1 (insertion height of first pod, HFP; number of branches, NB; number of pods, NP; number of nodes, NN; and grain yield, GY) was efficient to select earlier, smaller genotypes with good yield/production components and lodging resistance. The junction between mixed model via REML/BLUP and the applied multivariate statistic using factor analysis helped to select suitable genotypes with high performance to carry on the soybean plant-breeding program.

Path analysis is an important study that slices the correlation coefficients between two variables to evaluate whether the relationship between them is of cause and effect. This study aimed to estimate the phenotypic and genotypic correlations between agronomic traits and perform a path analysis in order to identify variables for indirect selection aiming at a higher grain yield. Fourteen soybean F6 lines from the soybean breeding program of FCAV–UNESP, Jaboticabal, São Paulo, Brazil, were analyzed. The experimental design was a randomized block design with three replications. The agronomic traits plant height at maturity (PHM), first pod height (FPH), lodging (Ld), agronomic value (AV), number of pods per plant (NP), number of seeds per plant (NS), and grain yield (GY) were evaluated. Overall, the genotypic correlations were higher than their corresponding phenotypic correlations. The genotypic correlations between grain yield and the traits agronomic value, number of pods per plant, and number of seeds per plant were positive, significant, and of high magnitude. Path analysis showed that the trait number of seeds per plant had the highest direct effect on grain yield, while the trait number of pods per plant had the highest indirect effect through the number of seeds per plant on grain yield

The objective of this work was to compare the Bayesian approach and the frequentist methods to estimate means and genetic parameters in soybean multienvironment trials. Fifty-one soybean lines and four controls were evaluated in a randomized complete block design, in six environments, with three replicates, and soybean grain yield was determined. The half-normal prior and uniform distributions were used in combination with parameters obtained from data of 18 genotypes collected in previous and related experiments. The genotypic values of the genotypes of high- and low-grain yield, clustered by the Bayesian approach, differed from the means obtained by the frequentist inference. Soybean assessed through the Bayesian approach showed genetic parameter values of the mixed model (REML/Blup) close to those of the following variables: mean heritability (h2mg), accuracy of genotype selection (Acgen), coefficient of genetic variation (CVgi%), and coefficient of environmental variation (CVe%). Therefore, the mixed model methodology and the Bayesian approach lead to similar results for genetic parameters in multienvironment trials.

This work evaluated the behavior of coriander half-sib progenies (Coriandrum sativum L.) regarding their agronomic traits. The study was developed in a greenhouse in the Universidade Federal Rural de Pernambuco, PE, Brazil. The experiment was designed as augmented block design with 26 coriander genotypes, of which 24 were coriander half-sib treatments, and two control treatments, 'Verdão' and 'Tabocas'. These progenies were selected from four cycles of phenotypic recurrent selection from the 'Verdão' population, which were selected for later bolting. Plant height and canopy diameter were evaluated in the field, and shoot fresh mass. There were significant differences between the treatment means for all variables analyzed. Regarding analysis of variance and SNK test, there is available variability to select half-sib progenies. Genotypes C 4 -014, C 4 -015, C 4 -016, and C 4 -018 had promising productivity compared to the commercial control varieties. The broad-sense heritability values were 77.3, 81.5 and 95.8% for canopy diameter, shoot fresh mass, and plant height, respectively. This result showed that the majority of phenotypic variance is genetic. Therefore, these genotypes may be used in coriander breeding programs of recurrent selection to obtain cultivars adapted to tropical conditions.