Research Article Diallel and prediction (REML/BLUP) for yield components in intervarietal maize hybrids.

Abstract

ABSTRACT. Genetic improvement is essential to achieve increments in maize (Zea mays L.) grain yield components. It may be obtained through crosses, which enable to exploit the effects of intervarietal heterosis, allelic complementarity, as well as gene actions and effects. This study estimated the components of variance and genetic parameters (REML/BLUP) of an intervarietal diallel to select and predict the best genotypes for maize yield components. The experimental design was randomized blocks containing 60 intervarietal maize hybrids arranged in three repetitions. They were obtained through intervarietal crosses and evaluated in a diallel scheme, where 14 open-pollinated varieties were designated as parentals. Thus, 10 crosses were performed for each hybrid combination to obtain the number of seeds necessary for the competition test. The measured traits were: grain volume relative index, the mass of one hundred grains, and grain yield. The male parents and the additive genetic fraction were determinants for grain volume relative index. Mass of one hundred grains and grain yield were defined by the specific combining ability, and female parents revealed low narrow sense heritability. The female parent Taquarão and male parent Argentino Amarelo presented the best general combining abilities for the measured traits. The specific combining abilities were expressed for crosses AL 25 x Dente de Ouro Roxo, AL 25 x BRS Pampeano, and Taquarão x Argentino Branco. Genetic estimates and predictions were consistent and applicable to breeding programs and could be applied in future quantitative genetic studies of maize.

Research Article Genetic parameters prediction (REML/BLUP) for morphological, physical-chemical, phytochemical, and mineral components of primocane-fruiting raspberries

“…The new predicted mean defines that the clones should produce at a rate similar to commercial crops (Borges et al, 2010). If the genotypic predicted estimated value (g + u) is similar to the new mean, this prediction is probably real (Carvalho et al, 2017). In our study, the predicted values were similar to the new mean, which means that these estimates are reliable and consistent.…”

“…However, knowledge of the genetic mechanism that controls the inheritance of a trait and the impact of genetic and environmental factors on their expression is essential for a successful breeding program (Akšić et al, 2011). A good procedure to estimate variance components and predict genetic parameters is through Restricted Maximum Likelihood (REML) and Best Linear Unbiased Prediction (BLUP), respectively (Carvalho et al, 2017).…”

Adaptability, Stability and Multivariate Selection by Mixed Models

“…Currently, breeding programs seek to identify high yielding genotypes, and posteriorly target their selection strategies in the quality of the grains, thus, the search for the ideal genotype that gathers productive and qualitative superiority demands elevated financial and labor resources of the breeding program, as well as suitable selecting strategies [3] [4] [5] [6]. An alternative to minimize this obstacle is the multivariate selection, which aims to select a set of simultaneous traits.…”

Path analysis and canonical variables of intervarietal maize hybrids

“…These results corroborate with Kleinpaul et al (2014), which reveals positive associations between plant height and spike insertion height. The correlation allows comprehending the occurrence of associations between traits (Churata and Ayala-Osuna, 1996;Carvalho et al, 2017). On this way, the trait stem diameter revealed coefficient of correlation intermediate and positive with SL (r=0.30) and NGR (r=0.37) and weak and positive with SGM (r=0.27) and GY (r=0.27).…”