Factor analysis and SREG GGE biplot for the genotype × environment interaction stratification in maize

Abstract

ABSTRACT

Combining ability of tropical maize cultivars in organic and conventional production systems

“…The results of this study were similar to those of MURPHY et al (2007), who evaluated 35 lines of winter wheat in organic and conventional systems at five locations over two years and found significant differences in performance for the genotypes x production systems interaction at four of the five sites. The different response of maize genotypes in different environments is common and the genotype x environments interaction is very important for plant breeding (MIRANDA et al, 2009;FALUBA et al, 2010;FRITSCHE-NETO et al, 2010b). Differences in cultivar performance between organic and conventional environments were found by SILVA et al (2007) for maize and by PRZYSTALSKI et al (2008) for barley, wheat and winter triticale, from trials performed in Denmark, Sweden, Netherlands, France, Switzerland, UK and Germany.…”

Factor analysis applied to the G+GE matrix via REML/BLUP for multi-environment data

“…A commonly adopted criterion is to retain the factors whose eigenvalues are greater than or equal to 1.0 (Kaiser-Guttman criterion); or, if the explanatory proportion of these factors is low, a set of factors should be used which explain up to 80% of the total variation , Mendonça et al 2007, Fritsche-Neto et al 2010b, Ribeiro and Almeida 2011). In this study, 80% of the variation is achieved from six factors, which is fewer than the number of factors indicated by the eigenvalues greater than 1.0 (seven).…”

Análises Biplot: conceitos, interpretações e aplicações

“…Como, em geral, o PC1 está correlacionado com o efeito do genótipo, é possível alta precisão na visualização gráfica do escore PC1 quanto ao efeito genotípico. YAN et al (2000) acreditam que esta proporcionalidade da resposta de genótipos seja mais lógica e biologicamente plausível, pois há correlação quase perfeita entre o rendimento de grãos e o PC1 (NETO-FRITSCHE et al, 2010;SINEBO et al, 2010). Por outro lado, no modelo AMMI2, tem-se observado correlação negativa entre IPC1 e o rendimento (KVITSCHAL et al, 2009).…”