Implications of removing parameters from a mathematical model on relationships among traits in assays with...

The objetive assess the implications of removing parameter effects from a mathematical model on linear relationships in trials with growth-promoting bacteria in soybean crops. The design used consisted of randomized blocks, with four replications. First factor: i) Bradyrhizobium spp. + Azospirillum spp.; ii) Bradyrhizobium spp. + Pseudomonas fluorescens; ii) Bradyrhizobium spp. + Bacillus subtilis; iv) Bradyrhizobium spp. + Bacillus subtilis + Bacillus megaterium; v) Bradyrhizobium spp. + Azospirillum spp. + Pseudomonas fluorescens; vi) Bradyrhizobium spp. + Azospirillum spp. + Bacillus subtilis; vii) Bradyrhizobium spp. + Azospirillum spp. + Bacillus subtilis + Bacillus megaterium; viii) Bradyrhizobium spp. + Azospirillum spp. + Pseudomonas fluorescens + Bacillus subtilis + Bacillus megaterium; ix) no bacteria; and doses of phosphorus: 0, 50, 100 and 150 Kg ha-1. Parameters were removed and compared to the general model in the path and canonical correlation analyses. In the path analysis, there was a change in magnitude from 7.69% to 61.64%, and from 23.08% to 69.23%, concerning the direction of the direct effects. As for indirect effects, magnitude changed from 30.13% to 51.28%, and 33.97% to 55.77%, concerning the direction of the coefficients. In the canonical correlations, the explanatory power increased by up to 338.89% and 111.90%.