Weder Ferreira dos Santos

Adaptabilidade na produção de massa verde e grãos de genótipos de milho no Tocantins

Different growth conditions give genotypes a different response to each situation. To reduce the effect of this interaction, analyses of stability and adaptability are undertaken, which assist in choosing the genotypes. However, often a genotype can have a variety of purposes, causing problems to farmers in some situations, and the use of specific genotypes could be a solution. The objective of this research was to study the adaptability and stability of maize genotypes in the South Central region of the state of Tocantins, Brazil, and to classify them according to trends in productivity goals: grain or green weight. Eight experiments were conducted in two towns in Tocantins in the 2010 off-season and the 2010/2011 season, in which 16 maize genotypes were evaluated. The total plant green weight and grain production (g plant-1) were evaluated and then used in the analysis of stability and adaptability. Later it was sought to classify the trends in productivity goals for the genotypes. The genotypes P09, P12, P10, H02 and H01 displayed a superior classification of the regression coefficient for grain production compared to total plant green weight, with the opposite happening in the P02 and P01 genotypes. Genotype H01, as regards grain production, was adapted for favourable environments and displayed a tendency for this characteristic as a productive goal. Unlike the P08 and P02 genotypes that were adapted for both environments or for favourable environments respectively, as regards total plant green weight, and show a trend in productive goals for this characteristic.