Phenotypic correlations and path analysis between morphoagronomic and bromatological traits in corn hybrids for silage production

Abstract

The aim of this study was to estimate the correlation coefficients and slicing the phenotypic correlations into direct and indirect effects by path analysis between morphoagronomic and bromatological traits in corn hybrids for silage. Nineteen topcross hybrids and five controls were assessed in a randomized block design with four replications in two environments (Campos dos Goytacazes and Itaocara, RJ), in the 2013/2014 agricultural year. Phenotypic correlations and path analysis were estimated between morphoagronomic (average plant height; average first ear height; average stem diameter; ear yield with husk at silage point; grain yield at silage point; green mass yield) and bromatological (dry matter; crude protein; neutral detergent fiber; lignin; crude fat and mineral matter) traits. The highest correlation estimates were obtained between dry matter and crude protein and between dry matter and neutral detergent fiber, with magnitudes of 0.97 and 0.98, respectively. The coefficient of determination was high, indicating that the assessed components explain much of the variation in the dry matter content. Path analysis showed that traits with highest direct effect on dry matter content were the yield of green mass, crude protein, neutral detergent fiber, crude fat, and mineral matter associated to high correlations of 0.96, 0.97, 0.98, 0.90, and 0.96, respectively. The results showed the possibility of obtaining significant gains through indirect selection