Linear relations among traits in off-season soybean

Abstract

In the highlands of Rio Grande do Sul, Brazil, with subtropical climate, the cultivation of the second summer crop with soybean (off-season), sowed after maize, has been adding economic importance, increasing progressively its cultivation area, and allowing greater grain yield during the summer period. Studies of traits of genotypes sown in this particular condition, with reducing luminosity effect, can assist in future selections in soybean plant breeding programs. The objective of this study was to evaluate the linear relations among soybean traits (Glycine max L.) and identify traits for indirect selection in the second crop of summer cultivation, in subtropical region. Eighteen soybean cultivars were evaluated in three locations of Rio Grande do Sul. Sowing was performed on Jan/09/2013, Jan/10/2013, and Jan/24/2013 for the experiments carried out in Barra do Guarita, Vista Gaúcha, and Tenente Portela, respectively. The randomized block design with four replications was utilized. The traits insertion of the first pod height, plant height, one hundred grains weight, and grain yield were measured. The traits analysis of variance was performed. Relation among traits was investigated through correlation and path analysis. In off-season soybean cultivation (second summer crop) in subtropical climate, plant height has positive linear relation with grain yield and it can be used for indirect selection of more productive cultivars.