Genetics, phosphorus and correlations in soybean yield

It is essential to select soybean genotypes with high yield and adaptability to the Cerrado Biome, mainly related to the supply of phosphorus. In soybeans, studies on correlations involving their characters with phosphate fertilization are insipient. The objective of this work was to evaluate the phenotypic correlations of soybean under different concentrations of phosphorus, aiming to improve the selection and identification of the most promising characters regarding the possibility of gains in grain yield. The study was conducted in Mineiros, Goiás, Brazil. The experimental design used was in randomized blocks in factorial corresponding to four soybean genotypes in five levels of phosphorus. The soil tillage system was carried out conventionally. The crop treatments relevant to the control of weeds and pests were carried out following the best practices of integrated pest management. At the end of the experiment, the data were submitted to multivariate analysis of variance. The treatments differed, mainly due to the number of grains per plant, where their similars were grouped in clusters. The correlations between the characters were significant and pointed to affinities, in addition to the potential explanation for the yield. It is concluded that genetic factor is largely responsible for the soybean yield indices, however, this was also influenced by the concentrations of triple super phosphate as a phosphate source. And that in order to increase the yield of the soybean crop it is necessary to reduce the stand and plant height, as well as to increase the average of pods with three grains, pods per plant and grains per plant.