Genetic divergence and phosphorus use efficiency in the soybean with a view to biodiesel production

The soybean has an important role in the area of biodiesel, due to having a productive potential and technical feasibility able to meet the growing demand for renewable fuels. In the agricultural year of 2009/10, four competitive trials of soybean cultivars were carried out, two on the Campus of Palmas University and the other two on the University Campus at Gurupi, with a study of genetic divergence being undertaken. At each location, the cultivars were trained under conditions of both high and low phosphorus (150 kg ha-1 P2O5 and 30 kg ha-1 P2O5 respectively). The experimental design employed for each trial was of randomised blocks with three replications and 11 treatments. The percentage of oil as a characteristic was studied, and the efficiency of phosphorus usage by the cultivars determined employing the methodology adapted from Fischer (1983). Genetic divergence was evaluated using multivariate procedures: the generalised Mahalanobis distance and Tocher's optimisation method for clustering. In the study of genetic divergence, each test represented a distinct variable in the multivariate model. The cultivars M-SOY 9350, M 8766RR and BR/EMGOPA 314 are the most suitable for the production of biodiesel. The hybrids M 8766RR x M 9056RR, BR/EMGOPA 314 x M 9056RR, P98R91 x M 9056RR are promising for obtaining segregating populations to be used for their oil content