Effects of alternative extracts in the agronomic performance of two soybean cultivars

The soybean cultivation along the years has required big investments and high technological level to develop new and more productive cultivars. However, the advent of biotic stress, such as diseases, can lead to losses in yield. To attenuate this interference and obtain the expected yield, chemical products have been used to control these diseases. This technique has shown good efficiency in short-term, but can damage the environment and promote the appearance of resistant biotypes in the long-term. So, alternative methods of diseases control, such as pyroligneous extract and the fungus Pycnoporus sanguineus have been used in soybean and other cultures to control diseases without the prior negative aspects of chemical products. The aim of this study was to evaluate possible interferences of these treatments in the agronomic performance of soybean culture. The experiment was conducted in the 2012/2013 harvest, submitting two soybean cultivars to pyroligneous aqueous extract in the 0.6 and 1.3% concentrations and the fungus P. sanguineus extract in the 2.5 and 5% concentrations, thus comparing their results with a  positive control and water control treatment. The results showed that the 2.5% fungus concentration statistically reduced the yield of the Turbo RR® BMX cultivar and the 5% fungus concentration reduced the grain mass of Vmax RR® NK 7059. The pyroligneous extracts reduced the number of pods of the Turbo RR® BMX cultivar and the height of Vmax RR® NK 7059, but did not affect the yield. In either cultivar, the plant growth regulator obtained the best results for all characteristics.   Key words: pyroligneous, Pycnoporus sanguineus, plant growth regulator.