Soybean seed moisture content and methods of evaluating the mechanical damage in the pendulum test

Abstract

Twelve soybean cultivars (Glycine max (L.) Merrill) were harvested and hand-threshed at R7 and conditioned to 9%, 11% and 13%, moisture content before to be stressed in the pendulum test, that applied a kinetic energy of 0.3185 joule on the seed. In the evaluation system of tetrazolium test a grade score was adopted to quantify the results, and for the sodium hypochlorite test the number of swelled seeds was used. Both methods prove to be accurated to identify the levels of resistance among the genotypes tested. The 13% moisture content allowed the best screening related to the mechanical damage resistance under the pendulum test, in the two evaluation methods (r = 0.95). The results confirm the possibility of utilizing the sodium hypochlorite tests as an alternative of low cost and easy made for the tetrazolium test, in the process of soybean genotype selection for the mechanical damage resistance under the pendulum test.