Description of the environmental damage on soybean seeds [Glycine max (L) Merr].

Since 1996, an intensification of the environmental damage on soybean seeds has been observed in Argentina as well as the appearance of new manifestations that differ from the traditional pattern. The main objective of this study was to describe these new manifestations and the intensity of environmental damage on soybean seeds. Seeds from Pioneer 9492 RR cultivar, produced in 2001, in Oliveros, Argentina, were harvested and threshed manually. Seeds were subjected to the tetrazolium test using 16 replicates of 50 seeds each. Seed samples were placed in wet paper towels rolled at room temperature for 18 hours. Later, seeds were incubated in 0.075% 2, 3, 5 triphenyltetrazolium chloride solution for 3 hours at 38 C. Seeds were evaluated individually and cotyledons observed internally and externally. The following data were recorded: presence, type, location and depth of the traditional environmental damage (T) and the new manifestation, which was called non-traditional (NT). The latter was characterized by areas of damaged and/or dead tissue, which were randomly distributed over the cotyledons. In some cases, areas of damaged tissue inside the cotyledon, but without external manifestations, were observed. Unlike T, NT neither appeared at the periphery nor did it show the symmetry and homology, both characteristic features of the T. The description of the NT would allow these new manifestations to be incorporated to the T pattern in the tetrazolium test.