Environmental conditions including metrological parameters (precipitation, temperature, humidity and etc.) various stresses and nutrition, could affect germination and seeds vigor during of development, ripping and leven after harvesting of soybean seed. For this, experiments of completely randomized design ( as Nested)by four replications were performed in seed laboratory of Gorgon University of Agricultural Science and Natural Resources. Treatments were 14 seed ladings of four soybean cultivars viz. of DPX (Gorgan, Gonbad, Azad-shahr Ali-abad and Kurd-koy), Sahar (Gorgan, Gonbad, Sari, Babolsar, Ali-abad and Kurd-koy), Williams (Ardabil; Gonbad) and Hill (Sari). First, standard germination and seedling growth test and then, accelerated aging test were done following by standard germination and seedling growth on degraded seeds. Results showed that environmental conditions have been caused different classes of seed vigor in seed ladings of every cultivar. Among 5 lading of DPX cultivar, Gorgon and Kurd-kuy ladings had the most and least seed vigor respectively. Babolsar and Sari ladings were superior than others in Sahar cultivar in respect to seed vigour and Kurd-kuy ladings had the least vigor (EC=26.46 µs. cm-1). Among Williams’s ladings, Ardabil lading had the most germination percentage and the least Electrolyte leading. There was significantly negative correlation between results of electrical conductivity test and seedling growth and normal seedling percentage test. Therefore, it seems that more farmer knowledge of farmers on site-specific and these environmental conditions could result in different seed vigor in the same cultivar. Environmental conditions help to select suitable area for seed production.
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