Soybean seed is one of the important sources of oil and protein supply. Economical production of soybean seed mean sound seed accompanied by maximum rate of germination. Soybean seed cracks in shell during harvesting, cleaning, transport and during drying processes, causes decrease in germination rates. Limited information is availble to show the relationship between germination rate and drying temperature as well as drying depth. The objective of this research is to investigate the effect of drying air temperatures of 25, 30, 35 and 40°C as well as drying bed depths of 5 and 10 cm on cracking percentage in Sahar and Hill varieties. A factorial statistical design based on randomized complete blocks was used in this research work. The results showed that with an increase in drying air temperature from 25 to 40°C, the percentage of cracks increase from 12.95 to 43.80. With an increase of bed depth from 5 to 10 cm, crack percentage decreased from 27.9 to 24.3. Sahar variety was more sensitive than Hill with respect to cracks in shell. An inverse relationship was observed between the percentage of shell cracks and the rte of germination of soybean seeds with a coefficient of determination of 0.95. It can be concluded and recommended that a depth of 10 cm is more appropriate than 5 cm for drying of Hill and Sahar soybean varieties. The drying air temperatures of 30 and 35°C were the most suitable for Sahar and Hill varieties, respectively
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