Temperature is one of the fundamental parameters to determine plant growth rate and production. The main aim of this study was to evaluate the emergence response of Persian shallot (Allium altissimum) to temperature by cardinal temperatures calculation. We used three regression models including intersected-lines, five-parameter beta and quadratic polynomial. This study was performed on ten temperature treatments including 6, 9, 12, 15, 18, 20, 22, 24, 26 and 28°C. The results showed that the highest Persian shallot emergence rate was gained under 18°C. However, increasing the temperature of growth environment sharply decreased the emergence rate of Persian shallot. In conclusion, fiveparameter beta model showed highest accuracy in prediction of Persian shallot emergence response to temperature (R2 =0.99**). Base temperature (Tb), optimum temperature (To) and maximum temperature (Tm) were 3.3, 17.0 and 29.5°C, respectively based on five-parameter beta model calculation.

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