the plumule and the radicle emerge, is called germination [5] . Seed germination is considered one of the sensitive stages in the life cycle of plants because it plays a major role in determining the final plant density. Factors such as gene control, seed size, viability, depth of planting, soil moisture, oxygen concentration, and temperature, influence on germination and seedling emergence [6] [7] [8] . Temperature is the most important driving force influencing crop development rate [9] . The

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... effects of temperature on plant development are the basis for models used in predicting germination timing [10] . Temperature and moisture are among the very important environmental factors in the germination of non-dormant seeds [11, 12] . These two factors, singly or in combination, can influence on germination percentage and rate [13, 14] . Plants have base or minimum, optimum, and ceiling temperatures for seed germination. The minimum or base temperature is the lowest temperature which seeds can be germinated. The optimum temperature is the temperature which seeds ratch its highest germination rate, and the maximum or ceiling temperature is the temperature above which seeds cannot germinate [15, 16] . Use of cardinal temperatures makes it possible to estimate geographical limitations and select the suitable time before planting seeds [16] . Cardinal temperatures of germination usually depend on the range of adaptability of the related species and insure the coincidence of germination with desirable conditions for the following stages of development [12] . Seed germination of any plant takes place in a specific range of temperatures called the Abbreviations