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Dormant Arabidopsis (<i>Arabidopsis thaliana</i>) seeds do not germinate easily at temperatures higher than 10&#8315;15 &#176;C. Using mutants affected in ethylene signaling (<i>etr1</i>, <i>ein2</i> and <i>ein4</i>) and in the N-end-rule pathway of the proteolysis (<i>prt6</i> and <i>ate1-ate2</i>) we have investigated the effects of cold and ethylene on dormancy alleviation. Ethylene (10&#8315;100 ppm) and 2&#8315;4 days chilling (4 &#176;C) strongly stimulate the germination of wild type (Col-0) seeds at 25 &#176;C. Two to four days of chilling promote the germination at 25 &#176;C of all the mutants suggesting that release of dormancy by cold did not require ethylene and did not require the N-end-rule pathway. One mutant (<i>etr1</i>) that did not respond to ethylene did not respond to GA₃ either. Mutants affected in the N-end rule (<i>prt6</i> and <i>ate1-ate2</i>) did not respond to ethylene indicating that also this pathway is required for dormancy alleviation by ethylene; they germinated after chilling and in the presence of GA₃. Cold can activate the ethylene signaling pathway since it induced an accumulation of <i>ETR1</i>, EINI4, and <i>EIN2</i> transcripts, the expression of which was not affected by ethylene and GA₃. Both cold followed by 10 h at 25 &#176;C and ethylene downregulated the expression of <i>PRT6</i>, ATE1, ATE2, and of <i>ABI5</i> involved in ABA signaling as compared to dormant seeds incubated at 25 &#176;C. In opposite, the expression of <i>RGA</i>, GAI, and <i>RGL2</i> encoding three DELLAs was induced at 4 &#176;C but downregulated in the presence of ethylene.