Abstract: The seeds ofArabispaniculataand its relativeArabidopsisthalianawere used as materials in the present study. The germi-nation rate, the content of ABA and the accumulation of HSP101 and HSP70 were compared in these two species before and after treat-mentofmannitolwithdifferentconcentrations(150,300and600mmol /L). TheadaptationmechanismofA.paniculatato alpine en-vironment was discussed. The results were presented as following: the seeds ofA.paniculatawere more sensitive to the treatment of mannitol; temporary seed dormancy was exhibited inA.paniculatawhen the concentration of mannitol exceeded 300 mmol / L; the ABA content of the seeds inA.paniculatawas significantly higher than that inA.thalianaunder the normal growth conditions and mannitol treatment. The abundance of HSP101 and HSP70 was low in both species under normal growth conditions. The protein levels of HSP101 and HSP70 were increased rapidly under mannitol treatment inA.thaliana, while those were still kept low inA.paniculata.These results indicated that seed dormancy was induced inA.paniculataupon high accumulation of ABA to adaptation to alpine envi-ronment with limited water in winter. A energy conservation strategy was speculated according to the fact that the protein levels ofHSP101 and HSP70 were not affected inA.paniculataunder drought stress.K

Key words: Arabispaniculata, seed germination, seed dormancy, drought, ABA, HSP