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A clear understanding of the mechanisms involved in releasing seed dormancy is important for effective plant conservation and regeneration of desert species. The dormancy types and dormancy release mechanisms of 19 Fabaceae species from four cold deserts in Xinjiang province, China, were studied. An imbibition experiment was performed to determine the presence or absence of physical dormancy. Other treatments included mechanical scarification, sulphuric acid scarification and simulation of summer temperatures typically encountered in the field. High summer temperature treatments included a maximum soil temperature of 80 degrees C, 65 degrees C and 40 degrees C, conducted under dry and wet conditions. The results showed that all the species had orthodox seeds. Caragana korshinskii, Caragana intermedia, Caragana microphylla and Onobrychis taneitica seeds were not dormant. Glycyrrhiza uralensis, Ammodendron bifolium, Vicia costata and Eremosparton songoricum seeds had combinational dormancy (PY _ PD) whereas the other 11 species had physical dormancy. The mechanical scarification and sulphuric acidscarification treatments were significant to break dormancy (>80%). Melilotus suaveolens and Oxytropis sp. seeds were temperature-insensitive. Sophora alopecuroides, S. salsula, E. songoricum, A. bifolium and Cassia tora seedswerewet-heat sensitive. Glycyrrhiza glabra seeds were dry-heat sensitive, while those of Halimodendron halodendron and Astragalus lehmannianus were sensitive to both dry and wet heat. Although high temperatures, typical of summer, promoted the breaking of physical dormancy, the proportion of seeds of which dormancy was broken differed among species. These differences were indicative of the conditions in which the species are found naturally. Species may have different adaptations that promote favourable regeneration. Given suitable temperature and moisture conditions similar to those in their natural environment, most species were capable of regeneration.