关键词: 休眠, 抗旱, 以色列, 野生二棱大麦, 微环境

Abstract: Wild barley, Hordeum spontaneum, is the progenitor of cultivated barley(H. vulgare).The depth of caryopsis dormancy(germinability) and seedling drought-tolerance are extremely important characteristics of H. spontaneum in the Mediterranean climate.The dormancy depth and seedling drought tolerance of wild barley were investigated at three microsites of "Evolution Canyon", Israel.The south-facing slope(SFS) presents the xeric and warmer habitat, the north-facing slope(NFS) presents the mesic and cooler conditions, and the ecological factors at the bottom area of the canyon are between SFS and NFS.The obtained results showed that caryopses from SFS had significantly deeper dormancy than those from the NFS.Moreover, the seedling revival ability after periods of drought resistance was also significantly higher in caryopses collected from the SFS than from NFS sites, whereas the dormancy and seedling revival ability at the bottom of the canyon showed an intermediate inter-slope pattern.Thus, dormancy depth is positively and significantly correlated with seedling revival after drought.These results display that the microhabitat environment is the dominant adaptive factor in the natural selection for seeds dormancy as well as seedlings drought tolerance of wild barley, and it overrides any inters-lope migration and parallels regional patterns across Israel.

Key words: dormancy, drought tolerance, Israel, wild barley (Hordeum spontaneum), microhabitat