[Response of seed germination of three xeromorphic shrubs to drought stress].

The seed germination, seedling growth and water absorption characteristic of Caragana korshinskii, Hedysarum scoparium, and Artemisia sphearocephala were investigated under different osmotic potentials (PEG 6000, -0.3(-) -2.7 MPa). The results showed that under drought stress, C. korshinskii had the highest germination rate, while A. sphearocephala had the lowest one. Under -0.3(-) -0.6 MPa, the root length of 10-day-old A. sphearocephala seedling was significantly longer than that of H. scoparium and Caragana korshinskii(P < 0.05), and the length reached 7.9, 4.5 and 3.1 cm, respectively. There existed a significant positive correlation between seed germination rate and 72 h water absorption rate of the three shrub seeds(P < 0.01). The relationships among germination characteristics, root length, and survive percentage of seedlings were also discussed.