Artemisia monospermaachene germination in sand: effects of sand depth, sand/water content, cyanobacterial sand crust and temperature

The mucilaginous achenes ofArtemisia monosperma, a dominant perennial shrub in sandy deserts, germinate in light but poorly in dark. The deeper the achenes in sand, the lower and slower their germination. No seedlings emerged from deeper than 4 cm, but seedlings emerged after removal of the upper 3 cm or when exposed to light from below. In natural conditions seedlings emerge from a depth of 0•1 to 1•8 cm. The higher the sand/water content, the earlier the germination. The date of achene maturation also affects germination. Germination is inhibited on cyanobacterial sand crust and at 0•5 cm to 1 cm below this crust, even if aerated.