Water stress can induce quiescence in newly-germinated onion (Allium cepa L.) seedlings

The effect of water stress on the early seedling growth of onions was studi ed by placing newly-germinated seedlings in vermiculite equilibrated at dif ferent water potentials. Roots and shoots elongated more at -0.29 than at - 0.64 MPa, but did not elongate at -1.66 MPa, However, roots and shoots of s eedlings that had been incubated in vermiculite at -1.66 MPa for up to 35 d resumed elongation when subsequently placed on wet filter boards. This sug gests that water stress can induce quiescence in newly-germinated seedlings .