Figure 6.

Concentration Dependence of Haustorial Induction and SaExp Accumulation.

Two-day-old S. asiatica seedlings (20 to 30 per well) were incubated with 10 μM (circles) or 2 μM (squares) DMBQ in 24-well culture plates; approximately every 2 hr, the DMBQ solution was replaced with double-distilled water in triplicate sets of wells.

(A) and (B) At 24 hr, seedlings were scored for either (A) haustorial development, with an enlarged tip and hairs, as in the photograph at top left (after 8-hr exposure to 10 μM DMBQ), or (B) root tip diameter, as in the photograph at bottom left (after 3-hr exposure to 10 μM DMBQ).

(C) and (D) SaExp1 and SaExp2, respectively, were measured in 2-day-old seedlings incubated with 10 μM (circles) or 2 μM (squares) DMBQ for the indicated times. Errors (based on variation between triplicate runs) are expressed as ±sd.