ALS is specifically involved in Ol-1 -mediated resistance against Oidium neolycopersici ( On ). (A), Phenotype of NIL-Ol-1 plants in soil to which acetone (+ Acetone) or chlorsulfuron dissolved in acetone (+ Chlorsulfuron) has been added, and close-up of On development on the leaves. (B), Relative On fungal biomass on NIL-Ol-1, Moneymaker (MM) and NIL-Ol-4 plants grown in soil to which water (H2O), acetone or chlorsulfuron has been added. For each plant DNA was extracted from pooled 3rd and 4th leaves. Values are normalized relative to EF, and calibrated to level on plants grown in soil with acetone. Error bars represent three biological replicates for H2O and acetone treatments respectively, and 5 or more replicates for chlorsulfuron treatment. Two independent experiments were performed with similar results, and data from one experiment are presented. Asterisk indicates significant difference from the controls according to one way analysis of variance (P <0.05). (C), Relative On fungal biomass on NIL-Ol-1, MM and NIL-Ol-4 plants as in Panel B, but calibrated to the level on water-treated MM plants.