Figure 1. HPLC and MS/MS analysis of strigolactone and zeatin and natural homologous pinelactone and zeatin identified from root exudates. Pinus greggii root metabolites exudated to the hydroponic culture were trapped in an activated-charcoal filter as indicated in materials and methods. Fractions were resolved by HPLC (left panel) and selected peaks were then resolved by MS/MS with electrospray-positive scan mode (right panel). Standards and natural exudates are indicated. Note the precursor ion for lactone, at m/z = 331 and the characteristic product ions (97, 216, 234), common in the 2 upper panels. For zeatin (3rd and 4th panel, the precursor ion is at m/z = 220, with the characteristic product ions (119, 136, 148); common for the standard and natural zeatin.