GC FID (Gas Chromatography with Flame Ionization Detector) - Measurement * 3 pods and 3 sections of stem (10 cm) were collected from each plant, and inserted into Pyrex glass tubes (122 mm (L) x 19 mm (D), roughly 20 ml vol.). * Wax was extracted using chloroform. Chloroform was spiked with a C22:0 alkane and C17:0 fatty acid as internal standards. Internal standard concentrations were 10 µM in chloroform (giving 100 pmol/µl for GC injection). Wax was extracted for 30 seconds using 10 ml of the chloroform/IS mixture. Sample tubes were inverted continuously during the extraction phase. PTFE cap liners were used to ensure minimal extraction of plasticisers. * Pod and stem material are removed from the tubes, and samples dried under vacuum in a centrifugal evaporator (Genevac, EZ-2) at ? 42°C using program low BP. Samples can also be dried under a stream of nitrogen at ? 30°C. * Wax components were derivatized with 200 µl of BSTFA + TMCS (99:1) for 1 hour at 85°C. * After cooling, 800 µl of heptane was added (total vol. 1 ml), and 1 µl was injected onto the GC-FID/MS. * GC program: * Initial temp: 50°C, to 200°C at 50°C/min, to 280°C at 2°C min, to 325°C at 10°C/min, hold for 6.5 minutes. * Inlet temp: 280°C, split-less injection. * Column: HP-1MS UI, 30 m x 0.25 mm x 0.25 µm, flow = 1 ml/ min. * FID temp: 325°C acronym entity variable_of attribute scale_of method_of