BioassaysHevea brasiliensis leaves (clone PB260, sensitive to Corynesporacassiicola strain CCP) in the morphogenetic stage D [13]were detached and placed on water-soaked filter paper in largePetri plates, abaxial side up. The lower epidermis was gentlyscraped (over 1mm2) using a scalpel blade and one dropof the tested sample (10 or 15l) was placed on the superficiallywounded spot. Drops of chromatography buffers wereused as negative controls, in appropriate dilution to, reproducethe solution of the tested sample after elution. The plates weremaintained for 48–96 h at 25 ◦C (photoperiod 12 h) until symptomswere clearly visible.