Produksi dan Inaktivitas In Vitro Toksin Isolat Corynespora cassiicola (Berk.&Curt.) Wei Asal Daun Karet

Abstract

Penyakit Gugur Daun Corynespora pada tanaman karet yang disebabkan oleh Corynespora cassiicola [Berk. & Curt.] Wei telah menjadi ancaman bagi produksi karet di Indonesia. Cendawan patogenik tersebut menghasilkan toksin yang dinamakan cassiicoloa yang berperan penting dalam patogenisitasnya. Hingga saat ini masih belum diketahui strategi pengendalian yang efektif dan efisien untuk mencegah epidemi penyakit tersebut

The Corynespora leaf fall disease on rubber caused by Corynespora cassiicola (Berk. & Curt.) Wei is a serious threat for rubber production in Indonesia. The fungus produces toxin called cassiicoline which play a role in pathogenicity of the disease. Up to now an effective and efficient strategy to control the epidemic of the disease has not been obtained yet. The objectives of this study are (1) to evaluate capability of isolates of C. cassiicola from rubber and non rubber hosts to produce toxin in vitro, and (2) to analyze factors that affecting the biological activity of toxin in relation with the plant defense to the disease, and (3) to evaluate the effectivity of several reducing agents to inactivate cassiicoline. Phytotoxicity of the toxin was determined by using a modified bioassay procedure namely bioassay in planta (BiP) to substitute test by using leaf cuttings.