Journal of the Rubber Research Institute of Sri Lanka

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    Susceptibility of different leaf stages of Hevea to Corynespora cassiicola
    (Rubber Research Institute. Agalawatta, 2010) Fernando, T.H.P.S.; Jayasinghe, C.K.; Wijesundera, R.L.C.; Siriwardena, D.
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    A comparative study of Colletotrichum species causing anthracnose in Hevea
    (Rubber Research Institute. Agalawatta, 2009) Jayasinghe, C.K.; Fernando, T.H.P.S.; Jayawardana, N.
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    Penta chloro phenol - effective and economical fungicide for the management of white root disease caused by Rigidoporus lignosus in Sri Lanka
    (Rubber Research Institute of Sri Lanka. Agalawatte, 1995) Jayasinghe, C.K.; Jayasuriya, K.E.; Fernando, T.H.P.S.
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    In vitro antagonism caused by some species of fungi on Rigidoporus lignosus
    (Rubber Research Institute. Agalawatte, 1996) Jayasuriya, K.E.; Deacon, J.W.; Fernando, T.H.P.S.
    Fungi potentially antagonistic to rigidoporus lignosus were isolated from a) by placing soil samples on agar plates previously colonized by R.lignosus, or on trichoderma selective agar and b) from basidiomycete fruit bodies in rubber plantations.Modes of action of potential antagonists against R. lignosus were evaluated by in vitro methods viz: production of volatile or non-volatile inhibitory compounds and ability to overgrow colonies of R. lignosus an agar. Some trichoderma spp. were strongly antagonistic to R. lignosus in most of the tests. T. longibrachiatum (isolate DZE10) completely inhibited R. lignosus an agar by producing volatile inhibitory metabolites. Trametes sp. producing volatile inhibitory metabolites. Trametes sp. (isolates ISO16 KIR8) antagonized R. lignosus on dual membered plates.
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    Weakening effect of 2-furaldehyde on Rigidoporus lignosus the cause of white root disease of rubber
    (Rubber Research Institute of Sri Lanka. Agalawatte, 1996) Jayasuriya, K.E.; Deacon, J.W.; Fernando, T.H.P.S.
    Furfuraldehyde is recognized as a potential fumigant which has the ability to weaken rigidoporus lignosus in artificially or naturally infected rubber root inocula. Addition of sulphur to soil at 100 g per 75 Kg of soil, inactivated or prevented the formation of R. lignosus mycelial cords from artificially or naturally infected inocula. Drenching 2.4 per cent aqueous solution of furfuraldehyde in to soil (1 liter/75 Kg) where R. lignosus inocula were buried, caused weakening or inactivation of R. lignosus in artificially or naturally infected inocula. However, combination of two treatments had no ssynergistic effect on both types of R. lignosus inocula in soil.
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    Production of cell wall degrading enzymes by Corynespora cassiicola in culture and infected rubber tissue
    (Rubber Research Institute. Agalawatta, 1998) Jayasinghe, C.K.; Fernando, T.H.P.S.; Priyanka, U.M.S.
    All isolates of Corynespora cassiicola used in the investigation secreted pectin lyase when grown in liquid medium with pctin as the main source of carbon. However, none of the isolates secreted polygalacturonase in the same medium. The extracts of rubber tissue inoculated and infected with C. cassiicola also showed only pectin lyase activity. When grown in liquid medium with carboxymethyl cellulose as the main source of carbon all isolates secreted cellulases viz. cellobiase and ß - glucosidase. The result of this study suggest that principal pectic enzyme involved in pathogenesis of the rubber isolates of C. cassiicola is pectin lyase and in the later stages cellulolytic enzymes possibly play a major role