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Item Mycoflora associated with Hevea phylloplane(Rubber Research Institute:Agalawatta, 2000) Jayasinghe, C.K.Item Toxic metabolite from clove isolate of Cylindrocladium quinqueseptatum(Rubber Research Institute:Agalawatta, 1999) Jayasinghe, C.K.; Wijesundera, R.L.C.Cylindrocladium Quinqueseptatum Boedijn Reitma causes seedling blight and extensive defoliation on a wide variety of plants and is widely distributed in the humid tropics.It is a serious pathogen of Eugenia caryophyllata in Sri lankaand has been identified as a potential lpathogen on Hevea brasileensis in the eastern Hemispher .All cloveisolates;IMI 342173 (rt),359378(Aw),359379(Rw)and 359380(Kp) of c.quinqueseptatum tested were found to be capable of secreting toxic substances to the growing medium.Toxic culture filtrates proved to be thermostagbl4e(up to 100C)and host specific.The type and the size of the lesions lproduced by the crude toxin of different isolates varied markedly.Isolate,Rt produced the largest lesions (Highest score) indicationg its aggressive nature in toxin production while Aw and Rw isolates showed a mild reaction.When the reaction of Hevea clones towards the crude toxin was considered three main clusters ofclones were distinguished through cluster analysis indicationg the marked variation of Hevea clones grown in the Eastern Hemisphere in their sensitivity to the crude toxin.The possibility of making use of this toxin as a tool in screening Hevea populations for cylindrocladium leaf spot disease has also been discussed.Item Cell wall degrading enzyme secretion by Cylindrocladium quinqueseptatum(Rubber Research Institute:Agalawatta, 1999) Jayasinghe, C.K.; Wijesundera, R.L.C.Cylindrocladium quinqueseptatum causes leaf fall of clove in Sri Lanka and is responsible for the leaf spots of rubber in Malaysia.only one isolate (KP)from four pathogenic isolates examined secreted polygalacturanase(PG) when grown in liquid media.None ofthe isolates secreted pectin lyase(PL).The extracts of clove and rubber leaf tissues,inoculated with the KP isolate did not show any PG and PL activity .The leaf tissue did not have the ability to ingibit c.quinqueseptatum PG produced in culture.All isolates of C.quinquesepltatum secreted cellulases viz.cellobiase and b-glucosidase in culture.cellobiase was detected in the inoculated rubber leaves,The levels of B-glucosidase,an ingerent enzyme of Hevea leaves,also increased rapidly following infection.The results indicate that pectic enxymes play a minimal or no role in disease developmet of C.quinqueseptatum infecton in cloves and Hevea.Thus cellulolyic enzyme probably play a nutritive role.Item 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.Item Cultural characteristics and reproductive morphology of Geotrichum sp.. a guide to distinguish Geotrichum from Rigidoporus microporus(Rubber Research Institute:Agalawatta, 1998) Jayasinghe, C.K.; Wettasinghe, J.L.P.C.Culture characteristics of Geotrichum sp. isolate IMI 354411, a fungus responsible for the saprophytic colonization on Hevea roots are described. It was also shown that this fungus could be easily distinguished from Regidoporus lignosus, a devastating pathogens of Hevea roots, by the zonate and cloudy appearence of its colonies on malt agar with a cream undersurface and the disarticulating hyphae which later break upto arthric conidia.Item Cultural characteristics and reproductive morphology of Geotrichum sp.. a guide to distinguish Geotrichum from Rigidoporus microporus(Rubber Research Institute:Agalawatta, 1998) Jayasinghe, C.K.; Wettasinghe, J.L.P.C.Culture characteristics of Geotrichum sp. isolate IMI 354411, a fungus responsible for the saprophytic colonization on Hevea roots are described. It was also shown that this fungus could be easily distinguished from Regidoporus lignosus, a devastating pathogens of Hevea roots, by the zonate and cloudy appearence of its colonies on malt agar with a cream undersurface and the disarticulating hyphae which later break upto arthric conidia.Item 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.Item Changing scene of the disease scenario of the rubber tree in Sri Lanka. history and current status(Rubber Research Institute of Sri Lanka:Agalawatta, 2009) Jayasinghe, C.K.Item Corynespora leaf fall and future of the leading rubber clones in the world(Rubber Research Institute of Sri Lanka:Agalawatta, 2002) Jayasinghe, C.K.Item Check list of rubber diseases presently distributed in the world(Rubber Research Institute of Sri Lanka:Agalawatta, 2001) Jayasinghe, C.K.