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Item Seed production of clones PB 86, RRIC 100 and RRIC 121 in three rubber growing areas of Sri Lanka(Rubber Research Institute. Agalawatta, 1997) Seneviratne, P.; Nugawela, A.; Amaratunge, K.A.G.B.; Karunasena, R.P.; Wilbert, S.The rubber seed production in wet rubber growing areas in Sri Lanka has gone to very low levels in the recent past affecting the culling process that should be adopted in establishing rootstock nurseries.From the three rubber growing areas studied satisfacton seed production irrespective of the clone was observed only in Kegalle region.Regional differences may be due to direct or influences of the climate and weather during flowering and pod set. Clonal differences seems to be existing in regions where climate or the weather is favourable for spread of diseases.Further RRIC 100 being a resistant clone for oidum and phytopthora.produced a higher percemage of good quality seeds compared with the other two clones.PB 86 and RRIC 121 which have below average tolerance to these two diseases.However currently country as a whole produces enough seeds to fulfill country's annual seed requirement for the production of rootstocks provided the seeds are collected and transported without delayItem Contour and East-West row planting systems or rubber (Hevea) for intercropping part III. light availability in the inter row space(Rubber Research Institute. Agalawatta, 2003) Pathiratna, L.S.S.; Perera, M.K.P.Item 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.Item Factors affecting the budgrafting success and the scion growth of young budding of Hevea(Rubber Research Institute. Agalawatta, 1994) Seneviratne, P.; Nugawela, A.; Samarakoon, S.M.A.The size of the bag in which the stock plant is grown seems to have an effect on the growth of the seedling; from the three bag sizes tested, ie 15 x33 cm, 18 x 38 cm, 23 x 45 cm, it was found that the diameter the number of leaf whorls of the seedling increased with the increase of the bag size.Though the differences are not statistically significant, the budding success too increased in the same pattern. There was no effect of the bag size on the growth of the scion. The two types of buds, axillary scale, showed no difference either on bud grafting success or on the growth of the scion. The growth stage of the top most leaf whorl of the stock plant, either mature or immature, had no effect on the peeling qualities budgrafting success though a little higher budgrafting success was seen when the top flush was immature. There was an effect of the snag, on the scion growth; when the snag was shorter the sprouting took place earlier but, the scion growth was slightly poor as was evident by the diameter the length of the scion. Long snags delayed the sprouting , but the scion growth was better. The best growth of the scion was obtained when the snag was long with a few leaves attached to it.Item Attributes of the bark cracking disorder in the root stock of bud grafted rubber (Hevea) trees(Rubber Research Institute. Agalawatta, 2007) Pathiratna, L.S.S.Item A brief overview of the tree crop sector in Sri Lanka during 1995-1999(People's Bank, Research Dept. Colombo, 2001) Marambe, B.Item Extended cost benefit analysis and ecological capital value of rubber (Hevea brasiliensis)(Postgraduate Institute of Agriculture, University of Peradeniya:Peradeniya, 1996) Naranpanawa, D.N.; Naranpanawa, A.K.B.; Samarappuli, I.N.; Bogahawatte, C.Item Rubber plantations as self-sustaining agroforestry systems(Sri Lanka Forest Department:Battaramulla, 1995) Samarappuli, L.; Yogaratnam, N.Item Estimation of rubber price returns using quantile regression(Postgraduate Institute of Agriculture, University of Peradeniya:Peradeniya, 2015) Nyantakyi, K.A.; Pieris, B.L.; Gunaratne, L.H.P.Item Some aspects of biochemical changes due to maturation of acid and papain treated Hevea latex(Rubber Research Institute. Agalawatta, 1998) Dissanayake, W.; Yapa, P.A.J.Biochemical changes that occur due to maturation of acid and papain treated Hevea latex were investigated. An increase in bacterial population in latex of both acid and papain treated, was significantly higher than that in acid treated latex. Higher microbial activity correlated with decreases in carbohydrate and amino acid levels in serum. Maturation of papain treated latex, enhances protein digestion and reduction in ash content without any adverse effect on major raw rubber properties.