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Item Soil erosion. the present position(Tea Research Institute. Thalawakele, 1931) Eden, T.Item The effect of post prune operations on soil physical properties and yield of tea(Tea Research Institute. Talawakele, 1997) Amarasekera, A.R.; Abeysekera, U.P.; Anadacoomaraswamy, A.Item Effect of combined nitrogen on growth and nodule function or Pueraria phaseoloides(Rubber Research Institute. Agalawatta, 1991) Jayasinghe, C.K.; Wettasinghe, D.S.Nodulation and nitrogen fixation rates of most of the legumes are reported to be severely affected when they are grown in soils high in available nitrogen. Furthermore, this phenomenon may become more critical when legumes are grown in multiple cropping systems like Pueraria phaseoloides in rubber plantatons where ono legume counterpart is fertilized with nitrogenous fertilizer. Results of experiments conducted in seeding agar to find the effect of nitrogen on growth and nodule function of P. phaseoloides showed that nodulation of P. phaphaeoloides was inhibited at a concentration between 24.4 and 44.8 ppm nitrogenItem Effect of incubation time on acetylene reduction activity of common cover crops of Sri Lankan rubber plantation(Rubber Research Institute. Agalawatta, 1989) Jayasinghe, C.K.; Parker, C.A.; Kulasooriya, S.A.A wide range of incubation time from a few minutes to severl hours have been used with defferent plant systems in investigations on acetylene reduction assays. However, the duration of incubation period is of utmost importance in obtaining nitrogen fixation estimates using this technology. Time course experiment showed that acwtylene reduction by nodules of P. phaseoloides and D. ovalifolium started without a lag but rate of the nitrogenasse activity was reduced 4 hours after incubation while M. invisa showed a considerable activity even at the 8th hour of incubation. In the second experiment which was conducted to observe the relationship between acetylene reduction activity and incubation time upto one our, there was a linear relationship for both P. phaseoloides (r = +0.9832) and D. ovalifolium (r = + 0.99961)Item Splash erosion(Coconut Research Institute:Lunuwila, 1951) Francis, K.M.Item A leaf spot disease of Crotalaria spp(Tea Research Institute. Thalawakele, 1970) Shanmuganathan, N.Item Litter accumulation from Mucuna bracteata cover crop and its effects on some soil chemical properties in rubber plantations(Rubber Research Institute. Agalawatta, 2010) Chathurika, S.; Samarappuli, L.; Mapa, R.B.Item Breaking dormancy in seeds of cover legumes(Rubber Research Institute of Sri Lanka. Agalawaththa, 1976) Waidyanatha, U.P. de S.; Ariyaratne, W.A.Item Conservation of residual Nitrate Nitrogen with winter cover crops(Postgraduate Institute of Agriculture, University of Peradeniya:Peradeniya, 1998) Fernando, M.F.S.W.; Mosley, A.R.; McMorran, J.P.; Clough, G.Item Diurnal variation in nitrogenase activity of common cover crops in rubber plantations of Sri Lanka(Rubber Research Institute. Agalawatta, 1989) Jayasinghe, C.K.; Parker, C.A.; Kulasooriya, S.A.Diurnal fluctuations in nitrogenase activity (acetylene reducing activity) have been observed in several nitrogen fixing systems. All experimental plants viz. P. phasides D. ovalifolium and M. invisa demonstrated diuanal rhythm withlight intensity. The lowest acetylene reduction activiteswere detected around midnight and they were activelyu fixing nitrogen by 8.00 am. M. invisa responded to high soil temperature in addition to light intensity. A marked drop in acetylene reduction activity was observed by about 4.00pm when the soil temperature was around 38ºC