COCOS - Journal of the Coconut Research Institute of Sri Lanka
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Item Alternative methods to determine plot sizes for tree crops. a case study from coconut data(Coconut Research Institute of Sri Lanka. Lunuwila, 1997) Peiris, T.S.G.; Thattil, R.O.Two methodologies are pooposed to determine the most efficient plot size for tree crops using data from experiments based on randomized complete block designs. Both methods can be generalized for data from any balanced design. The merits and demerits of these methods are discussed. The methods are illustrated using the data sets of long-term field ecperiments at the Coconut Research Institute, Sri Lanka. The results show that efficient plot size in field experiments for coconut for a wide range of agroecological regions is four or six palms.Item An alternative model to estimate solar radiation(Coconut Research Institute of Sri Lanka. Lunuwila, 1994-95) Peiris, T.S.G.; Thattil, R.O.Solar radiation is extremely useful in modelling many agricultural applications, but is hardly used due to the difficulty in obtaining data, and the time consuming process in estimating it by the angstrom (1924) formula which uses world geographical relationships. To estimate solar radiation at the Coconut Research institute, Lunuwila (7o 20'N;71o 53'E;30.5m) an alternative model was developed from measured sunshine hours data only. The model had good fit (R2=0.90,P0.001) and was found to have agreement with the estimates obtained from the Angstrom model. The alternative model is more flexible and useful in estimating crop evapotranspiration, and for crop-weather modelling. The mean daily solar radiation at Lunuwila was estimated to be 18.3 MJ m-2d-1 and the total annual solar radiation receipts is 6680 MJ m-2 (66.8 TJ ha-1). The monthly solar radiation was highest in March (21.7MJ m-2 d-1) and the estimated 75 per cent probability value was 22.5 June had the lowest (16.1 MJ m-2 d-1) value and the estimated 75 per cent probability value was 17.8.Item Approach to screen coconut varieties for high temperature tolerance by in-vitro pollen germination(Coconut Research Institute. Lunuwila, 2010) Ranasinghe, C.S.; Waidyarathna, K.P.; Pradeep, A.P.C.; Meneripitiya, M.S.K.Item An assessment of labour availability in major coconut growing areas in coconut triangle(Coconut Research Institute. Lunuwila, 2010) Pathiraja, P.M.E.K.; Fernando, M.T.N.; Abeysekara, A.W.A.D.R.; Subasinghe, S.D.J.N.Item Assessment of the effects of environmental factors on yield of coconut (Cocos nucifera L.)(Coconut Research Institute of Sri Lanka. Lunuwila, 1997) Peiris, T.S.G.; Thattil, R.O.The long term nut yield data and climate data of eight variables (1976-1992) were analyzed to understand the effects of climate and weather on the yield variability between picks. The yield variation over the years had no systematic pattern. The order of contribution of the picks to total yield is not significantly consistent between years. Explanatory models were developed at monthly lag periods prior to harvest of each pick. The most and least influential picks in respect of climate variability are picks 5 and 2 respectively. The critical period with respect to climate and weather variability of picks 1-6 are February , June July, Septermber, December and February respectively. The climatic models fitted at these periods explain the yield variability between picks. The influence of climatic variables during these periods vary from pick to pick. Maximum air temperature and relative humidity in the afternoon are the two most significant environmental variables influencing yield irrespective of picks.Item Available soil phosphorus in coconut plantations in boralu and pallama soil series, under different fertilizer regimes, in Gampaha district of Sri Lanka(Coconut Research Institute. Lunuwila, 2007) Jayakody, J.A.D.S.S.; Tannakoon, N.A.; Fernandopulle, M.N.D.Item The brown dwarf. a recent addition to the varieties and forms of the coconut palm grown in Sri Lanka(Coconut Research Institute. Lunuwila, 1996) Peries, R.R.A.Item The brown dwarf. a recent addition to the varieties and forms of the coconut palm grown in Sri Lanka(Coconut Research Institute of Sri Lanka. Lunuwila, 1997) Perera, L.; Peries, R.R.A.; Padmasiri, M.H.L.Item Callus induction and direct shoot formation in in vitro cultured immature inflorescence tissues of coconut(Coconut Research Institute of Sri Lanka. Lunuwila, 1997) Vidhanaarachchi, V.R.M.; Weerakoon, L.K.Abstract link with word file.Item A case study on physiology -based drought screening of coconut with selected accessions(Coconut Research Institute. Lunuwila, 2007) Nainanayake, A.D.; Morison, J.I.L.Item Classificatin of farmers adopting coconut -based intercropping systems in small -holdings using cluster analysis(CRI. Lunuwila, 2000-2002) Fernando, M.T.N.; Daw, M.E.; Edwards, I.E.; Glendinning, A.Item Coconut breeding in Indonesia -1(CRI. Lunuwila, 1986) Liyanage, D.V.; Mankey, T.; Luntungan, H.; Djisbar, A.; Sufiani, S.Item Coconut breeding in Indonesia-II. the yield potential of improved varieties of coconut(Coconut Research Insitute. Lunuwila, 1987) Liyanage, D.V.; Luntungan, H.; Mankey, T.Item Coconut breeding in Sri Lanka:a review(CRI, 1988) Liyanage, D.V.; Wickramaratne, M.R.T.; Jayasekara, C.Work done by Coconut Research Institute, Sri Lanka, on the genetics and breeding of the coconut palm from 1930 to 1980 is described.Item Coir fibre pith as a ground cover in coconut plantations of Andigama shallow soils in Sri Lanka . an ex-post financial analysis(Coconut Research Institute. Lunuwila, 2005) Jayalath, K.Y.N.N.Item A comparative study of water movement in leaf scorch decline affected and healthy coconut palms using lithium as a non-radioactive tracer(Coconut Research Institute. Lunuwila, 2007) Madurapperuma, W.S.; Mendis, H.; Ranasinghe, C.S.; Premasiri, N.; Gunawardena, M.Item A comparison of two coconut cultivars for high productivity under irrigation(Coconut Research Institute of Sri Lanka. Lunuwila, 1994-95) Peries, R.R.A.Over four decades of research indicate that the cultivar CRIC65 is capable of producing a sustained higher yield compared to CRIC60 inthe absence of adverse soil water deficit. Data indicate that the cumulative yield of nuts and copra are 50 per cent higher in CRIC65 than in CRIC60 over a period of 32 years. Inadequate soil water would appear to be the main limiting factor to the yield production in CRIC65. The argument is, therfore made, that if coconut is to be grown under irrigation, the cultivar CRIC65 should be selected due to its high potential productivity.Item Competitive effects of weeds and beneficial effects of mulching on coconut seedlings(Coconut Research Insitute. Lunuwila, 1987) Remison, S.U.; Mgbeze, G.Item Copra drying in an improved solar dybrid system, CRI improved kiln and in the sun. a comparative study of drying characteristics(Coconut Research Institute of Sri Lanka. Lunuwila, 2005) Thanaraj, T.; Dharmasena, D.A.N.; Samarajeewa, U.Item Culture of immature embryos of coconut, Cocos nucifera L.. callus poliferation and somatic embryogenesis(Coconut Research Insitute. Lunuwila, 1990) Karunaratne, S.; Periyapperuma, K.