Mirissala, B.G.C.D.K.Herath, H.M.S.KNainanayake, N.P.A.D.2022-03-212022-03-212013http://www.erepo.lib.uwu.ac.lk/bitstream/handle/123456789/8523/33-PLT-Evaluating%20Root%20Distribution%20Pattern%20of%20Selected%20Coconut%20Cultivars%20at%20Seedling%20.pdf?sequence=1&isAllowed=yCoconut is one of the main commercial plantation crops in Sri Lanka. Annual National Coconut Production (ANCP) in Sri Lanka is more or less stagnant or with only a slight increase during last two decades. Human inhabitation and climatic change are the main contributory factors that affected on reducing extent of coconut growing lands in traditional areas and led to promote coconut cultivation in non-traditional areas. Therefore, identification of a coconut cultivar/s with putative drought tolerance is of a paramount importance.Strong and well distributed root system is of extremely important in withstanding frequent dry spells experienced in marginal areas especially in dry zone. This led to the present investigation on root distribution pattern of selected, improved coconut cultivars grown under different climatic and soil conditions. The experiment was conducted (i) to identify the root distribution pattern of CRISL 98 (a cross between Tall and San Ramon) and Kapruwana (a cross between Dwarf Green and San Ramon) cultivars at seedling stage under different climatic and soil classes and also (ii) to identify their active root zones and their variation under different environments. Methodology Experiment was conducted as a three factor factorial using around 3 year old coconut seedlings of Kapruwana and CRISL 98cultivars under intermediate zone (IZ) and wet zone (WZ) in S1/S2 and S3/S4 land suitability classes (LSC). Soil core samples were taken from different distances (50, 100 and 150 cm) from the base of the seedling and at five depths in two opposite directions (20, 40, 60, 80 and 100 cm). They were separated in to two groupsviz. primaries and secondariesafter washedthe root samples.Then, number, dry weight, total root length (Tennant, 1975) and root volume (Herath, 2004) were measured for primary and secondary roots separately. Data were analyzed using ANOVA and means were separated using Duncan’s new multiple range test (DNMRT) using SAS (version 8) computer software.enAgricultureExport AgricultureCrop ProductionCoconutPlantationsOther