Browsing by Author "Pushparajah, E."

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    Determination of Active Root Distribution of Hevea brasiliensis using Radioactive Phosphorus
    (1971) Soong, N.K.; Pushparajah, E.; Singh, M.M.; Talibudeen, O.
    Phosphorus uptake by Hevea seedlings from nutrient solution and by mature Hevea trees from the soil was studied using P32 tracer. The usefulness of leaves and latex for detecting PM uptake by Hevea was compared. Latex assay was found to be more convenient and reliable than leaf assay and was used to determine the relative distribution of active roots of Hevea in three different soil zones under study. Maximum root activity was found to be in the first 12 feet from the trees, reflecting past cultural practices. Injection of P32 into the trunk of a mature rubber tree showed translocation into the leaves and latex but no radioactivity could be detected in the roots or in the surrounding soil indicating that trunk injection was unsuitable for estimating the distribution of active roots in soil.
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    A Thermodynamic Assessment of the Nutrient Status of Malayan Soils Quantity-Intensity Measurements for Potassium Using Calcium Chloride Equilibriation
    (1968) Mohinder Singh, M.; Tan, K.T.; Pushparajah, E.; Talibudeen, O.
    Quantity /Intensity (Q/I) relationships for potassium status of soils were determined in nine acid soils of Malaya which are known to have widely differing K-status and on which rubber Is commonly grown, by the calcium chloride equilibriation procedure of BECKETT. Quantity. Intensity and Buffer Capacity values derived from these Q/l relationships did not give better relation with the status of soil, as indicated by greenhouse cropping by Pueraria. than the conventional acid-extractable value. The best assessment parameter appeared to be a Buffer Capacity value (B. C. cropping), obtained from greenhouse cropping data and the laboratory measured intensity, although intensity, when taken alone is the poorest Indicator of soil K status as assessed by greenhouse cropping by Pueraria.