TY  - BOOK
AU  - Samarappuli Lalani
AU  - Lalantha H K L
AU  - Perera A M A
AU  - Rajapakse W
TI  - Distribution of Mn and Zn in rubber growing soils and its status in relation to selected management practices
PY  - 2000///
PB  - Journal of the Rubber Research Institute of Sri Lanka
KW  - Cover crops
KW  - Hevea
KW  - Micro-nutrients
KW  - Poultry litter
KW  - Rubber growing soils
KW  - Soil management
N2  - A study was undertaken to assess the distribution profile of manganese (Mn) and zinc (Zn) in rubber growing soils and its status in relation to some soil management practices. Among the micro nutrients, Mn and Zn are considered as important for rubber. The acid extractable Mn and Zn contents which are considered as indicators of Mn and Zn reserves in soil, indicated significant differences between soil types. Matale soil series recorded the highest concentration of acid-extracted Mn and Zn followed by Ratnapura and Parambe series soils. Other soil series studied had low contents of both Mn and Zn. The profile distribution of acid-extracted, total Mn content showed a decrease with increase in soil depth while Zn content showed an opposite trend. The Mn and Zn contents in A and B horizons also exhibited a similar tendency. There was a negative correlation between Zn content and soil organic carbon content. Assessment of Mn and Zn status in relation to some soil management practices indicated that rice straw and poultry litter application enhanced the soil and leaf Mn contents significantly. Application of rubber factory effluent to rubber lands and different planting practices such as rubber and tea and rubber and cinnamon multi-cropping systems on Mn and Zn status of rubber growing soils were also investigated. Leaf contents of both Mn and Zn of different legume cover species and their effect on soil Mn and Zn status were also studied. RRIC 100 series clones showed higher leaf Mn and Zn contents compared to clone PB86 at the same Mn and Zn soil levels
ER  -