2285 research outputs found
Sort by
Assessment of oxygen availability in soils of different drainageclasses and its effect on coconut root growth
No full textThe interaction between potassium and magnesium red yellow podzolic soils with laterite and its effect on nutrition of coconut palms
Get PDFThe interaction between plant available potassium and magnesium in highly leached red yellow podzolic soild with laterite in southern coastal area of Sri Lanka and its effect on coconut palm was studies in a 3*2K*Mg factorial experiment that consisted of 3 levels of potassium and 2 levels of magnesium fertilizer application to coconut palms in plots. Five years after continuation of treatment application, soil samples were taken from top soils (0-20 cm) and sub soils (20-40cm) at monthly intervals for 10 months and analyzed for exchangeable potassium and magnesium (1M ammonium acetate extraction at pH 7.0) and water soluble potassium and magnesium (1:10soil/water ratio). Leaf samples taken from the 14 frond at bimonthly intervals were analyzed for potassium and magnesiu.. The results showed that the application of potassium fertilizer decreased the quantity of both exchangeable and water extractable magnesium and magnesium fertilizer decreased the quantity of exchangeable potassium in soils. The mutual decreasing effect on the exchangeable fraction of each nutrient is attributed to low cation exchange capacity and base saturation of the soils. The close association of the coconut leaf nutrient contents with soil nutrient status implies that poor chemical characteristics of red yellow podzolic soils bring about imbalance of potassium and magnesium nutrition in coconut palms
Insect antifedents, growth regulatory and insecticidal properties of tissue culture and plant extracts of neem (Azadirachta Indica A. Juss)
No full text
Significance of non applied elements in coconut productivity
Get PDFA critical evaluation of nutritional factors involved in coconut productivity was carried out during 1991-1994. West coast tall palms aged 25 to 35 years varying in yield from 6-163 nuts per year growing in three locations. viz. Regional agricultural research station, pilicode , agricultural research station , msnnuthy and coconut research station, Balaramapuram under regular management constituted the experimental material. The relationship of individual nutrient contents in respect of 10 elements were worked out. First order nutrient ratios in respect of these elemets were also studeid. The results showed that continuous use of conventional fertilizers have lead to a stage of negative response for them. It also indicated that deficiency of non recommended and non applied elements like Mg and S and excess of Ca, Fe and Mn limits coconut yield. This points to importance of balanced nutrition for problem management and better productivity in coconut
Assessment of the effects of environmental factors on yield of coconut (Cocos nucifera L.)
Get PDFThe 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