Influence of Liming on Yield of Rice and Soil Properties in Acidic Soils of High Rainfall Zone

Soil acidity is an important agricultural problem while evaluating the production potential of most of the crops. A field experiment was conducted in farmers field at Gananadhasapuram village of Thovalai taluk (strongly acidic soil) and Andarkulam village of Agastheswaram taluk (moderately acidic soil) during Pishanam (Oct-Feb) and late Pishanam (Nov–Mar) season of 2017-2018 respectively, in the high rainfall zone to study the effect of different source and levels of lime on yield of rice and soil properties. Liming materials viz., dolomite and calcite were tried at different levels along with recommended fertilizers + ZnSO 4. The experiment was conducted in RBD. The results of the experiment revealed that significantly higher grain (7.09 and 7.40 t ha-1) and straw (10.3 and 10.5 t ha-1) yield of rice were recorded with the application of dolomite @ 0.75 LR (6.36 t ha-1) (T 7) and @ 0.50 LR (1.6 t ha-1) (T 5) respectively in the strongly and moderately acidic soils along with recommended dose of fertilizers during pishanam and late pishanam seasons. The soil pH, EC, available NPK, exchangeable Ca, Mg and DTPA extractable Zn, Cu were increased and the DTPA extractable Fe and Mn were decreased upon lime application irrespective of the sources. The economics of various treatments revealed that, the highest B:C ratio (1.86 and 2.56) was recorded with the application of dolomite @ 0.75 LR (6.36 t ha 1) (T 7) and @ 0.50 LR (1.6 t ha-1) (T 5) along with recommended dose of fertilizers in the strongly and moderately acidic soils respectively during pishanam and late pishanam seasons. The study clearly indicated that in strongly acidic soils, the application of dolomite @ 0.75 LR (6.36 t ha-1) (T 7) and in moderately acidic soils, dolomite @ 0.50 LR (1.6 t ha-1) (T 5) along with recommended dose of fertilizers and ZnSO 4 is found to be the best for getting higher yield and higher returns per rupee invested under rice cultivation.