Effect of dolomite and calcite on growth, yield and economics of rice in strongly acidic soils of Kanyakumari district

Abstract

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, Kanyakumari district during Pishanam (Oct-Feb) season of 2017-2018. To utilize the calcite and dolomite in different levels along with RDF + ZnSO₄ with ten treatments based on Lime requirement and replicated thrice in RBD design. The results revealed that significantly highest plant height (100 cm), number of tillers m^-2 (411), number of productive tillers m^-2 (375), thousand grain weight (26.6 g), grain (7.09 t ha^-1) and straw (10.3 t ha^-1) yield of rice were recorded with the application of dolomite @ 0.75 LR (6.36 t ha^-1) along with RDF + ZnSO₄ (T₇) compared to other treatments. The economic analysis demonstrates that dolomite @ 0.75 LR (6.36 t ha^-1) along with RDF + ZnSO₄ treatment produced higher gross returns (INR 116662 ha^-1), net returns (INR 54018 ha^-1) and B: C (1.86) ratio than all other treatments. The study clearly indicated that in strongly acidic soils, the treatment T₇ is found to be the best for getting higher yield and higher returns per rupee invested under rice cultivation during Pishanam season.