Effect of Nutrient Management Interventions on Nutrient Uptake of Rice-zero Till Ragi under Coastal Lands

Background: The excessive usage of chemical fertilizers and the negligence on soil health regarding the conservation and use of organic sources of nutrients have not only caused the exhaustion of soil nutrient reserves but also resulted in soil health problems which is not conducive to achieving consistent increase in agricultural production. The beneficial influence of organic matter on the physical, chemical and biological properties of the soil is well known, the full appreciation of the same remains which is unfortunately ignored in modern agriculture. The regular recycling of organic wastes in the soil is the most efficient method of maintaining optimum nutrient reserves of soil and nutrient uptake by the plant. The Present Study was conducted to evaluate the nutrient status of soil under integrated usage of organic and inorganic sources. Methods: A field experiment entitled “Nutrient Management Interventions in Rice-Ragi Sequence” was conducted during kharif and rabi seasons of 2017-18 and 2018-19 on sandy loam soil of the Agricultural College Farm, Bapatla. The seven treatments consisted of T1: 100% RDF (100-60-40 kg N-P-K ha-1); T2: 100% RDF + Soil application of ZnSO4 @ 50 kg ha-1; T3: 125% RDF+Soil application of ZnSO4 @ 50 kg ha-1; T4: 75% RDF + Poultrymanure @ 0.82 t ha-1 + Soil application of ZnSO4 50 kg ha-1; T5: 75% RDF + FYM @ 5.0 t ha-1 + Soil application of ZnSO4 @ 50 kg ha-1; T6:50% RDF + Poultrymanure @ 1.6 t ha-1 + Soil application of ZnSO4 @ 50 kg ha-1 and T7: 50% RDF + FYM @ 10 t ha-1 + Soil application of ZnSO4 @ 50 kg ha-1. The experiment was laidout in randomized block design with seven treatments and replicated thrice during kharif rice and in rabi each kharif treatment was subdivided into four sub treatments (S1: Nofertilizer, S2: 100% RDF, S3:75% RDF and S4:50% RDF) and hence, The split plot design was adopted in rabi. Total No.of plots per each replication in the rabi was 28 (7x4=28). Result: Nutrient content and uptake of nitrogen, phosphorus, potassium and zinc have increased significantly with the fertility levels and organics. 50% RDF + FYM @ 10 t ha-1 + ZnSO4 @ 50 kg ha-1 recorded the highest nitrogen, phosphorus, potassium and zinc contents and uptakes in grain and straw of rice. In no till rabi ragi, N, P, K, Zn and calcium content and uptake in grain and straw were found to be significantly superior with 100% RDF (S2) to the rest of the treatments in both the years and in pooled data.