Effect of soil application of organic nano NPK formulation on growth and yield sesame Sesamum indicum in Onattukara AEU 3

Abstract

The study entitled “Effect of soil application of organic nano NPK formulation on growth and yield of sesame (Sesamum indicum) in Onattukara (AEU 3)” was conducted at ORARS, Kayamkulam and College of Agriculture, Vellayani, during December 2020 to April 2021. This investigation aimed to characterize the organic nano NPK formulation, to assess the nutrient release pattern under laboratory conditions and to study the effect of soil application of organic nano NPK formulation on crop growth, yield, quality and soil health using sesame as a test crop in Onattukara (AEU 3). ‘TAG NANO NPK’ is the commercial formulation of organic nano NPK used in this study. The experiment consisted of three parts. Characterization of organic nano NPK formulation was the first part of this investigation. The particle size of organic nano NPK formulation confirmed the nanoscale dimension (70.44 nm) with higher surface area (140.31 m2 g -1 ) and stable zeta potential (-64.10 mV). The organic nano NPK recorded a basic pH (7.81) with an electrical conductivity of 0.13 dS m-1 . The presence of major nutrients (1.96 % N, 1.81% P, 2.96 % K, 0.32% Ca, 0.29% Mg and 0.61 % S), micronutrients (398 mg kg-1 Fe, 528 mg kg-1 Mn, 352 mg kg-1 Zn, 98.86 mg kg-1 Cu and 33.40 mg kg-1 B), organic carbon (2.34 %), organic matter fractions (5.80 % humin, 19.18% humic acid and 31.54 % fulvic acid) and amino acids (248 mg kg-1 ) were determined. The second part was the laboratory incubation study to assess the nutrient release pattern. The design of the experiment was CRD with 9 treatments and 3 replications. The treatments applied were soil application of organic nano NPK formulation 25 kg ha-1 (T1), organic nano NPK formulation 25 kg ha-1 + FYM 5 t ha-1 (T2), organic nano NPK formulation 25 kg ha-1 + 50 per cent of recommended dose of NPK (T3), organic nano NPK formulation 25 kg ha-1 + FYM 5 t ha-1 + 50 per cent of recommended dose of NPK (T4), organic nano NPK formulation 50 kg ha-1 (T5), organic nano NPK formulation 50 kg ha-1 + FYM 5 t ha-1 (T6), organic nano NPK formulation 50 kg ha-1 + 50 per cent of recommended dose of NPK (T7), organic nano NPK formulation 50 kg ha-1 + FYM 5 t ha-1 +50 per cent of recommended dose of NPK (T8) and absolute control (T9). The pH and organic carbon content of the soil increased throughout the incubation study, whereas the electrical conductivity of the soil declined after 30 days of incubation. In general, major and micronutrient availability was increased upto 45th day of incubation except for Mg, S and Fe whose availability was reduced after 30th day of incubation. The treatment T8 (organic nano NPK 50 kg ha-1+ FYM 5 t ha-1 + 50 per cent recommended dose of NPK) showed highest availability of major nutrients except N and Mg, which were more available in treatment T6 (Organic nano NPK 50 kg ha-1 and FYM 5 t ha-1 ). Among micronutrients, Fe and Zn availability was recorded highest in treatment T6 (organic nano NPK 50 kg ha-1 and FYM 5 t ha-1 ). The combined application of organic nano NPK, FYM and 50 per cent recommended dose of NPK resulted in higher Mn (T8), Cu (T8) and B (T4) availability. The third part of the experiment was the field study. It was designed as randomized blocks with 10 treatments replicated thrice. The treatments consisted of 2 levels of organic nano NPK (25 kg ha-1 and 50 kg ha-1 ) with FYM (T2 and T6) and without FYM (T1 and T5) and combination of organic nano NPK (25 kg ha-1 and 50 kg ha-1 ) and 50 per cent recommended dose of NPK with FYM (T4 and T8) or without FYM (T3 and T7) along with soil test based recommendation of NPK and FYM (T9) and absolute control (T10). The growth and yield parameters of sesame viz., plant height, height upto first capsule, primary branches per plant, leaf area per plant, root spread, root volume, number of capsules per plant, number of seeds per capsule, thousand seed weight, seed yield and bhusa yield were significantly influenced by the application of organic nano NPK. Application of organic nano NPK 50 kg ha-1 and FYM 5 t ha-1 (T6) resulted in 42 per cent yield increase compared to absolute control. Oil content and grain protein content were also enhanced by the organic nano NPK application. Uptake of major nutrients and micronutrients were higher in treatment T6(organic nano NPK 50 kg ha-1 and FYM 5 t ha-1 ), whereas combined application of organic nano NPK, FYM and 50 per cent recommended dose of NPK resulted in higher N (T4), Ca (T8) and S (T8) uptake. The soil was analysed after the crop harvest to determine the physical, chemical and biochemical properties of the soil and recorded a significant influence of organic nano NPK in these parameters. The organic nano NPK showed a higher B:C ratio (1.99) against the control plot (1.67). From the characterization study, it was obvious that the organic nano NPK (TAG NANO NPK) had a particle size in nano scale range (70.44 nm) and possessed higher surface area (140.31 m2 g -1 ). It is a complete nutritional organic fertilizer which contains major nutrients, micronutrients, amino acids and humic substances. The incubation study concluded that the nutrient release in organic nano NPK was slower and longer. Nutrient availability was increased upto 45th day of incubation. From the field study, it was evident that the combined soil application of organic nano NPK 50 kg ha-1 and FYM 5 t ha-1 as basal dose improved the physical, chemical and biochemical properties of the soil and enhanced growth, yield and quality of sesame in Onattukara. From this experiment, it was concluded that the soil application of organic nano NPK in the form ‘TAG NANO NPK’ 50 kg ha-1 and FYM 5 t ha-1 can be an economically and environmentally sustainable substitute for chemical fertilizers in sesame grown in the constrained loamy sand soils of Onattukara.