Influence of Organic Nutrient Sources and Inorganic Fertility Levels on Nutrient Uptake of Aerobic Rice (Oryza sativa L.) during Kharif Season

A field study was taken up to evaluate the influence of organic sources of nutrients and inorganic fertility levels in aerobic rice during kharif 2017 and kharif 2018 at Indian Institute of Rice Research, Rajendra Nagar, Hyderabad, Telangana. The experiment was laid out in split plot design with three replications. The treatment comprised of M1: Neem leaf manure 6 t ha-1; M2: Vermicompost 2 t ha-1; M3: Goat manure 5 t ha-1; M4: Microbial consortia [seed treatment 4g kg-1 + soil application 4 kg ha-1]. The sub-plot treatments comprised of S1: Control; S2: 50 % RDF; S3: 75 % RDF; S4: 100 % RDF [Recommended Dose of Fertilizer 120:60:40 kg ha-1]. It was observed that, nutrient uptake by aerobic rice was significantly influenced with application of organic nutrient sources and inorganic nutrient levels. N, P and K uptakes by rice were higher with vermicompost @ 2 t ha-1 or goat manure @ 5 t ha-1 among organic sources and 100% RDF among nutrient levels. Vermicompost recorded significantly highest nitrogen (55.76, 71.7, 91.6 and 103.5 kg ha-1 respectively), phosphorus (9.04, 15.4, 18.0 and 20.5 kg ha-1) and potassium (39.7, 60.0, 76.3, 107.1 kg ha-1) uptake by rice crop at MT, PI, 50% FL and harvest and it was found at par with goat manure ( viz; nitrogen : 50.79, 66.1, 85.6 and 97.7 kg ha-1 ; phosphorus : 8.33, 14.11, 16.4 and 19.2 kg ha-1 and potassium : 38.2, 59.5, 75.2 and 84.0 kg ha-1 at MT, PI, 50% FL and harvest ) while the lowest nutrient uptake (viz; nitrogen: 37.86, 46.1, 60.9 and 77.3 kg ha-1, phosphorus: 5.74, 8.59, 11.4 and 12.6 kg ha-1 and potassium: 25.8, 41.3, 48.6 and 71.5 kg ha-1) was found with application neem leaf manure. Application of 100% RDF significantly increased N (63.58, 80.0, 99.1 and 123.1 kg ha-1), P (9.90, 17.1, 19.9 and 24.3 kg ha-1) and K (47.3, 70.8, 88.9 and 119.5 kg ha-1) and the lowest N (26.37, 32.5, 45.6 and 47.0 kg ha-1), P (4.11, 6.12, 7.7 & 7.8 kg ha-1) and K (19.3, 28.3, 34.7 and 56.7 kg ha-1) was recorded with control. Conjunctive use of 75% of RDF along with vermicompost (M2S3) or goat manure (M3S3) resulted in statistically on par nitrogen and phosphorus uptake with that of 100% RDF and the lowest nitrogen and phosphorus uptake were recorded with combination of either neem leaf manure or microbial consortia and no application of fertilizer (M1S1 and M4S1, respectively).