Influence of humic substance and phosphorus fertilizers on nutrient assimilation by aerobic rice in acid soil Sagar R.*, Thippeshappa G.N., Kadalli G.G.1, Ganapathi, Gurumurhty K.T., Nandish M.S.2, Kumar M. Dinesh3 Department of Soil Science and Agricultural Chemistry, University of Agricultural and Horticultural Sciences, Shivamogga, 577204, Karnataka, India 1Department of Soil Science and Agricultural Chemistry, University of Agricultural Sciences, Bengaluru, 560065, Karnataka, India 2Department of Agricultural Microbiology, University of Agricultural and Horticultural Sciences, Shivamogga, 577204, Karnataka, India 3Department of Agronomy, University of Agricultural and Horticultural Sciences, Shivamogga, 577204, Karnataka, India *Corresponding author (Email: sagarramaiah@gmail.com)
Online published on 1 March, 2024. Abstract The study was conducted in Agricultural and Horticultural Research Station, Tarikere taluk, Karnataka, India and the objective was to ascertain the effects of humic substance on aerobic rice's capacity to assimilate nutrients when used in combination with various phosphorus (P) fertilizers of variable solubilities and planted in acidic soil. The humic substance used for treatment application was extracted from well decomposed farmyard manure (FYM). The treatment getting rock phosphate (RP) in combination with humic substance @ 75 L ha−1 was found to have a significantly greater nutritional content in grain and straw of aerobic rice than rest of the treatments, except for sulphur (S), which was significantly higher in T7 treatment having single superphosphate (SSP) and humic substance @ 75 L ha−1. In turn, the treatment with the application of RP along with humic substance @ 75 L ha−1 showed a significantly higher uptake of primary, secondary and micronutrients by grain and straw of aerobic rice over all other treatments and it was followed by RP + humic substance @ 50 L ha−1 treatment compared to P fertilizers without humic substance treatments. With an increase in humic substance levels, aerobic rice was able to absorb more of nutrients. The study clearly demonstrated that crop nutrient demand in acid soils could be met with the use of humic substance. Top Keywords Nutrient uptake, Humic substance, FYM, Aerobic rice, Acid soil. Top |