Vol. 11, Issue 5 (2022)

Author(s):
YS Satish Kumar, CH Sujani Rao, PRK Prasad, K Jaya Lalitha, S Jaffar Basha and T Venkata Sridhar

Abstract:
Humic acid is an eco-friendly product needed in lesser quantity when compared to other chemical fertilizers and manures. Humic Acid can be integrated into the soils in the form of manure; it improves the physical properties of the soil. A field experiment was conducted at the College Farm, Agricultural College, Mahanandi, ANGRAU during kharif & rabi seasons of 2020-21 and 2021-22. The experimental soil was sandy loam in texture with 7.52 pH, 0.42 dsm-1 EC, 0.32 % OC, low available N (175 kg ha^-1), medium in P (18.48 kg ha^-1), high in K (580 kg ha^-1) and sufficient in Zn status (0.85 ppm). The experiment was laid out in Split plot design with three replications with four main plots and six sub plots total twenty four treatments. The study revealed that N,P & K uptake in Foxtail millet at harvesting stage in grain & straw, by application of different humic acid treatments significantly influenced the plant nitrogen uptake at all the stages of crop growth. There is a significant increase in nitrogen uptake in treatments which received humic acid dose @ 20 Kg/ha along with 0.2% foliar spray of humic acid. In main plots, Highest Nitrogen uptake was recorded in treatment M4 (4.64, 6.32 kg ha^-1 in 2020 and 5.42 & 7.39 kg ha^-1 in 2021) which received 100% RDF through inorganics in kharif season recorded significantly higher nitrogen uptake at harvest stages (Grain and Straw) and it was on par with the treatment M3 i.e., 75% RDF through inorganics (4.27, 5.74 kg ha^-1 in 2020 and 4.98, 6.71 kg ha^-1 in 2021). Among the sub plots, the treatment S6 which received 20 Kg humic acid per hectare recorded higher N uptake (4.51, 6.00 kg ha^-1 in 2020 and 4.92,7.12 kg ha^-1 in 2021) at harvesting stage (Grain and Straw) respectively in foxtail millet which was on par with treatment S3. The interaction effects between main plots and sub plots was non significant. Similar results were reported in P & K uptake studies too. This might be due to higher availability of plant nutrients with fertilization, which resulted in enhanced nutrient uptake in plant tissues and more biomass production at higher total fertilizer application.