Effect of Potassium humate fertilizers on soil nutrients and productivity of Rice crop in vertisols of Southern India

Abstract

Humic acid is an eco-friendly product needed in lesser quantity when compared to other chemical fertilizers and manures. A field experiment was conducted for three Kharif seasons (2019, 2020 and 2021) at Regional Agricultural Research Station, Nandyala, Andhra Pradesh to study the effect of potassium humate fertilizers on soil quality and productivity of Rice crop in scarce rainfall zone of Andhra Pradesh, India. Applications of potassium humate with different doses of fertilizers showed a significant effect on selected soil characteristics. The levels of available N, P, K, and micronutrients like Fe, Zn, Cu and Mn in soil increased with different humic treatments. Significantly highest plant height, productive tillers per hill, panicle length and number of grains per panicle was observed with treatment (T4) 100% RDF + Soil application of humic acid @ 30 kg ha-1at tillering, panicle initiation and at harvest stages of crop over other treatments. Highest grain and straw yield of 6074 & 8374kg ha-1 respectively, was recorded with treatment T4 (100% RDF+30 kg ha-1Humic acid as soil application) which was on par with T2 and T3 treatments. The lowest yield was recorded with T1 (Control) 2453 kg ha-1 in all three years.