Impact of soil fertility characteristics on artificial fertility gradient approach developed using sorghum (Sorghum bicolor) in Alfisols

Abstract

In the advent of precision agriculture, applying fertilizer based on soil testing is a crucial tool to prescribe nutrient levels for crops, to increase nutrient use efficiency and production. A field experiment was conducted in a farmer's field in the Dindigul district, Southern agro-climatic zone of Tamil Nadu to ascertain the effect of artificial soil fertility gradient method on soil fertility, green fodder production of sorghum (Sorghum bicolor (L.) Moench) (var. CO 30) and nutrient absorption. A fertility gradient technique has been investigated to produce fertilizer recommendations for location-specific in red soils (Alfisols, Typic Rho-dustalf). The experimental field was separated into three equal strips: strip I, II, and III, which received applications of the three graded levels of ertilizer N0P0K0, N1P1K1, and N2P2K2, respectively. Urea, single super phosphate, and muriate of potash fertiliz-ers, respectively, were used to apply NPK. As a gradient crop, S. bicolor was raised. The N1 level was set based on the general fertilizer recommendation of feed sorghum, while the P1 and K1 values were set based on the soil’s ability to fix 100 kg ha-1 of phosphorus and 100 kg ha-1 of potassium, respectively. Plant samples were taken at harvest time, and their NPK content and nutrient uptake were determined. With addition of graded doses of nitrogen, phosphorus and potassium fertilizer in Strip I, II & III increased the soil's available N, P & K status substantially in the order of Strip I