Distribution of nitrogen, phosphorus, potassium and zinc content in mango grown acidic soils of Jharkhand

Abstract

The mango orchards grown in acidic soils of Jharkhand were evaluated for pH, organic carbon (OC), available macro- (N, P and K) and DTPA-micronutrient (Zn) content in the soil profile. Soil samples were collected from 27 different mango orchards comprised of three health levels (unhealthy, medium and healthy) and three age groups (1-3 year, 4-5 year and 6-7 year). The pH of the surface soil was low and gradually increased with increase in depth of soil profile. The pH was lowest in unhealthy (4.96) as well as in 1-3 year old orchard (4.72). The organic carbon content was highest of 5.40 and 5.57 g kg-1 in healthy and 6-7 year old orchard, respectively in 0-30cm depth. The available nitrogen content varied from 67.2-139.4 kg ha-1 among the health levels of orchard. Among the age levels of orchard, the available nitrogen content varied from 82.8-128.2 kg ha-1. The available phosphorus content varied from 1.8-7.3 and 0.8-5.7 kg ha-1 among health levels and age levels of orchard, respectively. The exchangeable potassium content was highest of 309.5 and 334.3 kg ha-1 in healthy and 6-7 year old orchards, respectively in 0-30cm depth. The DTPA-extractable Zn content varied from 0.27-0.48 and 0.24-0.40 mg kg-1 among health levels and age levels of orchard, respectively. The soils of different orchards were low in organic carbon, available nitrogen and available phosphorus; sufficiency in exchangeable K and DTPA-extractable zinc was critically low.