Status of Micronutrients in Rice Growing Alluvial Soils of Delta Area of Krishna District, Andhra Pradesh, India

Abstract

An investigation was carried out to study the micronutrient status of rice-growing soils of the delta area of Krishna district in Andhra Pradesh to know the potential of these soils to supply micronutrients to rice crops. For this, six profiles viz., Vemulamada (P1), Kothapalli (P2), Velivelu (P3), Nangegadda (P4), Penamaluru (P5), and Ganguru (P6) were studied covering the major cereal-maize/ cereal- pulse growing areas. The soils were near neutral to strongly alkaline in reaction, non-saline, and low in organic carbon content.  The weighted average of DTPA extractable zinc, copper, iron, and manganese ranged from 0.71 mg kg-1 (P6) – 1.65 mg kg-1 (P2), 1.50 mg kg-1 (P2) – 3.38 mg kg-1 (P3), 4.35 mg kg-1 (P1)- 5.62 mg kg-1 (P5) and 5.6 mg kg-1 (P4) to 11.95 mg kg-1 (P6) respectively. A mixed trend is observed across horizons in all profiles. DTPA-Fe exhibited low variability while the other micronutrients displayed higher variability. The DTPA extractable Zn was found to be deficient whereas DTPA extractable Cu and Mn were found to be sufficient. The available Mn was decreased with increasing depth in most of the profiles. All the micronutrient are positive correlation with organic carbon content.