Effect of long-term application of farmyard manure on soil micronutrient status

Abstract

In a long-term experiment conducted (1967 – 2001) at Hisar, India, pearl millet (Pennisetum typhoides) and wheat (Triticum aestivum) was grown during summer and winter in a rotation. The treatments consisted of farmyard manure (FYM) at the rate of 15, 30 and 45 Mg ha − 1 during one or both the seasons. A treatment without FYM was maintained as a control. This made the total number of treatments 10, along with 2 levels of nitrogen at 0 and 120 kg ha − 1. Samples from 0 – 15, 15 – 30 and 30 – 45 cm soil depths were collected and analysed for DTPA extractable and total content of zinc, iron, manganese and copper. Application of FYM significantly increased the DTPA extractable and total content of all the studied micronutrients in all soil depths. The increase was higher in the surface layer than in the lower depths. The time of application of FYM influenced the content of soil micronutrients. DTPA extractable and total content of micronutrients was higher when FYM was applied in winter as compared to summer. Application of N has no effect on DTPA extractable or total micronutrients content.