Effects of long-term application of different modes and levels of farmyard manure and fertilizer nitrogen on soil properties and wheat grain yield

A long term field experiment started in 1967 was selected to study the impact of modes, levels of farmyard manure (FYM) and fertilizer N application on soil properties and wheat grain yield. After 50 years of cropping, significant decrease in soil pH was recorded with application of FYM during (kharif and rabi) mode (7.56) and, rabi mode (7.71) as compared to kharif mode applications. However, soil EC showed the reverse trends. Modes of FYM application showed significant impact to accure SOC and highest SOC (1.66%) was recorded under both seasons application followed by rabi (1.49%) or kharif (1.41%) season. Addition of 15 t ha^-1 FYM showed superiority over lower doses as far as soil health was concerned and resulted in higher values of SOC (1.67%). Application of FYM @ 15 t ha^-1 caused significant increase in nutrient availability: available N (256.70 kg ha^-1), P (103.03 kg ha^-1) as compared to application of FYM@10 or 5 t ha^-1. With the application of FYM @15, 10 and 5 t ha^-1, the increase in grain yield of wheat was 56.69, 51.27 and 40.13% over control, respectively. Application of fertilizer N significantly increased SOC (5.76%), available N (5.99%), P (6.59%), and wheat grain yield (26.72 %) as compared to plots receiving FYM only. Interactions of mode and level of FYM applications was found significant and enhanced P availability and accreted SOC. Therefore, it is suggested that combined use of FYM@15 t ha^-1 coupled with fertilizer N @120 kg ha^-1 during both the season could be beneficial for enhancing long-term nutrient availability and crop productivity under pearl millet-wheat cropping system of semi arid eco-region of Haryana.