Short-term Response of Chickpea Yield, Total Soil Carbon, and Soil Nitrogen to Different Tillage and Organic Amendment Regimes

ABSTRACT

A 2-year study evaluated the effects of chemical nitrogen fertilizer and organic fertilizer under conventional and reduced tillage. Tillage systems were subplots, and composted cattle manure (25 tons ha⁻¹, CCM), nitrogen fertilizer (N; 40 kg N ha⁻¹), CCM+N (12.5 tons CCM+20 kg N ha⁻¹), and no urea N or manure added control (CONT) were sub-subplots. Highest yield, 1000-seed weight, fruit length, and plant height occurred in CCM+N, but were not significantly different from those using just N. Increase in yield for CCM, CCM+N, and N treated plots compared to CONT were 28%, 46%, and 40%, respectively. Plots treated with CCM or CCM+N contained greater soil organic carbon (SOC) than plots treated with N or CONT. SOC was significantly higher in reduced tillage compared with conventional tillage. Highest total soil nitrogen and seed N content were observed in plots receiving CCM+N, followed by N, and CCM. The combined application of 12.5 ton CCM and 20 kg N ha⁻¹ N fertilizer produced acceptable yields while reducing environmental impact. Reduced tillage did not affect yield, but positively affected SOC. Thus, both systems have potential as alternative strategies because both can improve the highly diminished soils of southern Iran.

KEYWORDS:

• Composted cattle manure
• nitrogen
• reduced tillage