Submitted to: American Society of Agronomy Branch Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2006
Publication Date: 2/5/2007
Citation: Mulvaney, M., Balkcom, K.S., Wood, W., Meso, B., Wood, B. 2007. Effects of Tillage, Location, and Variety on Nitrogen Release From Peanut Residue Under Field Conditions. American Society of Agronomy Branch Meeting [Abstract]. Southern Branch American Society of Agronomy Annual Meetings Abstracts. 2007 CD-ROM.
Technical Abstract: An understanding of nitrogen (N) release patterns from peanut residue under field conditions will help producers make informed residue management decisions. This experiment was conducted to assess N release rates from three peanut varieties at two locations under simulated no tillage and conventional tillage systems. Three peanut varieties (NC V-11, GA-02C and Anorden) were placed in nylon mesh litterbags at two depths (surface and 10 cm deep) and two locations (Rocky Mount, NC and Headland, AL). Litterbags containing the equivalent of 4.5 Mg ha-1 were placed in a completely randomized design, blocked by location, with four replications and retrieved periodically up to 335 days after application for total N analysis on an ash-free dry weight basis. In Rocky Mount, NC, buried residue mineralized N at a higher rate than surface-placed residue. Surface and buried residue in NC released N at the rate %N = 15.7e-1.48(days) + 84.3e-0.00200(days) and %N = 38.4e-0.183(days) + 61.6e-0.00101(days), respectively. Additionally, the Virginia type variety (NC V-11) mineralized N at a higher rate than the two runner type varieties (GA-02C and Anorden) tested in NC. All treatments released N at the same rate in Headland, Alabama. Nitrogen is mineralized quickly from peanut residue. In NC, the higher N mineralization rate of buried residue is likely due to greater soil microbial activity acting on the residue. Although there was no difference between initial C:N ratios among any of the varieties, the faster rate of N mineralization exhibited by NC V-11 at NC may be due to different lignin and carbohydrate levels compared to the other two varieties. Warmer and moister climatic conditions in AL are likely responsible for the lack of treatment differences at this location.