Influence of Biochars on Nutrient Uptake and Yield of Corn and Soybean at Two Different Landscape Positions.

Influence of biochars on nutrient uptake and yield of corn and soybean at two different landscape positions

Rajesh Chintala*,T.E. Schumacher, R.H. Gelderman, S. Sandhu, S. Kumar, D.E. Clay, D.D. Malo

Department of Plant Science, South Dakota State University,  

Brookings, South Dakota, USA

*Presenting Author: Rajesh Chintala, Department of Plant Science, SNP 247, Box 2140c, South Dakota State University, Brookings, SD, 57006. Email: rajesh.chintala@sdstate.edu

Biochar is hypothesized to change chemical and physical properties of soil and improve conditions for plant growth and crop yields.  There has been increased interest to evaluate pyrolytic biochar as a soil amendment to improve soil fertility. A field study was started in 2013 to investigate the influence of three biochars produced from carbon optimized gasification of corn stover (Zea mays L.), Ponderosa pine (Pinus ponderosa Lawson and C. Lawson) wood residue, and switchgrass (Panicum virgatum L.) on nutrient uptake and yield of corn and soybean at two landscape positions. This field study was started in 2013, all three biochars were incorporated at a 10 Mg ha^-1 rate (≈7.5 cm soil depth) with rototiller to a Maddock soil (Sandy, Mixed, Frigid Entic Hapludolls) located in an eroded upper landscape position and a Brookings soil (Fine-Silty, Mixed, Superactive, Frigid Pachic Hapludolls) located in a depositional landscape position. The experimental plot size was 4.5m x 6m with corn-soybean rotation. In 2014, two treatments including dairy manure and dairy manure + pine wood biochar were added at a depositional position of the landscape (Brookings soil). Whereas at the eroded upper landscape position (Maddock soil), three additional treatments including dairy manure, dairy manure + pine wood biochar, and the double rate corn stover biochar treatments were added in 2014. Soil, plant, and seed samples were analyzed for determination of nutrient uptake of corn and soybean crops. In 2013, there were no significant corn grain yield differences between treatments at the two landscape positions due to specific biochar treatments. Although there was an 8% greater yield on the eroded soil in the combined biochar treatments (7.8 Mg ha^-1) compared to the control (7.2 Mg ha^-1) with a 9% probability of significance. In 2014, there were again no differences in soybean seed yield on the depositional soil. On the eroded site, yields on the dairy manure, dairy manure + pine wood biochar, and the double rate corn stover biochar treatments were significantly greater than the control and the original single rate corn stover biochar treatments.  This suggests that the biochar application rate of 10 Mg ha^-1 may have been too low.  The other biochar treatments resulted in yields intermediate between the control and manure treatments.