Crop response to biochar under differing irrigation levels in the southeastern USA

Application of biochar to soils is hypothesized to increase crop yield. Crop productivity impacts of biochar application in southeastern cropping systems consisting of peanut (Arachis hypogaea L.), corn (Zea mays L.), and cotton (Gossypium hirsutum L.) produced under varying rates of irrigation have not been addressed. This research incorporated biochar at two different rates into a long-term irrigation and cropping systems study to compare yield and quality response of peanut, corn, and cotton. Biochar was incorporated into soil once at the beginning of the 4-year project at rates of 22.4 and 44.8 Mg ha^?1. Peanut, corn, and cotton were produced under three sprinkler irrigation levels (100%, 66%, and 33%), shallow surface drip irrigation (100%), and a nonirrigated control. Crop input management followed best management practices. Sprinkler irrigation was scheduled by Irrigator Pro for Peanuts, Corn, and Cotton at the 100% level and the 66% and 33% levels were applied at the same time as the 100% level. Significant year, irrigation, and year × irrigation effects for corn, cotton, and peanut yield resulted (p < 0.001). No differences resulted for biochar in corn (p = 0.930) or cotton (p = 0.678). Peanut yield showed a significant response to biochar comparing the 44.8 Mg ha^?1 rate to the untreated control in nonirrigated production at the p = 0.05 level and in the 33% irrigated treatment at the p = 0.10 level. No negative effects resulted from biochar opening opportunities for biochar application in southeastern U.S. cropping systems for purposes related to carbon sequestration without compromising productivity of producers and related agricultural sectors.