2.2. Field experiment and cultural practices
A field experiment with two (2) types of tillage (conventional tillage, CT and No-till, NT) and three (3) crop rotations (continuous corn, CC; corn–soybean, CS; and corn–soybean–wheat, CSW) in factorial arrangement of randomized complete block (RCB) design was established in 2002. Each treatment was replicated 3 times on 40 × 100 m2 plots.