Row and Forage Crop Rotation Effects on Maize Mineral Nutrition and Yield.

Diverse crop rotations are an integral component of sustainable agriculture. The objectives were to investigate row and forage crop rotation effects on stover biomass, grain yield, and mineral nutrient concentrations of maize (Zea mays L.) grown under maize-soybean [Glycine max (L.) Merr.] 2-yr rotation (C-S); maize-soybean-spring wheat (Triticum aestivum L.) 3-yr rotation (C-S-W); maize-soybean-oat/pea (Hordeum vulgare L./Pisum sativum L.) hay 3-yr rotation (C-S-H); and maize-soybean-oat/pea hay underseeded with alfalfa (Medicago sativa L.)-alfalfa-alfalfa 5-yr rotation (C-S-H/A-A-A). Rotations were established in 1997 and maize plots were sampled in 2008 through 2011. Across the four years of the study, grain yield was 10% greater (1.0 Mg ha^-1) in C-S-H/A-A-A and C-S-W rotations compared to C-S with C-S-H intermediate. Under C-S-H/A-A-A, kernel N concentration was 7% greater, kernel P 17% less, and kernel K 7% less compared to C-S-W. Kernel Zn concentration was 16% lower in C-S-H than C-S and C-S-H/A-A-A. Thus, diversification of the C-S rotation with wheat (C-S-W) increased yield while conserving kernel P and K concentration whereas diversification with oat/pea hay plus alfalfa (C-S-H/A-A-A) increased grain yield and kernel N concentration but decreased both kernel P and kernel K concentration.