1. Department of Plant Nutrition, China Agricultural University, Key Laboratory of Plant-Soil Interactions, Beijing 100193, People’s Republic of China (L.C., J.S.); Department of Agronomy and Plant Genetics (L.C., B.B., C.P.V.) and Department of Soil, Water, and Climate (D.A.), University of Minnesota, St. Paul, Minnesota 55108; United States Department of Agriculture Agricultural Research Service,