Soil Application of Silicon Enhances Initial Growth and Nitrogen Use Efficiency of Arabica Coffee Plants

Abstract

Nitrogen (N) plays a fundamental role in the initial growth of the Arabica coffee plant whereas silicon (Si) is key in enhancing performance of the plant through promoting N-use efficiency (NUE). This study evaluated the effect of N rates (0, 40, 80, and 160 mg dm−3) and Si application methods (no Si, soil-applied soluble Si, and foliar-applied soluble Si) on growth, dry matter (DM) accumulation, N and Si uptake, and NUE of young Arabica coffee plants under greenhouse conditions. Nitrogen fertilization increased the height, number of plagiotropic branches, nodes in plagiotropic branches and leaves, leaf area, root length, DM production, and N and Si uptake of the coffee plant. Results revealed that both soil and foliar application of Si increased plant height. In the presence of the highest N rates, the soil application of Si increased the number of nodes in the plagiotropic branches, length and DM of roots, and Si uptake by coffee plants. In addition, soil application of Si increased NUE indexes, an indication that it can improve performance of the young coffee plants in the field.