Effects of Topdressing Frequency on Growth and Yield of Maize in Aeolian Sandy Soil under Fertigation

【Objective】 Fertilizer topdressing is an agricultural practice to provide crops with additional nutrients, but how topdressing frequency affects crop growth and yield is inadequately understood. The objective of this paper is to determine the optimal nitrogen topdressing frequency for improving maize cultivation in aeolian sandy soil. 【Method】 The experiment was conducted in a maize field with nitrogen fertilizer applied in one (F1), two (F2), four (F3), seven (F4) and eleven (F5) topdressings. For each treatment, we measured the growth and grain yield of the maize. 【Result】 Topdressing once at the jointing stage or before the earing stage increased vegetative growth, stem length and diameter, leaf area index, and SPAD content. In contrast, multiple topdressing improved spike length and diameter, kernel numbers per spike, and 100-seed weights, ultimately leading to an elevated yield. The grain yield depended not only on topdressing frequency but also on when and how the fertilizer was applied in each topdress