White clover living mulch controlled only by mowing supplies nitrogen to corn

Abstract

A field experiment was conducted to investigate the effects of white clover (Trifolium repens L.) living mulch controlled only by mowing on the nitrogen (N) nutrition and yield of silage corn (Zea mays L.). Eight treatments were tested: one living mulch treatment without N application and seven conventional cultivation treatments with different N applications (0–200 kg ha−1). White clover was sown in the living mulch treatment in August. The next May, white clover shoots in the living mulch treatment were clipped and left in the field. After tilling the conventional cultivation treatments, corn was sown. At the time when the corn was sown, the N uptake of the white clover shoots was 173 kg ha−1. Measurements at 40 days after the sowing of corn (40 DAS) revealed that the N concentration of corn shoots grown in the living mulch treatment was lower than that in the conventional cultivation treatment without N application. At harvest (123 DAS), compared with that in the conventional cultivation treatment without N application, the N uptake of corn shoots in the living mulch treatment increased by 31.8 kg ha−1. Based on the N uptake and the yield of corn, the fertilizer N equivalencies of living mulch were 62 and 70 kg ha−1 at harvest, respectively. These results indicate that living mulch controlled only by mowing increases the N uptake of corn and may reduce the N application required for corn production.