Root Development of Leek in a Cropping System With Red Clover

ABSTRACT

This root study was part of a field experiment where the aim was to assess the possibilities of synchronizing N mineralization from red clover (Trifolium pratense L. cv. Vivi) with N uptake in leek (Allium porrum L. cv. Hilari). Strips of red clover, left between the rows of leek, were incorporated either at planting or 2 or 4 weeks after planting. The objectives in the part of the experiment presented in this article were to evaluate how leek root growth was influenced by row distance, time of incorporation and red clover. Due to slow lateral root proliferation, the N uptake between rows in the clover treatment with 0.7 m row distance was lower than in the treatment with 0.5 m row distance. As a result, higher amounts of mineral N were left between rows in the former treatment where it constituted a risk of N leaching after crop harvest. Neither row distances nor time of incorporation influenced root weight. In the 0–0.15 m soil layer root intensity was higher and lateral distribution more even in the control treatment than in the clover treatment.