Mesure du taux de couverture du sol pour estimer les principales caractéristiques d’une culture de colza avant montaison

Abstract

Leaf area index (LAI), crop dry matter (DM) and nitrogen amount in the canopy (N) are amongst the main parameters characterizing rapeseed crop before the onset of stem elongation. The correlations of these parameters with the ground cover ratio estimated from vertical-l view photographs taken at a heigth of 1.5 m, allow a fairly good indirect estimate of LAI, and satisfactory estimates of DM and N, when practical constraints make difficult their direct measurement. © John Libbey Eurotext 2000.