Influence of nitrogen form on the quality of Dieffenbachia amoena 'Tropic Snow'

Abstract

The plant quality in function of the ratio nitrate:ammonium has been studied The experiment was carried out in a recicling system in a Buried Solar Greenhouse. Dieffenbachia amoena 'Tropic Snow' was cultivated in expanded clay substrate. The parameters considered to evaluate the quality have been plant height, leaf area index (LAI), leaf area ratio (LAR), leaf weight ratio (LWR), biomass, shoot to root ratio, number of buds, number of leaves, leaf length and width, leaf color, variegation, and ornamental visual quality evaluated by a group of experts and consumers. The rehearsed NO3-:NH 4+ ratios has been 100:0, 50:50, and 0:100. The amoniacal form improves the following productive parameters: plant height, LAI, biomass, number of leaves, number of buds and color of the leaf, as well as the visual quality as much for experts as for consumers.