EFFECT OF FOLIAR APPLICATION OF NITROGEN WITH OR WITHOUT GROWTH REGULATORS ON DEADLY NIGHTSHADE (ATROPA BELLADONNA L.) PART I: GROWTH AND DRY BIOMASS

Abstract

The aim of ongoing investigation was to study the effects of nitrogen with or without some growth regulators such as benzyl amino purine (BAP) or gibberillic acid (GA3) on growth and dry biomass of deadly nightshade (Atropa belladonna). This investigation was carried out in Department of Horticulture and Landscape Gardening, College of Agriculture, University of Baghdad, Iraq during the growing season 2008/2009 in a factorial experiment in randomized complete block design with three replications. The experiment was designed to study the effect of foliar application of nitrogen with or without growth regulators of gibberellic acid on plant growth and dry biomass accumulation. It was found that foliar application of nitrogen significantly increased the length of main stem and plant height. The highest number of branches per plant and dry weight of the roots were recorded. Application of 2000 mg N L-1 resulted in the highest number of leaves on the main stem, leaf area per plant and dry weight of the aerial parts. Nitrogen application did not affect SPAD unit significantly. Application of was found to increase the number of branches, leaf area per plant, number of leaves on the main stem and dry weight of the aerial parts while GA3 increased the length and diameter of the main stem, the height of the plant and the dry weight of aerial parts and roots significantly. A conclusion can be made that application of nitrogen at 2,000 mg L-1 plus benzyl amino purine at 50 mg L-1 is the recommended treatment.