Leaf area of Zinnia elegans Jacq. plants submitted to different sowing dates and conduction systems

Abstract

 The aim of the present paper was to study the effect of sowing dates and conduction systems on leaf area of Zinnia elegans plants and to determine regression equations to estimate leaf area when the culture was submitted to different conduction systems.  From three developmental stages: before visualization of apical flower bud, when the apical flower bud was visible and in full flowering, 45, 50 and 140 leaves were collected, respectively, for each treatment in factorial experiment. The maximum lenght (C), maximum width (L) and the real leaf area (AFR) were determined. The relation between AFR and CL was studied through linear models. It was concluded that leaf area was influenced by the sowing date at the stages before and when the apical flower bud was visible and by the sowing date and conduction system, at the full flowering stage. Although all the models obtained could be used to estimate real leaf area, it is recommended, because of its simplicity, the linear models AFR = 0.808907 Cl for the stage before visualization of apical flower bud, AFR = 0.814309 Cl for apical flower bud stage and AFR = 0.806762 CL for full lowering stage. These models could be used to estimate real leaf area for every studied sowing date and conduction system.