Influence of paclobutrazol application on the flower size and yield of China aster (Callistephus chinensis (L.) Nees)

Abstract: The effects of method of application and concentration of paclobutrazol on flower stalk length, flower size, flower longevity and yield of China aster were studied. Thiry five days old seedlings of China aster cv. Poornima were treated with paclobutrazol @ 0, 25, 50, 100 and 200 ppm through root dip, soil drench and foliar spray methods. Length of flower stalk and flower size significantly decreased with increased concentrations of paclobutrazol except in case of flower size when applied as foliar spray. Contrarily, flower longevity not influenced adversely with increased concentration of paclobutrazol, whether applied as root dip or soil drench or foliar spray. In each application method, flower yield was significantly higher at 25 ppm paclobutrazol. However, drench application of paclobutrazol was consistently more effective than foliar or root dip treatments with regard to length of flower stalk. Among the different levels and methods of paclobutrazol application, plants treated with 25 ppm as foliar spray proved to be superior over control and rest of the treatment combinations by increasing flower diameter and yield of cut flower as compared to control.