EFFECTS OF PLANT GROWTH RETARDANTS ON DEVELOPMENT OF POINSETTIA ”CHRISTMAS FEELING” CULTIVAR

Artúr Botond CSORBA 1,2, Mária TATÁR 1, Erzsébet BUTA 3, Katalin MOLNÁR 1, Erzsébet DOMOKOS 1, Attila BANDI 1, János BÁLINT 1*
1 Department of Horticulture, Faculty of Technical and Human Sciences, Sapientia-Hungarian University of Transylvania, Tg. Mureş
2 Doctoral School in Biology and Sport Biology, University of Pécs, Faculty of Sciences, Ifjúság útja 6.
3 University of Agricultural Sciences and Veterinary Medicine, Faculty of Horticulture, 3-5 Mănăștur Str., 400372, Cluj-Napoca

The poinsettias were cultivated years ago as medicinal and ornamental plants, too; but in the recent time are in the light of world flower assortment surprising with new shapes and colors in the cold season. The ornamental values of these plants are given by bracts which can have the same size as foliage leaves or even larger. The tendency of floral industry consists in obtaining high quality ornamental plants with superior marketable price. In these regards, the role of plant growth retardants in regulating the growth of poinsettia is important to obtain healthy, compact bushes and extended decoration period. The aim of the paper is to evaluate the effects of plant growth retardants on poinsettia. Five treatments with different retardants were applied as drench or spray. In the experiment four replicates and a total of 144 poinsettias were used. Treatments with paclobutrazol (60 mg/l sprayed), daminozide (2500 mg/l sprayed) and chlormequat chloride (1000 mg/l sprayed), showed the best results in case of marketability.