IMPROVING GROWTH QUALITY OF Pelargonium zonale, L. BY USING SOME GROWTH RETARDANTS.

Abstract

This study was conducted in the nursery of Baramoon Research Station, Horticulture Research Institute, Agriculture Research Center, during two successive seasons ( 2004/2005 and 2005/2006), aiming to investigate the effect of different concentrations of Cycocel (CCC) at 1500 and 3000 and Paclobutrazol (PBZ) at 75 and 150 ppm on Pelargonium zonale, L. (Red cultivar) plants. Foliar spray was once (after 15 days) or twice (after 15 and 30 days from planting). The most important results can be summarized as follows:-1-CCC and PBZ controlled plant height in all treated plants and induced profuse branching. 2-The used growth retardants induced plentiful inflorescences as compared with control plants. 3-All of PBZ and most of CCC treatments reduced number of days to flower. 4-All CCC or PBZ treatments increased the total chlorophyll and carbohydrates content.For obtaining compact plants, earlier flowering with dark green leaves, a profuse branches and plentiful inflorescences it may be recommended to use PBZ at 75 ppm twice.