디니코나졸 처리가 포트멈의 생육 및 개화에 미치는 영향 Mi-Kyoung Won 1, Byung-Joo Lee, 2, Euy-Seog Yang 1, Won-Chun Choi 1 1 Yesan Chrysanthemum Experiment Station, Chungnam Provincial ARES, Yesan , Korea 2 Chungnam Provincial ARES, Yesan , Korea,  Potted chrysanthemums are treated with growth retardants to control plant height in good production to the container size.  Daminozide has been most commonly used for growth retardation because it is easy to use and plant response is predictable.  Some triazole fungicides in which diniconazole belongs, were effective for growth inhibition in chinese cabbage, ‘ New Guinea ’ Impatiens, lily and so on.  The aim of this study was to investigate the effects of diniconzaole treatment on the growth and flowering in potted chrysanthemum cv. New Orleans. Effects of Diniconazole on Growth and Flowering in Potted Chrysanthemum ‘ New Orleans ’ MATERIALS AND METHODS RESULTS AND DISCUSSION INTRODUCTION  ‘New Orleans’ Chrysanthemum rooted cuttings were planted one per 11cm pot filled with Mix 2(Sungro Co.), and pinched 2 weeks after planting.  Short day treatment started 1 week after pinching, and continued until flower bud color was visible.  To investigate the proper spray concentration of diniconazole, 4 treatments(25, 50, 100, 200 mg  L -1 ) were given 2 times(1 week and 4 week after pinching). The growth retardant used for comparison was daminozide at 2,500 mg  L -1. Control plants were sprayed with water.  This experimental design was completely randomized block with 3 replications and 5 pots per replication. All data were subjected to analysis of variance using SAS.  Plant height was reduced with increasing diniconazole concentration at 25, 50, 100, 200 mg  L -1 up to 19.3%, 26.7%, 29.8%, 30.5 % respectively (Fig. 1).  The number of leaves and the leaf area per plant were decreased at all treatments of diniconazole. The content of chlorophyll increased at all treatments of diniconazole and stem diameter tended to be increased at the highest concentration of diniconazole.  All chemical treatments slightly delayed days to flowering by 2-4 days compared with control. Flower number was reduced with all chemical treatments. Flower diameter was decreased by diniconazole 200 mg  L -1.  These results suggest that diniconazole can be used for the control of height in potted ‘ New Orleans ’ chrysanthemum. But additional research is needed to identify responsiveness to cultivars and the application timing and the influence of environment. Fig. 1. The effect of diniconazole concentrations on the height of potted chrysanthemum ‘ New Orleans ’. Chemical Concentration (mg  L -1 ) No. of leaves Leaf area per plant (cm 2 ) Chlorophyll content (SPAD value) Stem Diameter (mm) Control a z a27.8 c4.6 b Diniconazole a807.5 b36.3 b4.8 ab b571.5 d33.8 b4.7 b b cd36.5 b5.0 ab b680.9 c41.9 a5.3 a Daminozide2, b555.2 d34.2 b4.7 b Z Mean separation within columns by Duncan ’ s multiple range test, P=0.05 Table 1. Effect of concentrations of diniconazole on the growth of potted chrysanthemum ‘ New Orleans ’. Chemical Concentration (mg  L -1 ) Days to flowering z No. of flowers Flower diameter (cm) Control0 78 y 39.2 a7.2 a Diniconazole b7.3 a b7.3 a b7.4 a b6.8 b Daminozide2, b7.4 a z Days to flowering was recorded as the number of days after planting y Mean separation within columns by Duncan ’ s multiple range test, P=0.05 Table 2. Effect of concentrations of diniconazole on the flowering of potted chrysanthemum ‘ New Orleans ’.