EFFECTS OF IRRIGATION FREQUENCY ON ROOT-FORMATION AND SHOOT GROWTH OFSPRAY CHRYSANTHEMUM CUTTINGS IN SMALL JUTE PLUGS

Small plugs of organic, fibrous material (jute) were used as a propaga tion medium for spray chrysanthemum cuttings instead of the more conve ntional, pre-fertilized compressed peat blocks. A complete nutrient so lution was supplied to the jute plugs by means of ebb-and-flow irrigat ion. Four different irrigation frequencies (IF) were compared, i.e. 96 , 24, 6 and 1 day(-1). During the root initiation stage, the irrigatio n treatments had little effect on the cuttings. Once a new root system had been generated, a strong positive correlation between IF and grow th was observed. Shoots of rapidly growing cuttings contained relative ly high levels of nutrients and low non-structural carbohydrate levels and had a high turgor. These results demonstrate that during propagat ion from cuttings, growth may be limited by the availability of water and minerals. In the case of chrysanthemum cuttings in small jute plug s, factors limiting growth can be overcome by frequent irrigation with a complete nutrient solution.