Abstract:The ability of in vitro micropropagtion to produce high quality planting material in large quantities is hindered by their high cost of production. Hence the price of planting material is high, making them unaffordable to growers. However, a larger portion of the capital and running cost of micropropagation can be reduced using CSUP (pronounced as seesap) technique, where sodium hypochlorite is used to sterilize glassware and culture media followed by culturing without using a laminar flow cabinet. This study was undertaken with the objective of evaluating the feasibility of the CSUP technique to replace the sterilization carried out using autoclaves and laminar flow cabinets.Sodium hypochlorite in four concentrations 5, 10, 15 and 20% (v/v) were used to rinse glassware and accessories prior to pouring the appropriate culture medium for anthurium cv 'Tropical Red' in vitro shoot multiplication. The culturing of axenic shoots was carried out inside a glass-cage and cultures were placed in the growth room. Autoclaved culture medium and a laminar flow cabinet were used in the case of the control cultures. Results revealed that the percentage of contaminationfree cultures, dry weight increase and the shoot multiplication were not significantly different between the respective treatments and the controls, as well as among treatments of different sodium hypochlorite concentrations. Therefore, the CSUP technique using 5% (v/v) sodium hypochlorite solution can be adopted to replace the use of an autoclave and the laminar flow cabinet in the major micropropagation activity of in vitro multiplication.

ABSTRACT. Poinsettia (Euphorbia pulcherrima

No abstract

Production of attractive marketable poinsettia (Euphorbia pulcherrima) pot plants throughout the year can be achieved by forced blooming in the off season, but it is necessary to study their post production conditions and public acceptability prior to marketing. The poinsettia pot plants produced in the off season, when evaluated on its acceptability by the general public through a questionnaire, indicated that 76.6 % of the participants accepted it as a suitable pot plant for indoor decorations in local festivals. In the experiments conducted to evaluate retention of attractiveness of poinsettia under different indoor conditions, mainly at different light levels, it was revealed that leaves, bracts and bract color of these artificially-induced plants remained more than 8 weeks under 1600-4000 lux light level. Almost all leaves and more than 50 % of colorful bracts dropped under the 1-50 lux, and 50-200 lux light levels within the first four weeks while their color reduced to 50 %.

An experiment was conducted in a shade house to determine the effects of three shade levels on leaf area and biomass production of three varieties of dracaena (Dracaena sanderiana L.) in the dry zone (Batticaloa district) of Sri Lanka. 'Gold', 'Victory' and 'White' varieties were arranged in 50%, 70% and 80% shade levels as a CRD. There was a significant interaction between varieties of dracaena and the shade levels on leaf area and biomass production. The plants grown at 50% and 70% shade levels produced the highest leaf area and biomass than plants subjected to 80% shade. Biomass production was in accordance with the trend of variances for leaf area. Varieties 'Gold' and 'Victory' performed better than 'White' in leaf area and biomass production under 50% and 70% shade level and there were no significant variations between them. Therefore, in this study it was concluded that, 70% shade level is suitable for growing dracaena varieties in the dry zone of Sri Lanka as the growth of dracaena varieties were higher than the other shade levels.