| Summary: | 碩士 === 國立臺灣大學 === 園藝暨景觀學系 === 107 === This trial inspected the temperature difference of leaves after exposed to light intensity 150 μmol•m-2•s-1 and 32±0.5℃ degrees in 30 common ornamental plants and used GFS-3000 to determine the photosynthesis potential under light intensity 400, 800, 1200 μmol•m-2•s-1. The results showed that the temperature changes of sun plants and shade plants are -3.1℃ to -0.47℃ and -0.16℃ to 4.95℃, respectively. It is a very simple and fast way but the angle of the leaf and moisture condition should be tended to avoid large deviation. The photosynthesis potential values of shade and sun plant are 3-7 μmol CO2•m-2•s-1and 7-12 μmol CO2•m-2•s-1, respectively. This survey method is more rapid than the conventional method; therefore, it can be used as the approach to determine the light requirements of plants.
The light intensity at the production phase has huge impacts on the quality of ornamental plants. Most of the production of ornamental plants in Taiwan use shade cultivation with light intensity of 100 μmol•m-2•s-1 and 200 μmol•m-2•s-1, therefore being more suitable for common low light intensity environment of indoor. However, the light saturation points of ornamental plants on the market right now (most>400 μmol•m-2•s-1) are higher than the current production light intensity. To ensure the production quality, industry reduced the light intensity at the production phase to prolong the production time. But a few kinds of plants can grow under the full light condition and quickly showed the etiolation and defoliation phenomenon if moved into indoor environment and lower the ornamental life span. Therefore, before the sales, at least 3 to 6 months of acclimation treatment is essential for plants to adapt to weak light before the sale to preserve the reputation. The light acclimation is that plants can adjust their LCP on their own. This ability is very different from each species. In this chapter, we use the Salvia splendens ‘Vista Red’, Aglaonema ‘Silver Queen’, Impatiens hawkeri ‘Divine Blue Pearl’, Radermachera sinica to mimic the situation that plants were moved from native growing environment to indoors for 2 to 3 weeks after the 3, 7, 10 or 14-days light acclimation treatment to access the conditions of acclimation by observing the exterior and physiological quality of plants in non-destructive survey methods. Results indicated that plants altered their exterior and physiological to adapt to different environments. Based on the outcomes of this trial, we can know that the ornamental quality can be improved by 100 μmol•m-2•s-1 acclimation for 7-10 days before being moved into the low light condition but the effects are various from each species and the temperature difference can be used as the non-destructive indicators to investigate the acclimation conditions.
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