The Tolerance of Environmental Plants to Ozone and Sulfur Dioxide

• Main Authors: Shuai-Ju, Chen, 陳帥如
• Other Authors: Yu-Sen Chang
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/07581247042026546269

碩士 === 國立臺灣大學 === 園藝學研究所 === 92 === Environmental plants were exposed to different levels of ozone (O3) or Sulfur dioxide (SO2). The fumigation results indicated that camphor tree (Cinnamomum camphora) had the best resistance to O3 in all tested trees, followed by narrow-leaved oak (Quercus myrsinifolia), Chinese babyberry (Myria rubra), flame goldrain tree (Koelreuteria henryi), Taiwan pittosporum (Pittosporum pentandrum), and Taiwan zelkova (Zelkova serrata). Camphor tree also had the best resistance to SO2, followed by Taiwan pittosporum, narrow-leaved oak, Chinese babyberry, flame goldrain tree, and Taiwan zelkova. In all tested shrubs, ceylon ardisia (Ardisia squamulosa) had the best resistance to O3 or SO2, followed by common jasmine orange (Murraya exotica L.), Crape myrtle (Lagerstroemia indica), rose of sharon (Hibiscus syricacus L.), Chinese hibiscus (Hibisicus rosa-sinensis), and golden dewdrop (Duranta repens). In all tested bedding plants, ornamental pepper (Capsicum annuum) had the best resistance to SO2, followed by globe-amarantha (Gomphrena globosa), Madagascar periwinkle (Catharanthus roseus), mealy sage (Salvia farinacea), torenia (Torenia fourieri), zinnia (Zinnia anngustufolia). There was a significantly positive correlation (R2 = 0.7511***) between the air pollution tolerance index (APTI) (before fumigation) and O3-resistance. But the relationship between the APTI and SO2-resistance showed no significant correlation. However, there was a significantly positive correlation between chlorophyll content or relative water content and SO2-resistance. After O3 or SO2 fumigation treatment, the content of ascorbic acid in plants was increased. However, the chlorophyll content, relative water content and leaf thickness were decreased. The leaf-extract pH value of the O3 fumigation treatment was increased, whereas that of SO2 fumigation treatment was decreased. In order to increase the experimental efficiency, the evaluation of in vitro system was processing. After 6 hours of O3 treatment, the stomata of golden dewdrop and Taiwan cherry of cutting shoots showed the similar behavior as those of potted plants. The base of shoot should be re-cut in water to maintain the stomata opening. On the choice of vase solution, the distilled water or preservative solution (8-HQS 50 ppm + AgNO3 20 ppm) was suggested. For the same plant species, the injury level of O3 fumigation treatment in cutting shoots was significantly lower than that in potted plants; whereas on SO2 fumigation treatment, the injury level between the cutting shoots and potted plants showed no significant difference. Because the resistance sequence of all tested plants to O3 or SO2 were similar between the system of cutting shoots and that of potted plants. Therefore, it is suggested that the in vitro system is feasible to evaluate the resistance of plants to O3 or SO2. Stomatal conductance usually decreased when O3 or SO2 treatments. The results showed that a significantly positive correlation (R2 = 0.8127***) between relative stomatal conductance (RSC) and O3 injury. The plants that had lower level of RSC also had the lower level of O3 injury. However, there was a significantly negative correlation (R2 = 0.7311***) between RSC and SO2 injury. The plants that had lower RSC also had the higher level of SO2 injury. Therefore, it is assumed that stomatal closure during fumigation period is an adaptation response to O3 and an injury response to SO2. The chlorophyll fluorescence (Fv/Fm) was decreased with the higher level of O3 or SO2 treatment. The results revealed that a significantly negative correlation between relative chlorophyll fluorescence and the foliage injury of O3 or SO2. For In vitro system, the decreasing level of chlorophyll fluorescence also indicated the injury level of plants. The fumigation results of flame goldrain tree and Taiwan pittosporum showed that the foliage injury of O3 treatment occurred firstly on mature leaves, and that of SO2 treatment occurred firstly on younger leaves. The mature leaves, those were more sensitive to O3 may result from that the ascorbic acid content and stomatal closure during fumigation period of mature leaves were less than those of younger leaves. In addition, the younger leaves those had higher stomatal conductance and lower chlorophyll content or leaf-extract pH value than other leaves may result in those younger leaves more sensitive to SO2.