| Summary: | 碩士 === 國立臺灣大學 === 園藝學研究所 === 85 ===
As the high growth rate and various growth forms, vines can have greening effect rapidly and spaciously although only small space is required. However, presently the information of vines in limited in Taiwan, and plants are susceptible to drought and shade stress caused by buildings in urban areas. In addition, vines attach other objects to grow upward, and the greening effect is influced by the growth rate and the time required for climbing up the trellis.
Firstly, the relations between xylem structure and xylem sap flow rate were investigated. The major plant materials were Clerodendrum speciosum, Quisqualis indica, and Pseudocalymma alliaceum, as the popular vines in Taiwan, together with shrub Duranta repens cv. Golden Leaves. The results showed that the maximum vessel diameter and the large vessel density were higher in three vines than those in D. repens cv. Golden Leaves. The total vessel density in new shoot was higher than those in woody branch in all tested vines. But vessel diameter was higher in woody branc. C. speciosum had the highest percent vessel areas, then the P. alliaceum, and Q. indica was the lowest. C. speciosum also had the highest large vessel density and maximum vessel diameter. Next, sap flow rate was measured by using Flow2 stem-flow gauges. The results showed that C. speciosum had the highest sap flow rate, then the P. alliaceum, and Q. indica was the lowest. Therefore, the vessel diameter and the percent vessel areas were positively related to sap flow rate.
The survey of growth rate showed that the ranking of the daily growth rate and internode length were C. speciosum, Q. indica, P. alliaceum, and F. Pumila respectivly. The growth rate was positive related to photosynthesis and transpiration. The growth rate in P. alliaceum and C. speciosum was promoted by Gas treatments, contrasting to no or little responses in F. pumilla and Q. indica respectively. Gas of 100 ppm was suggested, as there was no marked difference between 100 ppm and 200 ppm treatments, and the 200 ppm treatment would cause plants with smaller leaves and thinner stem on some occasions.
To select species with drought and shade tolerance, some parameters were used including simplicity index of drought tolerance- leaves water lose rate, relative water content, and shade tolerance- changes of relative leaf chlorophyll content. The experimental plants were popular vines in Taiwan —L. japonica, C. sicyoides 'Ovata', V. elliptica, A. leptopus, Q. indica, C. speciosum, P. venusta, A. cathartica, and P. alliaceum. The drought tolerance of tested plants could be divided into three groups: 1)strong, L. japonica, C. sicyoides 'Ovata', V. elliptica, and A. cathartica. 2)medium, A. leptopus, Q. indica, and C. speciosum, 3)mild, P. venusta and P. Alliaceum. The shade tolerance of tested plants could be divided into three groups: 1)strong, L. japonica, and C. speciosum. 2)medium, C. sicyoides 'Ovata' and P. Venusta. 3)mild, V. elliptica, A. cathartica, A. leptopus, Q. indica, and P. Alliaceum.
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