The culture practice of croton (Codiaeum variegatum)cutting and the photosynthetic characters of six croton cultivars

• Main Authors: Deng-Fu Liu, 劉登富
• Other Authors: Wen-Ju Yang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/12260968751431663612

碩士 === 國立臺灣大學 === 園藝學研究所 === 94 === Summary Croton(Codiaeum variegatum) is a perennial woody foliage plant, which is used landscaping commonly. However, by improving the cutting quality and accommodating to lower light, croton can be potentially developed to be indoor plants. The objective of this study was to build a standard cutting procedure and evaluated the lower light tolerance of the common cultivars in Taiwan. In the study of the effect of nodal position on rooting of the cuttings of ‘Andreanum’ and ‘MacArthurii’, the data suggested that leaves at apical position, cutting length may resulted in better rooting. Besides, due to the diameters of the cuttings we selected were larger than ~0.5cm, the effect of cutting diameter on rooting was not observed. The result of the effect of leaf retention number on the rooting of ‘Andreanum’ cutting indicated that the cuttings with more than 4 leaves were preferred for rooting. The effect of IBA application on rooting was cultivar dependent. Application higher concentration of IBA to ‘Andreanum’ cuttings resulted in more rooting, shorter root length and less weight. However, the effect was not observed in ‘MacArthurii’cutting. The result of rooting experiment in the phytotron indicated that 25/20℃ resulted in more roots and 30/25℃ resulted in longer roots with higher dry weight. Besides, heating up the soil temperature to 23-25℃ was also suggested for winter production. The six croton varieties expressed higher leaf area and specific leaf area, longer internodes, lower specific leaf weight, thinner leaf due to the decreased length of palisade tissues, and decreased number of stomata under shading. Besides, leaf variegation ratio was observed higher under shading. In general, croton is sun plant, and their light saturation and compensation points were decreased in response to shading. Under 80% shading, light compensation point of the 6 cultivars were about 13.63 to 20.12 μmol m-2s-1, which indicating croton is sun-shade plant and potentially an indoor pot plant depending on cultivar.