插穗直徑、發根劑以及扦插時期對九重葛插穗生長之影響

Effects of Cutting Diameter, Rooting Agent and Inserting Time on the Growth of Bougainvillea glabra Cuttings

以‘紫花’與‘台北紅’九重葛為試驗材料，探討不同插穗直徑、IBA（indole butyric acid）和ABT等發根劑以及扦插時期對扦插發根之影響。‘紫花’以直徑3～6 mm、‘台北紅’以直徑3～6 mm及6～9 mm的插穗有較佳的發根率，直徑3 mm以下及9 mm以上的插穗發根率普遍較低。兩品種以3000 ppm及6000 ppm的IBA粉劑處理，普遍較未處理者有更好的發根率，其中以6000 ppm處理者其發根率明顯優於3000 ppm處理者和未處理者。以三種不同ABT之液劑和粉劑處理‘紫花’，其中以100 ppm的1號ABT液劑處理者有較高的發根率。而在IBA與1號ABT的比較試驗中，‘紫花’以6000 ppm的IBA粉劑處理，其促進發根效果優於100 ppm的l號ABT液劑和6000 ppm的1號ABT粉劑處理者；‘台北紅’方面，則以100 ppm的1號ABT液劑及6000 ppm的l號ABT粉劑處理者的發根效果優於6000 ppm的IBA粉劑處理者。另次試驗中，7500 ppm的1號ABT粉劑處理對兩品種之發根效果均明顯優於6000 ppm的IBA粉劑處理。此外，扦插季節亦會影響九重葛的發根率，多次的試驗結果顯示夏季高溫多濕時期（7月至10月）扦插的插穗，其發根率普遍較其他月份扦插者為低，此可能與此討驗期間高溫、日照強且多、以及雨量過多有關。

Bougainvillea 'Purple Flower' and 'Taipei Red' were used to evaluate the effects of cutting diameters, rooting agents snob as IBA (inodole butyric acid) and ART, and inserting limes on the growth of cuttings. The results showed that rooting ratios were higher in 3-6 mm-diameter-cuttings of 'Purple Flower' and 3-6 mm-and 6-9 mm-diameter-cuttings of 'Taipei Red'. The rooting ratios were low in the castings from tip (＜3 mm-diameter) and basal (＞9 mm-diameter). Treating with 6000 ppm IBA powder could significantly increase rooting ratio than 3000 ppm IRA and control in both cultivars. Treating with three different ART (No. 1, No. 2, and No. 3) solution and powder on 'Purple Flower' indicated that 100 ppm ART No. 1 solution had greater rooting ratio. In the comparison of IRA and ART No.1, rooting ratio of 'Purple Flower' was higher when treated with 6000 ppm IBA powder than that treated with 100 ppm ART No. 1 solution or 6000 ppm ABT No. 1 powder. On the contrary, rooting ratios of 'Taipei Red' when treated with ART No. 1 solution and powder were higher than treated with IBA powder. For both 'Purple Flower' and 'Taipei Red', 7500 ppm ART powder treatment had greater rooting ratio than 6000 ppm IBA powder treatment. Moreover, the rooting ratio was also affected by inserting time. Results showed that high temperature and high humidity n summer (from July to October) would decrease the rooting ratio. Therefore cutting propagation of bougainvillea in summer should be avoided, It is suggested that in order to increase rooting ratio, propagating bougainvillea from cuttings should be carried out in spring or autumn in Taiwan and combine with 6000 ppm IBA or 7500 ppm ART No. 1 powder treatment.