The Study of Grafting Methods in Euphorbia pulcherrima Willd. ex Klotzsch

本研究以聖誕紅''Supjibi''、''Peter Star''、''Double''、''P8408''、'' Freedom''、''V-14 Marble''及''Annette Hegg Dark Red''品種為材料，探討 如何提高聖誕紅嫁接存活率及嫁接後對植株高度之影響。''Supjibi''、'' Freedom''及''V-14 Marble''嫁接存活率試驗發現，盆接在第一星期內，嫁 接植株即大量死亡，死亡率超過50%，而接插在第一星期內，死亡率低 於5%，三星期以後嫁接植株才大量死亡，因此認為乳汁會影響嫁接存活率 。砧木與接穗在留葉數和長度的比較，砧木長由10公分增加至15公分，不 留葉至留8~10片葉片，接穗長由7公分至10公分，不留葉至留一片葉片， 存活率從1%提昇至90%以上。以石臘切片觀察聖誕紅嫁接癒合之情形，發 現嫁接十天後癒合組織即充滿砧木與接穗之間。 聖誕紅不易長側枝者嫁 接於易長側枝者，會促進不易長側枝者長側枝，使橫向生長增加，減少縱 向生長達到矮化目的。不易長側枝品種''Supjibi''、''Double''及''P8408''嫁 接於易長側枝品種''V-14 Marble''及''Annette Hegg Dark Red''，側枝數與 對照組比較皆有明顯的差異，但高度方面只有''Double''及''P8408''有明顯 差異，尤其是''Double''嫁接於''Annette Hegg Dark Red''，經摘心後高度 具有極顯著差異。This study was tried to increase the survival rate of grafted poinsettia and grafting effect on plant height by using poinsettia cvs. Supjibi, Peter Star, Double, P8408, Freedom, V-14 Marble, and Annette Hegg Dark Red.In survival study of poinsettia cvs. Supjibi, Freedom and V-14 Marble, results showed that over 50% pot grafting plants died and under 5% grafted cutting plant died in the first week. However, lots of grafted cutting plants died after the third week. Therefore, it was considered that exudates would effect the survival of grafted poinsettia. In comparison of length and leaf number of both stock and scion, as stock length increased from 10 cm to 15 cm with leaf number keeping from 0 to 8 or 10; and as scion length increased from 7 to 10 cm with leaf number keeping from 0 to 1, the survival rate increased from 1% to 90% and above. Callus are established between stock and scion 10 days after grafting in transverse section of paraffin embedded observation.The restricted-branching cultivars will increase their branching potential if restricted-branching cultivars were grafted onto freed-branching cultivar, This study was tried to increase branching occurrence (horizontal growth), and to inhibit the vertical growth. Significant difference in branching occurrence were demonstracted when restricted-branching poinsettia cvs. Supjibi, Double and P8408 was grafted onto free-branching cultivar cvs. V-14 Marble, and Annette Hegg Dark Red. There were also significant differences in height after pinching when ''Double'' poinsettia was grafted on ''Annette Hegg Dark Red''