環刻對荔枝花芽分化的影響

Effect of Girdling on Flower Differentiation of Litchi (Litchi chinensis Sonn)

以石蠟切片法，觀察‘黑葉’荔枝於白露期間環刻後，芽體發育之歷程。第一年之觀察發現，在環刻前荔枝頂芽多屬於營養狀態；環刻後，頂芽伸長，並且葉腋基部之芽原體開始發育而形成側芽原體，隨後有一段發育停止期；在當年的寒流來臨後，側芽原體即迅速發育，形成次級及三級分枝的花序原體。次年，將荔枝分為環刻與不環刻兩群，環刻前後每月每樹選樹取頂芽解剖調查營養芽轉生殖芽之比例。其中，環刻樹之生殖芽比例約70.0%左右，對照樹之生殖芽比例約45.0%。春天開花前，再調查荔枝之純花序、帶葉花序及營養梢之比例，環刻樹分別為58.9%、31.4%、9.7%，對照樹則分別為28.4%、44.7 %、26.9%。 This is a two years observation for the effect of girdling on ‘Haak Yeh’ litchi bud differentiation. Before girdling, the terminal bud is under vegetative condition. After girdling, the apex elongated and lateral bud initiated, then the bud cease development before the temperature was drop down. After cold current arrived (around Nov. 16, 2001), it will develop again, then the lateral bud primordia developed very fast and inflorescence elongated with initiating floret primordium. The second year, the trees were divided equally into girdling (treated) and non­girdling (CK) treatment. The reproductive bud of treated trees is about 70% while CK is about 45%. In the spring, the percentage of leafless panicles, leaf panicles and vegetative shoots of treated trees are 58.9%, 31.4%, 9.7%, respectively, and those of CK trees are 28.4%, 44.7%, 26.9%.