- 期刊
- OpenAccess
台灣油杉側枝扦插發根能力與新梢生長惰性
Rooting Ability of Plagiotropic Cuttings of Keteleeria davidiana Var. formosana and Topophysis of Sprouting Shoots of Stecklings
摘要
1997年9月採集10株15年生與4株70年生台灣油杉單株的插穗進行扦插試驗，插穗分別處理以0、3000、5000ppm IBA粉劑與Chee發根液－由2000ppm IBA+1000ppm NAA+0.08% thiamine組成，從第22週開始到32週結束，每隔5週檢查1次插穗發根率、發根數、與發根長。結果顯示單株間的發根率範圍從22.5到100%，差異顯著。低樹齡單株的插穗發根較早且發根率較高，高樹齡樹冠下層插穗具有幼年葉特徵，其發根率高於採自樹冠上層具有成熟葉特徵的插穗。Chee發根液比其他處理可促進插穗提早發根且發根較長，3000ppm IBA處理優於其他處理，可獲得平均70％之發根率，尤其是對70年生樹插穗處理最為有效。來自15年生扦插苗的頂芽抽芽率以經生長激素處理過較高。觀察二列葉序扦插苗新梢的葉序排列與傾斜角度的變化，發現以3000ppm IBA處理的扦插苗的新梢有較高的螺旋葉序比率及較低的傾斜角度。對高樹齡單株的扦插苗抽芽率，則以5000ppm IBA處理最佳，唯不論任何處理，這些扦插苗所抽出的新梢葉序均成螺旋葉序。由於台灣油杉林木的直立性主梢的葉序都為螺旋排列，因此具有低傾斜角度與直立性螺旋葉序新梢的扦插苗可能可繼續保持其直立性。
並列摘要
Plagiotropic cuttings of Keteleeria davidiana var. formosana were collected from 10 trees aged 15 yr and 4 trees aged 70 yr in September 1997. Cuttings were treated with 0, 3000, and 5000 ppm IBA powder, and with Chee solution composed of 2000 ppm IBA, 1000 ppm NAA, and 0.08% thiamine. Rooting percentages, numbers, and lengths were determined once every 5 wk during the period from 12 to 32 wk. The results showed that rooting percentages varied significantly among trees and ranged from 22.5% to 100%; cuttings from younger trees rooted earlier and better than did those from old trees. The cuttings with juvenile leaves from the bottom crown of old trees obtained higher rooting percentages than did mature leaves from the top crown. Chee solution enhanced cuttings as they rooted earlier and had longer root lengths when compared to those of other treatments. However, treatment with 3000 ppm IBA gave an average of 70% rooting percentages which was greater than with other treatments, especially for the cuttings from 70 yr-old trees. All hormone treatments induced more shoots sprouting from 15ys-old tree-derived stecklings than from the controls. Leaf arrangement and plagiotropic angles of sprouting shoots from steckings with needles arranged in 2 ranks were observed. For younger tree-derived stecklings, 3000 ppm IBA treatment obtained greater numbers of sprouting shoots with spiral-arranged leaves and smaller plagiotropic angles. While for older tree-derived stecklings, 5000 ppm IBA gave greater numbers of sprouting shoots than did other treatments. However, regardless of treatment, all sprouting shoots had spiral leaves. Since the leaf arrangement of orthotropic shoots is spiral in trees, steckling shoots with smaller plagiotropic angles and spiral leaf arrangements might have the potential to become orthotropic with further growth.