發根劑、品種與光度對於九重葛扦插繁殖之影響

Abstract

九重葛(Bougainvillea spp.)通常以無性繁殖的方式進行繁殖，國內九重葛業者在盆花生產上多選擇使用高壓繁殖，但如要大量生產，則繁殖倍率高的扦插繁殖是較合適的方式。九重葛扦插繁殖多使用成熟度高的硬木插穗，但是硬木插穗取得較困難，若能使用容易取得的軟木插穗扦插，將能更快速的量產一致性的苗木，故本文以九重葛軟木插穗進行扦插繁殖試驗，並找出適合軟木插穗的藥劑處理、取穗條件，並探討品種差異以及遮陰處理之影響，以改善軟木插穗扦插不易的問題，建立九重葛軟木扦插繁殖之方法。 生長素(auxin)種類與施用的方式(粉劑或液劑)對於九重葛‘Pixie’插穗發根的影響的試驗結果可得知，頂芽插穗處理6,000 mg·L-1 IBA(indole-3-butyric acid)粉劑或6,000 mg·L-1 NAA(1-naphthaleneacetic acid)粉劑，效果皆優於液劑，其中以6,000 mg·L-1 NAA粉劑插穗發根率(52%)優於IBA處理。九重葛‘Pixie’取穗部位對於發根影響的試驗結果可得知，九重葛‘Pixie’上半部枝條的插穗發根率為96.7%，下半部枝條的插穗的發根率達100%，兩者無顯著差異，不過，九重葛‘Pixie’上半部枝條插穗發根品質略優於下半部枝條，但無論上半部(不含頂芽)或下半部枝條的插穗，兩者都能得到品質很好的扦插苗，因此後續如要進行九重葛‘Pixie’的扦插繁殖，兩種插穗都可以使用，最大化材料使用效率以及扦插生產效益。 從品種對於九重葛軟木插穗發根能力影響的試驗中可得知，九重葛‘Singapore Pink’與‘Pixie’不處理發根劑的情況下，插穗發根率分別達到93.3%與80%，是容易發根的品種。九重葛‘Eva’與‘Taipei Red’插穗不處理發根劑發根率低落，經處理6,000 mg·L-1 IBA粉劑後，發根率顯著提升至73.3%與76.7%，九重葛‘Markris’與‘Imperial Delight’處理IBA 6,000 mg·L-1粉劑後，發根有顯著提升至23.3%與36.7%，但是發根率仍低，表示發根劑雖然有促進九重葛插穗發根的效果，但會受到品種的影響。九重葛‘Thimma’經處理發根劑後依然沒有發根，且插穗皆死亡，此品種可能為不容易發根的品種。對於發根能力不佳的品種，後續進一步處理高效複合發根劑(根旺發NO. 3)，探討高效複合發根劑是否比單獨處理生長素(IBA或NAA)有促進軟木插穗發根的效果，試驗結果顯示根旺發NO. 3粉劑顯著促進九重葛‘Markris’與‘Thimma’發根率與插穗品質，發根率分別提升至100%及66.7%，而對於九重葛‘Taipei Red’效果不顯著，推測根旺發NO. 3對於發根困難的品種有促進發根的效果，但對於易發根的品種效果則不顯著。對於不易發根的花木類植物，根旺發NO. 3用於促進發根可能具有相當大的潛力。 扦插環境光度方面，九重葛‘Pixie’在夏季進行70%遮陰處理(平均光強度318 μmol.m-2.s-1)，插穗品質最佳且發根率可達100%。85%遮陰處理(平均光強度140 μmol.m-2.s-1)下的插穗發根品質不佳，發根速度較慢，發根率也較低。秋季時，九重葛‘Markris’以70%遮陰處理(平均光強度164.8 μmol.m-2.s-1)，插穗有最佳發根率為87.6%，85%遮陰處理(平均光強度76.8 μmol.m-2.s-1)的插穗發根率最差為53.3%，發根品質方面，則以50%遮陰處理(平均光強度237.1 μmol.m-2.s-1)較佳；九重葛‘Thimma’以50%遮陰處理發根最佳，九重葛‘Taipei Red’扦插存活率低，可能與插穗營養狀態及環境變化有關。綜合上述結果，強度合適的光照有助於九重葛插穗的發根，夏季時氣候穩定，但是容易有光強度過高的問題，夏季時扦插遮陰70%較佳。秋季時光強度減弱，以50-70%遮陰處理效果較佳，。然而，扦插時85%的遮陰處理(平均光強度低於140 μmol.m-2.s-1)會顯著抑制插穗的發根，因此建議九重葛扦插時光強度可在200-400 μmol.m-2.s-1之間。 本研究對於九重葛軟木插穗的品種差異、取穗條件、藥劑處理以及扦插光強度環境有進一步的了解，並成功提升九重葛軟木插穗的扦插成功率，總結以上試驗結果建立九重葛軟木插穗扦插繁殖技術，解決九重葛扦插繁殖生產苗木的問題。

Bougainvillea (Bougainvillea spp.) is usually reproduced by non-sexual propagation. Domestic bougainvillea famers often choose to use laying propagation for pot flower production. However, if massive production is necessery, cutting propagation with higher propagation rate is a more appropriate method for grower. The technigue for bougainvillea cutting propagation mostly uses mature hardwood cuttings. However, hardwood cuttings are more difficult to obtain. Therefore, by using easy-to-obtain softwood cuttings massive production might become practicable. So the goal of this study is founding on using bougainvillea softwood citting propagation method to find out suitable chemical treatments and cutting taking conditions for softwood cuttings, and discussing the differences of varieties and the influence of shading treatments. To solve the problem of difficult cuttings of softwood cuttings, and establish a practicable method for the propagation of bougainvillea softwood cuttings. According to the results of the effect of auxin type (IBA or NAA) and application method (powder or liquid) on the rooting of ‘Pixie’ bougainvillea cuttings The top bud cuttings treated with 6,000 mg·L-1 IBA(Indole-3-butyric acid) powder or 6,000 mg·L-1 NAA (1-Naphthaleneacetic acid) powder are better than solution treatment. The rooting percentage of cuttings with 6,000 mg·L-1 NAA powder is significantly better than others. The rooting percentage of 'Pixie' bougainvillea cuttings that obtain from upper half of the branches is 96.7%, and the rooting percentage of cuttings that obtain from lower half of the branches is 100 %, there is no significant difference between the two. However, the rooting quality of the upper half branch cuttings is slightly better than the lower half branch cuttings. Both the upper half (excluding the top buds) and the base half of the cuttings can acquire good quality cuttings. Suggesting two kinds of cuttings can be used to cutting propagation. Not only maximize the resourse usage efficiency but also promote the cutting production efficiency. Base on the result of rooting ability trooting ability.‘Singapore Pink’ and ‘Pixie’ bougainvillea cuttings without treated the rooting-inducer and rooting percentage of cuttings are 93.3% and 80%. Suggesting both cultivars are suitable for cutting prapagation. ‘Eva’ and ‘Taipei Red’ bougainvillea cuttings without treating rooting stimulator have lower rooting percatage than the rest. The ‘Eva’ and ‘Taipei Red’ bougainvillea cuttings were treated with 6,000 mg·L-1 IBA powder, and the rooting percentage was significantly increased to 73.3% and 76.7%. ‘Markris’ and ‘Imperial Delight’ bougainvillea cuttings treated with IBA 6,000 mg·L-1 powder, the rooting percentage increased significantly to 23.3% and 36.7%, but rooting percentage was still low. Although the rooting stimulator has a good effect on promoting rooting capability of bougainvillea cuttings, but the effect is different between cultivars. All ‘Thimma’ bougainvillea cuttings were perished, suggesting ‘Thimma’ bougainvillea is difficult for rooting. Rooting stimulator NO. 3 powder has the best effect of promoting the rooting of softwood cuttings than IBA or NAA. The rooting percentage of ‘Markris’ and ‘Thimma’ bougainvillea cuttings increased to 100% and 66.7%. Hoever, ‘Taipei Red’ bougainvillea cutting that treated with rooting stimulator NO. 3 is not significant affected. This result suggest that rooting stimulator NO. 3 has the good effect of promoting rooting for cultivar that difficult to root, but has no effect on cultivar that easy to root. For cultivars that have low rooting percentage, rooting stimulator NO. 3 may have considerable potential for promoting rooting. ‘Pixie’ bougainvillea cutting undet 70% shading treatment (average light intensity is 318 μmol.m-2.s-1) in summer, and the cutting rooted quality were the best and the root percentage reaches 100%. Cuttings rooting quality under 85% shading treatment(average light intensity is 140 μmol.m-2.s-1) was poor and the cuttings rooting speed was slow, and the rooting percentage was also low. In autumn, when ‘Markris’ bougainvillea cutting was put under 70% shading treatment (average light intensity is 168.4 μmol.m-2.s-1) enivvroment, the cuttings had the best root percentage of 87.6%. Onvertheless, under 85% shading treatment (average light intensity is 76.8 μmol.m-2.s-1), cuttings had the worst root percentage of 53.3%. Under 50% shading treatment (average light intensity is 237.1 μmol.m-2.s-1), cuttings have best rooting quality. ‘Thimma’ bougainvillea cuttings had best rooting under 50% shading treatment. All ‘Taipei Red’ bougainvillea cuttings survival percentage was low during experiment, which may be related to unstable environment. According to the experiment result, applying appropriate intensity of light is helpful for the rooting of the bougainvillea cuttings. Summer season is good for cutting propagation, but it could have excessive light intensity during dat time. In summer, the optimum shading percsntage is 70%. In autumn, the light intensity was weakened, therefore the optimum shading percsntage is between 50-70%. However, the cuttings under 85% shading treatment (average light intensity lower than 140 μmol. μmol.m-2.s-1) will significantly inhibit the rooting. Therefore, when applying cutting propagation on bougainvillea, the optimum light intensity should between 200-400 μmol.m-2.s-1. This study has a better understand on the effects of the cultivar differences of bougainvillea softwood cuttings, under diffferent season, cutting conditions, chemical treatments and light intensity environment. By summarizing all experemants results.A practicable cutting propagation technigue were established, whitch may solves the problem of bougainvillea cutting propagation and production of cutting seedlings.