修剪對長實金柑（Fortunella margarita (Lour.) Swingle）生育特性之影響

Studies of Pruning on Growth and Flowering of Kumquat (Fortunella margarita (Lour.) Swingle)

幸沛華(Pei-Hua Xing) ； 林連雄(Lian-Hsiung Lin) ； 張允瓊(Yung-Chiung Chang)

《宜蘭大學生物資源學刊》 13卷 (2017/12) Pp. 65-79

https://doi.org/10.6175/job.201712_13.0014

摘要

為探討不同時間及不同程度修剪對長實金柑枝條生長與開花之影響，本研究以3年生之盆栽金柑為試驗材料，分別於2、4、6及8月初進行強剪及弱剪以觀察植株生育變化。強剪為去除樹冠幅度1/2量之修剪，弱剪則去除1/4，並以未修剪植株作為對照。結果未修剪處理之金柑植株一年內可萌梢3次，分別於4月初、5月上旬及8月上旬萌梢。參試植株除8月修剪處理組僅於當年抽梢2次外，其餘月份處理組植株皆可於當年抽梢3次。不同程度修剪對金柑植株之一及二次梢之枝條生長具顯著影響，修剪時間愈早，且較高強度之修剪處理，枝條長度較長且徑寬較粗，但8月後之修剪，強剪對一次梢生長不具促進效果。不同時間及程度之修剪對植株之開花數皆具顯著性影響，且兩者間對開花數具交互作用。早期修剪有利增加植株之開花數量，但修剪強度愈高，開花數亦下降愈明顯。而不同時間及程度之修剪對植株之果實數量、座果率、成熟果及未成熟率亦具顯著性影響。金柑植株經強、弱剪後皆可提升座果率，且強剪處理之增加效果較明顯；於6月份後進行強、弱剪之植株，因果實發育時間不足，成熟果比例明顯下降。綜言之，藉由早期修剪，可提昇金柑枝條生長勢及座果率，對樹勢控制及果實生產具正面效益，而6月份後之修剪，因萌發之枝梢早熟而生長量不足，不具生產潛質。

關鍵字

長實金柑 ； 修剪 ； 枝條生長 ； 開花

並列摘要

This study was to investigate the effect of time and level of pruning on shoot growth and flowering of kumquat (Fortunella margarita (Lour.) Swingle). Three-year-old potted trees were heavy and light pruned on 1st February, 1st April, 1st June, and 1^(st) August, 2016, respectively. The heavy and light pruning treatments were to remove half and one-fourth the length of shoot from the branches, respectively. The un-pruned kumquat tree displayed three times of new shoot sprouting in one year, which the 1st flush occurred in early April, then the 2^(nd) flush appeared in early May and the 3^(rd) flush emerged in August. The trees pruned in February, April, and June also had three times of new shoot sprouting in one year, however trees pruned in August only sprouted new shoot twice in one year. Pruning time and level displayed significant effects on the shoot growth of the 1^(st) and 2^(nd) flushes. Moreover, the earlier of the time pruning and the more of the pruning amount, the longer and wider of the shoot length and diameter were. In the other hand, early pruning increased the flower number of the kumquat trees; however, as the pruning amount increased the flower number decreased. Pruning time and level also displayed significant effects on the fruit number, fruit set ratio, ripe fruit ratio, and unripe fruit ratio. Once the pruning time later than June was, the ripe fruit ratio of kumquat trees significant decreased because of the insufficient shoot growth. Consequently, early pruning of the kumquat trees increased the shoot growth and fruit set ratio that might offer an effective strategy for tree growth control and fruit production promotion.

並列關鍵字

kumquat ； pruning ； shoot growth ； flowering