修剪與溫度對長實金柑開花與生長之影響

Abstract

本試驗利用不同月份修剪及溫度處理，探討長實金柑（Fortunella margarita Lour. Swingle.）生長與開花的行為。台北及宜蘭地區的長實金柑在未修剪的狀態下，一年有四次抽梢期，分別於三至四月、四至五月、六至八月與八至九月，開花期集中在六至九月，除了第一次抽梢及秋天萌出的第四次梢之外，每次抽梢均會開花。強修剪後之長實金柑植株，第ㄧ次梢皆為營養芽。2006年起盆栽試驗中，不同月份修剪處理的結果顯示，2006年十一月、十二月，2007年一月、二月、三月及四月修剪者，均於2007年五至六月抽出第二次梢時方開花。五月及六月修剪者，在七月抽出第二次梢時開花。七月修剪者，抽梢後隨即出現頂芽著生花苞並開花。八月以後修剪者即不再開花。其中八月修剪者，在九月及十月抽出第二次梢，九月修剪者，在十月抽出一次梢。十月弱修剪者，在十月抽出一次梢；強修剪則無抽梢。無論修剪強度，所有處理皆在次(2008)年三月及四月抽出第一次梢，五月和六月抽出第二次梢，六月底抽出第三次梢並伴隨開花。 田間試驗之修剪處理的結果顯示，2007年四月、五月、六月、修剪者，於七月抽出第二次梢時方開花。七月及八月修剪者，在七及八月抽出第一次梢時，隨即出現頂芽著生花苞並開花。八月修剪者，在九月及十月抽出第二次梢。九月修剪者，在十月抽出一次梢，當年未開花。十月至十二月修剪者，當年無抽梢和開花。、一月及二月修剪者，於三月抽出一次梢。兩地區之所有處理皆在2008年三月及四月抽出第一次梢，五月和六月抽出第二次梢，六月底抽出第三次梢並伴隨開花。 在四種日/夜溫度，35/30，30/25，25/20及20/15℃處理下，以35/30℃處理者於處理後第2週開花為最早，30/25℃處理者於處理後第7週開花，對照組則在第14週開花，25/20℃及20/15℃處理則無開花。綜合以上結果顯示，高溫是誘導長實金柑花芽形成與開花的條件。

Oval Kumquat (Fortunella margarita (Lour.) Swingle) has four flushes per year, which occur in March to April, April to May, and June to August, respectively under natural condiction in Taipei and Yi-Lan.Unlike other citrus plant it did not flowering in spring flush but flowering in June to August on the first, second and third flush. The fourth flush bud burst in autumn will not flowering. In this experiment, potted kumquat and the kumquat plant in Yi-Lan were treated in 2006 with pruning and temperature to discuss how they affected growth, flower formation, and the time of budburst and anthesis. The first flushes of kumquat after moderate pruning or heavy pruning of potteed experiment in 2007 November, December, and 2008 in January, February, March and April were all vegetative flushes, and the flower buds occurred after during third flushes come out. The plant pruning with moderate and heavy pruning in May and June, the second flushes sprouted in July and anthesised in late July. The plants pruning in July, but bud bursted immediately and anthesised on the apex. Pruning in August, September, and October, flushes were all vegetavive and did not flowering in current year. The time of the first flushed budburst of all the plant, occured in March to April, the second flushes bud burst in May to June, and the third flushes bud burst in June. The first, second and third flushes anthesised in June 2008. The first flushes of kumquat after heavy pruning of field experiment were all vegetative flushes in 2007 April, May, June, September, October, November, December, and in 2008 January and February, expect the plant pruning in July, and the flower buds occurred during the third flushes come out in late June. Heavy pruning in July and August, the flushes sprouted after a week for treated. And anthesised on the first flushes immediately at the apex. The plant growth and flowering was almost the same as those in pot experiment. The plant treated with day/night temperature 35/30, 30/25, 25/20, 20/15℃ to check their responses. After 35/30℃ treated for 2 weeks, flower was observed in every flush. 30/25℃ treated for 7th week the flower were occurred on the second flush and lasting to 10th week. The plants of control were anthesis in 14th week on second flush. Both of 25/20 and 20/15℃ were vegetative until 14th week. The result indicated 25℃ should be the most critical factor that induced kumquate flower bud formation and flowering.