華山松種子發芽與不同階段之低溫層積處理改變華山松種子胚部激勃素和離層酸濃度之研究

Changes of gibberellins and abscisic acid levels in embryos of Pinus armandii var. mastersiana seeds during different stages of cold stratified treatment

許弘諭(Hong-Yu Shy)

指導教授 ： 王亞男

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.00538

摘要

華山松種子具有休眠性，若在發芽前將華山松種子處以10週的5℃低溫層積處理，則種子發芽率將從原本的16％增加至20％。此外，在不同發芽溫度試驗中發現華山松種子最適合的發芽環境是在10℃/20℃的變溫條件下，其發芽率明顯優於20℃/30℃與15℃/25℃。

對於層積處理可以提高種子發芽力的現象，利用GC-MS-SIM對經過2、4、6週低溫層積處理的不同階段華山松種子胚部做ABA(Abscisic acid)GAs (Gibberellins）化學物質研究，發現這段期間內激素的變化量以ABA最為明顯，ABA濃度在低溫層積處理初期較高，每1g乾重的華山松胚部細胞中有250ng的ABA，但是在經過4週低溫層積處理的樣品中則發現ABA有減少的趨勢，濃度降至1g乾物重中有約150ng左右的，濃度減少了40％，直至6週之後濃度都維持在1g乾重胚部細胞中有150ng的ABA含量。推測低溫層積處理對於華山松體內ABA濃度的影響是將其濃度降低至一定值。

GAs是影響種子發芽的激素，在2、4、6週低溫層積處理期的不同階段中發現，在第2週時所偵測到的種類以GA4為最大宗，其後濃度變化漸減，而在第6週時偵測到GA1濃度大量增加，顯示在低溫層積處理期間，種子內部已經開始產生具有促進發芽的GA種類。

將實驗所得數據比照GA生合成路徑，non-13-hydroxylation pathway與 early 13-hydroxylation pathway兩種，因為實驗中發現到GA4、GA24以及在第6週的樣本中發現大量的GA1，對照GA生合成路徑圖可發現在低溫層積處理期間，華山松種子體內有進行non-13-hydroxylation pathway的GA生合成路徑。

關鍵字

GA ； ABA ； 冷溫層積處理 ； 華山松 ； 種子休眠

並列摘要

Seeds that unable to germinate is a serious problem when people try to breeding seedlings. Pinus armandii ver. mastersiana has low germination percentage and dormancy. Treating its seeds with cold stratification for ten weeks could broke seed dormancy and increase seed germination percentage from 12.5% to 15%. Considered with the viability of seed is 20%. Make this result as 100%. The germination percentage increased from 62.5% to 75%.

Using GC-MS-SIM to detect concentrations of ABA(abscisic acid) and GAs(gibberellins) in P. armandii seed embryos by two weeks, four weeks and six weeks cold stratification. Results showed two weeks cold-stratified had ABA concentration of 262ng per gram dry weight. ABA concentration decreases to 179 ng per gram dry weight at cold-stratified for four weeks. It was 31% reduction. At the cold-stratified for six weeks, the concentration of ABA was 155 ng per gram dry weigh. The decrease of ABA concentration could be one of the reasons that seed germination increase after cold stratification.

The changes of GAS concentrations were great found in P. armandii seed embryos. The concentration of GA3 was detected after cold stratification for two weeks which was 37.5 ng per gram dry weigh. But it disappeared at samples which after four weeks cold stratification, in which GA3 replaced with GA1 to be the main GAS. GA4 and GA24 were also detected in the sample which after four weeks cold stratification. GA1 was detected at the cold-stratified for six weeks embryos. Results showed GA syntheses pathway in the embryo was proceed by non-13-hydroxylation pathway during cold stratification. This syntheses pathway is lack of function to produce GA1. Cold stratification to P. armandii seed embryos was increase the ability to produce GA1.

Seed dormancy is a complicate mechanism for plants. By studying different kinks ofplants, tissues and germination stage can help us to realize the main factors of seed dormancy. At the feature, the study of breaking seed dormancy could enhance seed germination and increase the amount of seedlings.

並列關鍵字

GA(Gibberellins) ； ABA (Abscisic acid) ； cold stratification ； Pinus armandii ； seed germination ； seed dormancy

參考文獻

古森本。2008。生質能源作物之開發與潛力。植物種苗生技 13:46-53。

宋妤、張仁銓。2004。溫度及光線對芹菜種子發芽之影響。中國園藝50: 157-166。

侯金日。2004。溫度、種子水分含量及氧氣對毛豆及烏豆種子儲藏壽命之影響。、環境與生物資訊。1: 171-190

陳舜英。2008。山櫻花和楊梅種子之休眠及解除機制。國立台灣大學森林環境暨資源研究所博士論文。

楊翎翎、林正斌、劉景平。2007。淹水對苜蓿種子發芽及萌芽之影響。中華農學。8: 265-274。