孫蘇南,王小德,徐騰,章宬,王開利,鄧磷曦
(浙江農(nóng)林大學風景園林與建筑學院,浙江臨安 311300)
落羽杉秋冬季葉色變化的生理生態(tài)研究
孫蘇南,王小德,徐騰,章宬,王開利,鄧磷曦
(浙江農(nóng)林大學風景園林與建筑學院,浙江臨安 311300)
為探討落羽杉Taxodium distichum秋冬季葉色變化規(guī)律,研究落羽杉在不同光照、溫度和不同生境條件下葉色轉變時的生態(tài)生理變化,以落羽杉成齡植株為材料,于2012年8月下旬至11月中旬用分光光度計測定其不同方位與不同生境條件下葉片葉綠素總質(zhì)量分數(shù)、花色素苷相對含量和可溶性糖質(zhì)量分數(shù)。結果表明:秋冬轉色期落羽杉葉片葉綠素總質(zhì)量分數(shù)呈下降趨勢,樹冠背陰面葉片葉綠素總質(zhì)量分數(shù)明顯高于向陽面,向陽東面高于向陽西面;花色素苷相對含量呈上升趨勢,11月5日之后顯著升高;可溶性糖質(zhì)量分數(shù)呈上升趨勢;日平均氣溫與花色素苷相對含量、可溶性糖質(zhì)量分數(shù)間呈負相關;水生落羽杉葉綠素總質(zhì)量分數(shù)、花色素苷相對含量、可溶性糖質(zhì)量分數(shù)均高于陸生落羽杉,水生落羽杉紅葉觀賞期較陸生落羽杉長,它們的花色素苷相對含量與葉綠素總質(zhì)量分數(shù)呈顯著負相關(P<0.05)。光照充足條件下,生長在水中的落羽杉紅葉期要長于陸生的,且有較好的整體觀賞性。圖8表3參20
植物生理學;落羽杉;秋冬轉色期;生理指標;變化趨勢
落羽杉Taxodium distichum是古老的孑遺植物,具有生長快、干形直、材質(zhì)好、耐腐朽、耐水濕、適應性廣等優(yōu)點,自被引種到歐洲、亞洲、非洲、大洋洲后,成為了這些地區(qū)生態(tài)環(huán)境建設、用材造林、園林景觀應用的重要樹種。落羽杉高大挺拔,樹冠圓錐形,葉片春夏由嫩綠轉為深綠,秋冬季轉為紅褐色,是園林造景較廣泛的秋冬季紅色葉樹種。落葉樹木秋季葉色變化與其葉片組織中和呈色相關的葉綠素、類胡蘿卜素、生物堿類色素和黃酮類色素的含量有關[1-2],葉色變紅是由于葉片中大量合成黃酮類色素中的花色素苷的結果[3],而花色素苷生物合成受多種因子誘導,如溫度、光、營養(yǎng)供給、生長調(diào)控、代謝物以及組織的特殊發(fā)育階段等[4-7],其中溫度在葉色呈色過程中起著重要的調(diào)控作用。目前,針對落羽杉秋冬轉色期葉色素和可溶性糖含量變化尚未見相關報道。本試驗以落羽杉成齡植株為材料,研究秋冬轉色期不同光照強度、不同氣溫、不同朝向、不同生境條件下落羽杉葉片葉綠素、花色素苷和可溶性糖含量的變化,為其園林造景應用提供理論支持。
1.1 試驗材料
以浙江農(nóng)林大學東湖校區(qū)具有典型代表的成齡落羽杉植株為試材。選取樹齡相近、長勢良好、生長環(huán)境一致(地勢開敞,光照充足)的植株,不同生境條件為陸生與水生2種類型。
1.2 方法
1.2.1 取樣試驗于2012年8月下旬至11月上旬進行,取樣時間為上午8:00-9:00,隔10 d采樣測定1次。為探究落羽杉不同朝向葉片葉色變化,采樣分向陽和背陰,向陽又分東西2個朝向,共3個處理,設重復3次·處理-1[8-9]。每次都在標記部位剪取適量葉片,取回后立即洗凈、擦干,去掉主脈后剪碎、混勻,存放于4℃冰箱中保鮮,為葉綠素、花色素苷和可溶性糖的測定備用[10]。
1.2.2日平均溫度檢測取樣當天用溫濕度儀Testo 610測定當天溫度,求出日平均氣溫。
1.2.3 生理指標測定采用丙酮浸提法測定葉綠素總含量[11]:取0.2 g樣品于15 mL體積分數(shù)為80%的丙酮中,暗處浸提24 h至葉片變白,整個過程不斷搖動;取上清液用UV-2550型紫外分光光度計測定645,652,663 nm處的吸光度值D(λ),以體積分數(shù)為80%丙酮作對照,計算葉綠素總質(zhì)量分數(shù)?;ㄉ剀障鄬繙y定采用鹽酸浸提法[12]:取0.5 g樣品于15 mL體積分數(shù)為1%的鹽酸乙醇中,在暗處浸提24 h,期間不斷搖動,以體積分數(shù)為1%鹽酸乙醇作對照;以每克鮮質(zhì)量在10mL提取液中D(λ)0.1為1個色素單位,計算和比較花色素苷的相對含量。采用蒽酮比色法測定可溶性糖質(zhì)量分數(shù)[13]。
1.3 數(shù)據(jù)分析
將試驗數(shù)據(jù)進行分類整理,實驗數(shù)據(jù)測定均為3次重復,使用SPSS11.5軟件進行數(shù)據(jù)分析,Microsoft Excel 2003作圖。
2.1 落羽杉同株不同方位秋冬轉色期葉片色素和可溶性糖質(zhì)量分數(shù)變化
2.1.1 葉綠素總質(zhì)量分數(shù)變化由圖1知:秋冬轉色期落羽杉葉片葉綠素總質(zhì)量分數(shù)呈先慢后快下降趨勢,背陰面葉片葉綠素總質(zhì)量分數(shù)顯著高于向陽面,向陽東面高于向陽西面。這與西照太陽的光照強度強、光照時間長,引起西向的葉片葉綠素分解相對較快有關[14]。
2.1.2 花色素苷相對含量變化由圖2知:秋冬轉色期落羽杉花色素苷相對含量呈上升趨勢,開始較為緩慢,11月5日之后迅速升高,樹冠葉片迅速轉為紅棕色的時間與實地觀察相吻合;從朝向來看,落羽杉花色素苷相對含量為向陽西面>向陽東面>背陰面。
2.1.3 花色素苷相對含量與葉綠素總質(zhì)量分數(shù)比值變化由圖3知:落羽杉秋冬轉色期花色素苷相對含量與葉綠素總質(zhì)量分數(shù)比值呈逐漸上升趨勢,且向陽西面>向陽東面>背陰面,11月5日之后比值迅速上升,此時葉子顏色最為亮麗鮮紅,向陽西面葉片尤為明顯,與實地觀察到的陽面葉色轉色較快相吻合,表明花色素苷相對含量與葉綠素總質(zhì)量分數(shù)和它們的比值影響著落羽杉葉片的顏色變化。
圖1 秋冬轉色期落羽杉葉綠素總質(zhì)量分數(shù)變化Figure 1 Variation of total chlorophyll contents of Taxodium distichum during the color-changing period in autumn and winter
圖2 秋冬轉色期落羽杉花色素苷相對含量變化Figure 2 Variation of total anthocyanin relative contents of Taxodium distichum during the color-changing period in autumn and winter
2.1.4 可溶性糖質(zhì)量分數(shù)變化由圖4知:落羽杉秋冬轉色期可溶性糖質(zhì)量分數(shù)呈逐漸上升趨勢,由快到慢變化;不同朝向的可溶性糖質(zhì)量分數(shù)為向陽西面>向陽東面>背陰面。
圖3 秋冬轉色期落羽杉花色素苷相對含量與葉綠素總質(zhì)量分數(shù)比值變化Fig ure 3 Variation of ratio on anthocyanin and chlorophyll content of Taxodium distichum during the colorchanging period in autumn and winter
圖4 秋冬轉色期落羽杉可溶性糖質(zhì)量分數(shù)變化Fig ure 4 Variation of soluble sugar contents of Taxodium distichum during the color-changing period in autumn and winter
2.1.5 葉綠素、花色素苷、可溶性糖的方差分析從表1知:同株不同方位落羽杉葉片色素和可溶性糖質(zhì)量分數(shù)存在一定的差異性;葉綠素總質(zhì)量分數(shù)為背陰面>向陽東面>向陽西面,但它們間無顯著差異;花色素苷相對含量為向陽西面>向陽東面>背陰面,且它們間呈顯著差異;可溶性糖質(zhì)量分數(shù)為向陽西面>向陽東面>背陰面,且它們間也呈顯著差異??梢?,光照強度、光照時間對葉綠素的分解和花色素苷的合成有直接的影響。
表1 落羽杉不同方位花色素苷相對含量、可溶性糖和葉綠素總質(zhì)量分數(shù)方差分析Table 1 Analysis of variance of the anthocyanin,soluble sugar,chlorophyll content of Taxodium distichum in different positions of cypress
2.1.6 溫度與葉綠素總質(zhì)量分數(shù)、花色素苷相對含量、可溶性糖質(zhì)量分數(shù)的相關性分析由圖5知:試驗過程中日平均氣溫總體呈現(xiàn)下降趨勢。由表2知:溫度與各朝向葉片花色素苷相對含量呈顯著(P<0.05)或極顯著(P<0.05)負相關,與可溶性糖質(zhì)量分數(shù)呈負相關,與葉綠素總質(zhì)量分數(shù)呈現(xiàn)極顯著正相關。
2.2 不同生境條件下落羽杉秋冬轉色期葉片色素和可溶性糖變化
2.2.1 陸生與水生落羽杉葉綠素總質(zhì)量分數(shù)變化由圖6知:秋冬轉色期陸生與水生落羽杉葉片葉綠素總質(zhì)量分數(shù)呈下降趨勢,且水生落羽杉葉綠素總質(zhì)量分數(shù)下降較陸生落羽杉快;水生落羽杉葉綠素總質(zhì)量分數(shù)高于陸生落羽杉。這與胡永紅等[15]關于秋色葉葉色變化的研究結果相吻合,空氣相對濕度高對葉綠素的降解和花色素苷的合成有促進作用。
圖5 試驗期間日平均氣溫Figure 5 Daily average temperature during the experiment
圖6 秋冬轉色期落羽杉葉綠素總質(zhì)量分數(shù)變化Figure 6 Variation trends of total chlorophyll contents during the color-changing period in autumn and winter
表2 秋冬轉色期氣溫與落羽杉花色素苷相對含量、可溶性糖質(zhì)量分數(shù)、葉綠素總質(zhì)量分數(shù)相關系數(shù)Table 2 Correlation coefficients between temperature and anthocyanin or soluble sugar content or chlorophyll content of Taxodium distichum during the color-changing period of cypress in autumn and winter
2.2.2 陸生與水生落羽杉花色素苷相對含量變化由圖7知:陸生與水生落羽杉秋冬轉色期花色素苷相對含量呈上升趨勢,11月5日后上升加快,與實地觀察到的落羽杉葉片迅速轉為紅棕色時間相一致;水生落羽杉花色素苷相對含量高于陸生落羽杉,與實地觀察水生落羽杉紅葉觀賞期較陸生落羽杉長相吻合。
2.2.3 陸生與水生落羽杉可溶性糖質(zhì)量分數(shù)變化由圖8知:陸生與水生落羽杉秋冬轉色期可溶性糖質(zhì)量分數(shù)呈上升趨勢,先快后慢;11月5日之后,可溶性糖質(zhì)量分數(shù)變化較慢,趨于穩(wěn)定;水生落羽杉可溶性糖質(zhì)量分數(shù)高于陸生落羽杉。
圖7 秋冬轉色期落羽杉花色素苷相對含量變化Figure 7 Variation trends of anthocyanin relative contents of Taxodium distichum during the color-changing period in autumn and winter
圖8 秋冬轉色期落羽杉可溶性糖質(zhì)量分數(shù)變化Figure 8 Variation trends of soluble sugar contents of Taxodium distichum during the color-changing period in autumn and winter
2.2.4花色素苷與葉綠素、可溶性糖質(zhì)量分數(shù)的相關性分析由表3知:秋冬轉色期落羽杉花色素苷相對含量與葉綠素總質(zhì)量分數(shù)呈負相關,其中陸生落羽杉為顯著負相關、水生落羽杉為極顯著負相關,而與可溶性糖質(zhì)量分數(shù)的相關性不顯著。
光照強度、光質(zhì)和光照時數(shù)等對彩葉植物花色素苷的合成及調(diào)節(jié)相關酶的活性起著重要作用[16],光照可以使葉綠素、花色素苷的含量及比例發(fā)生變化,對葉片的顏色變化產(chǎn)生影響。秋冬轉色期落羽杉同株不同方位葉片葉綠素呈下降趨勢,花色素苷相對含量與可溶性糖質(zhì)量分數(shù)均呈上升趨勢;不同方位葉片花色素苷相對含量與可溶性糖質(zhì)量分數(shù)差異性顯著(P<0.05);不同方位花色素苷相對含量為向陽西面>向陽東面>背陰面,說明向陽西面光照時數(shù)長、光照強度強對花色素苷的合成有利。這與Saure[17]認為入秋后隨著葉綠素的降解,花色素苷合成加快的研究結果相一致,葉綠素的降解物可能對于花色素苷的形成起到活化作用。
秋冬季低溫可以誘導植物體內(nèi)花色素苷的合成,光合色素在低溫下合成受阻,從而引起植物葉色變化[18-19]。唐前瑞等[20]認為葉片中花色素苷的合成和衰老期間糖分的積累有相關關系。實驗結果顯示,落羽杉秋冬轉色期葉片花色素苷和可溶性糖質(zhì)量分數(shù)均呈上升趨勢;日平均氣溫與葉綠素總質(zhì)量分數(shù)呈正相關,與花色素苷相對含量呈顯著負相關。當溫度下降至17.7℃時,花色素苷相對含量急劇上升,達到4.75(色素單位),實驗結果證明低溫有利于花色素苷的積累。
試驗結果與實地觀察顯示,水生落羽杉秋冬轉色期、彩葉觀賞期較陸生落羽杉的時間長,如將落羽杉配植在水邊或水中,其秋色葉更能展現(xiàn)景觀效果。
表3 秋冬轉色期落羽杉花色素苷相對含量與葉綠素總質(zhì)量分數(shù)及可溶性糖質(zhì)量分數(shù)的相關系數(shù)Table 3 Correlation coefficientsbetween anthocyanin and chlorophyll or soluble sugar content of Taxodium distichum during the colorchanging period in autumn and winter
[1]祝欽瀧.彩葉草葉色形成相關的花色素苷生物合成途徑的分子調(diào)控研究[D].重慶:西南大學,2007.
ZHU Qinlong.Studieson the Molecular Regulation of the Anthocyanin Biosynthesis Related to Leaf Color of Solenostemon scutellarioides[D].Chongqing:Southwestern University,2007.
[2]VAKNIN H,BARAKIVA A,OVADIA R,et al.Active anthocyanin degradation inBrunfelsia calycina(yesterday-today-tomorrow)flowers[J].Planta,2005,222(1):19-26.
[3]KIM JS,LEE B H,KIM SH,et al.Responses to environmental and chemical signals for anthocyanin biosynthesis in non-chlorophyllous corn(Zearmays L.)leaf[J].JPlant Biol,2006,49(1):16-25.
[4]BAN Y,KONDO S,UBI B E,et al.UDP-sugar biosynthetic pathway:contribution to cyanidin 3-galactoside biosynthesis in apple skin[J].Planta,2009,230(5):871-881.
[5]AHMED N,MAEKAWA M,NODA K.Anthocyanin accumulation and expression pattern of anthocyanin biosynthesis genes in developing wheat coleoptiles[J].Biol Plant,2009,53(2):223-228.
[6]張劍亮.觀賞向日葵花色形成的機理研究[D].福州:福建農(nóng)林大學,2008.
ZHANG Jianliang.Study on the Formation of Flower Color from Ornamental Sunflower(Helianthus annuus)[D].Fuzhou:Fujian Agriculture and Forestry University,2008.
[7]孫明霞,王寶增,范海,等.葉片中的花色素苷及其對植物適應環(huán)境的意義[J].植物生理學通訊,2003,39(6):688-694.
SUN Mingxia,WANG Baozeng,F(xiàn)AN Hai,et al.Anthocyanins of leaves and their environmental significance in plant stress responses[J].Plant Physiol Commun,2003,39(6):688-694.
[8]于曉南,張啟翔.觀賞植物的花色素苷與花色[J].林業(yè)科學,2002,38(3):147-153.YU Xiaonan,ZHANGQixiang.Anthocyanin in ornamental plant and color express[J].Sci Silv Sin,2002,38(3):147 -153.
[9]陳繼衛(wèi),沈朝棟,賈玉芳,等.雞爪槭轉色期葉色變化生理研究[J].核農(nóng)學報,2010,24(1):171-175.
CHEN Jiwei,SHENChaodong,JIAYufang,etal.Physiologicalchanges of Japanesemaple(Acerpalmatum Thunb)leaves during color-changing period[J].JNucl Agric Sci,2010,24(1):171-175.
[10]馬海燕,李永,鄭春雷,等.4種植物生長調(diào)節(jié)劑對切花菊保鮮效果和生理作用的影響[J].河南農(nóng)業(yè)大學學報,2012,46(3):278-283.
MA Haiyan,LIYong,ZHENG Chunlei,et al.Influence of four plant growth regulators on vase life and physiological action of cut chrysanthemum[J].JHenan Agric Univ,2012,46(3):278-283.
[11]李得孝,郭月霞,員海燕,等.玉米葉綠素含量測定方法研究[J].中國農(nóng)業(yè)通報,2005,21(6):153-155.
LIDexiao,GUO Yuexia,YUAN Haiyan,et al.Determined methods of chlorophyll from maize[J].Chin Agric Sci Bull,2005,21(6):153-155.
[12]ZHANG Feng,WANG Jianhua,YU Songlie,et al.Study on daily changes of photosynthesis inCynanchum bungei[J].Acta Bot Boreal-Occident Sin,2005,25(2):288-292.
[13]路文靜,李奕松.植物生理學實驗教程[M].北京:中國林業(yè)出版社,2012:54-57.
[14]陳繼衛(wèi),沈朝棟,賈玉芳,等.紅楓秋冬轉色期葉色變化的生理特性[J].浙江大學學報:農(nóng)業(yè)與生命科學版,2010,36(2):181-186.
CHEN Jiwei,SHEN Chaodong,JIA Yufang,et al.Physiological changes ofmaple(Acer palmatum‘Atropurpureum,)leaves during the color-changing period in autumn and winter[J].JZhejiang Univ Agric&Life Sci,2010,36(2):181-186.
[15]胡永紅,秦俊,蔣昌華,等.上海地區(qū)秋色葉成因的調(diào)查與分析[J].東北林業(yè)大學學報,2004,32(5):84-86.
HU Yonghong,QIN Jun,JIANG Changhua,et al.Investigation and analysis on cause of forming autumn-color leaf in Shanghai[J].JNortheast For Univ,2004,32(5):84-86.
[16]李紅秋,劉石軍.光照強度和光照時間對色葉樹種葉色變化影響[J].植物研究,1998,18(2):194-205. LIHongqiu,LIU Shijun.Effects of light intensity and illumination time on leaf color variations of colored leaf trees [J].Bull Bot Res,1998,18(2):194-205.
[17]于曉南,張啟翔.彩葉植物多彩形成研究進展[J].園藝學報,2000,27(增刊):533-538.
YU Xiaonan,ZHANG Qixiang.Review of researches on leaf color changing of color leafed plants[J].Acta Hort Sin,2000,27(supp):533-538.
[18]潘增光,王國賓,李奎明,等.新紅星蘋果果實著色期幾種色素含量變化及其相關性(簡報)[J].植物生理學通訊,1996,32(5):347-349.
PAN Zengguang,WANG Guobin,LI Kuiming,et al.Change of some pigment contents and their correlation skin coloring stage in‘Starkrimson,apple[J].Plant Physiol Commun,1996,32(5):347-349.
[19]費芳,王慧穎,唐前瑞.溫度對紅花檵木葉色的影響研究[J].湖南理工學院學報:自然科學版,2008,21(2):88-90.
FEIFang,WANG Huiying,TANG Qianrui.Study on the impact of temperature onLoropetalum chinese var.rubrumleaves color[J].JHunan Inst Sci Technol Nat Sci Ed,2008,21(2):88-90.
[20]唐前瑞,陳德富,陳友云,等.紅花檵木葉色變化的生理生化研究[J].林業(yè)科學,2006,42(2):111-115.
TANG Qianrui,CHEN Defu,CHEN Youyun,et al.Changes of physiology and biochemistry during leaf color transformation inLoropetalum chinense var.rubrum[J].Sci Silv Sin,2006,42(2):111-115.
Ecological physiology of Taxodium distichum leaves color changes in autumn and winter
SUN Sunan,WANG Xiaode,XU Teng,ZHANG Cheng,WANG Kaili,DENG Linxi
(School of Landscape Architecture,Zhejiang A&F University,Lin,an 311300,Zhejiang,China)
To explore the rule of cypress leaf color changes in autumn and winter,and study the physiological characteristics under different illumination,temperature and habitat conditions,the mature cypress trees,(Taxodium distichum)variations of chlorophyll,anthocyanin and soluble sugar content in its leaves were measured during the color-changing period from late August to early November by spectrophotometry.The results indicated that the chlorophyll content descended gradually.The chlorophyll content in the leaves in the shady side was significantly higher than that in the sunny side,and that in the east of the sunny side was significantly higher than the west.The anthocyanin content kept ascending slowly before November 5th and increased significantly since then.The soluble sugar content increased gradually.During the experiment,there was a negative correlation between daily average temperature and anthocyanin content,or soluble sugar content. Chlorophyll,anthocyanin and soluble sugar contents of cypress which grown in the water were less than those grown in the field.The red-leaf period of cypress trees which were grown in the water was longer than those grown in the field,and there was a significantly negative correlation(P<0.05)between anthocyanin and chlorophyll content.Under the adequate sunlight,red-leaf period of cypress trees grown in the water was longer than those grown in the field,and the former had higher ornamental values.[Ch,8 fig.3 tab.20 ref.]
plant physiology;cypress(Taxodium distichum);color-changing period in autumn and winter;physiological index;variation trend
S718.43
A
2095-0756(2014)02-0302-06
2013-01-05;
2013-03-02
孫蘇南,從事園林植物應用與效益評估等研究。E-mail:sunsunan1988@163.com。通信作者:王小德,教授,博士,從事園林植物引種與應用、植物造景和生態(tài)園林等研究。E-mail:wxd65@zafu.edu.cn