共查询到19条相似文献，搜索用时 187 毫秒
1.
2.
三种松树叶绿素荧光特征比较研究 总被引：1，自引：0，他引：1
以赤松、油松、白皮松3种松树为材料,利用便携式调制荧光仪MINI-PAM测定自然条件下其各叶绿素荧光参数Ft、Fm、Yield、ETR、qP、qN或NPQ和PAR指标的日变化。结果表明:3种松树各个时段荧光参数值在总体上差异不大,叶绿素荧光参数的变化依赖于PAR的变化。Ft、rETR、qN和NPQ的变化与PAR的变化趋势一致,Fm、Yield和qP的变化与PAR的变化相反。其中,白皮松的量子产量Yield、相对光合电子传递速率ETR、光化学淬灭系数qP、非光化学淬灭系数qN和NPQ均高于赤松和油松,说明其能通过增加热耗散来尽量降低光抑制程度,对当地环境较为适应。本研究为3种松树抗性研究、苗木管理、科学种植等提供了生理指标和依据。 相似文献
3.
对菊花在长期低浓度SO2情况下光合色素含量和叶绿素荧光特性进行了研究.结果表明:用0.3 mg.L-1的SO2处理1周,引起菊花叶片光合色素含量显著增加,叶绿素荧光动力学曲线明显下降,表观电子传递速率(E)、非环式电子传递的量子效率(Y)和光化学淬灭系数(qp)有所增加;熏气至6周,叶绿素荧光动力学曲线和非光化学淬灭系数(qN)显著升高,光合色素含量显著下降,PSII反应中心潜在活性(FV/F0)、E和Y明显降低,而对PSII原初光能转换效率(FV/Fm)和qp的影响较小. 相似文献
4.
研究了持续高温干旱胁迫条件下禾本科C4植物香根草的光合特性和几种生理指标的变化.结果表明:在整个高温干旱胁迫过程中土壤相对含水量、香根草叶片相对含水量及叶绿素含量均呈下降趋势,而丙二醛(MDA)含量和游离脯氨酸(Pro)含量持续增加,抗氧化物酶类(SOD、POD)活性先升高后降低.胁迫初期香根草叶片的净光合速率(Pn)、细胞间CO2浓度(Ci)显著下降.随着胁迫程度加剧,PSII最大光化学量子产量(Fv/Fm)、PSII有效光化学量子产量(Fv'/Fm')、光化学猝灭(qP)、非光化学猝灭(qN)、电子传递速率(ETR)下降.表明高温干旱胁迫初期光合速率的下降是由于气孔关闭引起,胁迫后期指标变化是由于叶片PSII光合系统受损引起. 相似文献
5.
采用人工气候箱的方法,测定了低温胁迫下葛藤Pueraria lobata、假连翘Duranta repens、老鸭嘴Thunbergia erecta和台湾相思Acacia confuse幼苗的荧光参数,以便为筛选抗寒种类提供依据。结果表明,随着低温胁迫时间的延长,4种幼苗的最大荧光(Fm)、表观电子传递速率(ETR)、PSII实际光量子效率Y(II)逐渐下降,非光化学淬灭(NPQ)先上升后下降,PSII调节性能量耗散Y(NPQ)和PSII非调节性能量耗散Y(NO)逐渐升高。经过24 h自然恢复,4种幼苗的Fm均恢复到对照水平,ETR有所回升,Y(NPQ)恢复到显著高于对照水平;葛藤、老鸭嘴和台湾相思的NPQ保持稳定,假连翘的NPQ有所下降;假连翘和台湾相思的Y(II)恢复到对照水平,葛藤、假连翘和台湾相思幼苗的Y(NO)恢复到对照水平。对荧光参数进行主成分分析表明,干旱胁迫下4种幼苗的抗寒顺序为台湾相思>假连翘>葛藤>老鸭嘴。 相似文献
6.
不同光强下红锥幼苗叶绿素荧光参数的日变化 总被引：1，自引：0，他引：1
测定分布在不同光照强度（全光照、遮荫下光强分别相当于自然光照的80％、30％和20％）的红锥（Castanopsis hystrix）盆栽幼苗叶绿素荧光参数的日变化过程,以探讨红锥幼苗生长对光强的适应性.结果显示,4种生境光强下的叶绿素荧光参数日变化趋势基本一致;低光强下（30％和20％光强）的有效光化学量子产量（Fv＇/Fm＇）、光化学淬灭系数（qP）和最大光能转化效率（Fv/Fm）显著高于高光强下（全光照和80％光强）的对应值,且三者均表现为中午较低,傍晚最高的趋势;相对表观电子传递速率（ETR）和非光化学淬灭系数（NPQ）表现为随生境光强的增加而升高的趋势,低光强下显著低于高光强下的对应值,且两者均表现为傍晚最低.研究表明,红锥盆栽幼苗对低光强的适应性很强,适当遮光有利于提高红锥苗的光合能力. 相似文献
7.
不同生境掌叶覆盆子叶绿素荧光参数比较研究 总被引：1，自引：0，他引：1
研究掌叶覆盆子对环境的适应性,为掌叶覆盆子的栽培管理提供理论依据.以林缘和露地的掌叶覆盆子为研究对象,探讨不同生境下掌叶覆盆子叶绿素荧光参数的日变化规律.结果表明:Fo、Fm和Fv/Fm均呈现先降后升趋势,ETR、qP、NPQ则相反.不同生境下各荧光参数值出现谷值及峰值的时间不同,其恢复程度也有所差异.林缘和露地初始荧光(Fo)出现谷值时间分别为12:00和16:00;最大荧光(Fm)、最大光化学效率(Fv/Fm)均在16:00和14:00降到最低值;而表观光合电子传递速率(ETR)、非光化学淬灭系数(NPQ)峰值出现在10:00-12:00;露地和林缘光化学淬灭系数(qP)在10:00和14:00达到最大值.与林缘相比,露地生境下的掌叶覆盆子在中午强光作用下有较高的光合效率,对强光有更高的适应性. 相似文献
8.
五种观花树种光合与叶绿素荧光特征研究 总被引：2，自引：1，他引：1
光合作用是树木的重要生理指标之一。叶绿素荧光是监测植物光合作用的有效探针。文章对大叶紫薇（Lagertstroemiaspeciosa）、宫粉紫荆（Bauhiniavariegata）、腊肠树（Cassia fistula）、乐昌含笑（Micheliachapensis）、深山含笑（M．maudiae）这五种观花树种的2年生苗木进行了光合特征及叶绿素荧光特征指标的测定,比较了各参数的差异。结果表明：大叶紫薇、宫粉紫荆和腊肠树总体上具有较高的光合指标,而乐昌含笑和深山含笑则相对较低;大叶紫薇、宫粉紫荆和腊肠树总体上的相对电子传递速率ETR、PSII的实际量子产量Y（II）以及非调节性能量耗散的量子产量Y（NO）相对较高于乐昌含笑和深山含笑,而调节性能量耗散的量子产量Y（NPQ）和非光化学淬灭系数NPQ则相反。总体上看,大叶紫薇、宫粉紫荆和腊肠树具有更高的光舍效能和环境适应能力。 相似文献
9.
为了研究不同光照强度对姜科植物叶片叶绿素荧光参数的影响,以益智Alpinia oxyphylla、花叶山姜A.pumila、红柄郁金Curcuma rubescens和花叶艳山姜A. zerumbet ‘Variegata’4种姜科植物为试验材料,在不同遮光处理下测定姜科植物叶片的最大光化学效率Fv/Fm、非光化学淬灭NPQ、实际光能转化效率Y(Ⅱ),光化学淬灭系数qP和表观电子传递速率ETR,综合评价结果显示:4种姜科植物的耐阴性为花叶山姜>花叶艳山姜>益智>红柄郁金。 相似文献
10.
《中南林业科技大学学报(自然科学版)》2016,(9)
采用盆栽试验,研究水分胁迫对刨花润楠幼苗光合生理指标及叶绿素荧光参数的影响,揭示水分胁迫对刨花润楠光合作用及生理指标之间的关系,为刨花润楠苗期水肥管理及栽培提供参考依据。结果表明:在4种水分胁迫下,刨花润楠幼苗的净光合速率、蒸腾速率及气孔导度的日变化均呈双峰曲线,有明显的光合午休现象,轻度干旱(LS)对刨花润楠幼苗的净光合速率(P_n)、初始荧光(F_o)、非光化学猝灭系数(NPQ)无明显影响(P0.05);中度干旱(MS)及重度干旱(SS)均使刨花润楠幼苗叶片叶绿素含量、净光合速率(P_n)、蒸腾速率(T_r)、气孔导度(Gs)、胞间CO_2浓度(C_i)、电子传递速率(ETR)、最大光化学效率(F_v/F_m)、实际光化学量子效率(ΦPSII)、PSII的潜在活性(F_v/F_o)、光化学猝灭系数(qP)及生长显著下降(P0.05);初始荧光(F_o)、非光化学猝灭系数(NPQ)显著升高(P0.05);在轻度干旱和中度干旱胁迫下刨花润楠幼苗光合作用的降低主要是由气孔关闭引起的,而重度干旱胁迫下光合作用的下降主要是由光合机构活性降低的非气孔因素引起的。 相似文献
11.
5种红山茶叶绿素荧光特性的比较研究 总被引：34，自引：3，他引：34
在大四条件下，通过对五种红山茶的叶绿素荧光特性研究，结果表明，不同亚组、同一亚组不同系之间的叶绿素荧光参数值存在差异．且亚组间大于亚组内。初始荧光(FO)、最大荧光(Fm)、RSⅡ最大光化学效率(Fv／Fm)、PSⅡ实际光化学效率(Yield／ΦPSⅡ)、表观电子传递速率(ETR)的日变化与光强有关．其中，Fm、Fv／Fm、Yield随光强的变化呈相同的变化趋势，呈单谷曲线；而ETR则相反呈单峰曲线；FO呈双峰曲线。不同树种的荧光参数日变化幅度存在差异。 相似文献
12.
13.
Porcar-Castell A Juurola E Nikinmaa E Berninger F Ensminger I Hari P 《Tree physiology》2008,28(10):1475-1482
Acclimation of the partitioning of absorbed light energy in Photosystem II (PSII) between photochemical and non-photochemical processes includes short-term adjustments that are rapidly reversed in the dark and seasonal acclimation processes that are unaffected by dark acclimation. Thus, by using dark-acclimated leaves to study the seasonal acclimation of PSII, the confounding effect of short-term adjustments is eliminated. The maximum quantum yield of photochemistry, estimated by chlorophyll fluorescence analysis as F(v)/F(m), where F(v) = (F(m) - F(o)), and F(m) and F(o) are maximum and minimum chlorophyll fluorescence, respectively, has been widely used to follow the seasonal acclimation of PSII, because it is measured in dark-acclimated leaves. Seasonal changes in F(v)/F(m) can be caused by adjustments in either the photochemical capacity in PSII, or the capacity of thermal dissipation in PSII, or both. However, there is a lack of chlorophyll fluorescence parameters that can distinguish between these processes. In this study, we introduce two new parameters: the rate constants of sustained thermal energy dissipation (k(NPQ)) and of photochemistry (k(P)). We estimated k(NPQ) and k(P) from dark-acclimated F(o) and F(m) measured during spring recovery of photosynthesis in Scots pine (Pinus sylvestris L.) trees. We suggest that k(NPQ) and k(P) be used to study the mechanisms underlying the observed seasonal acclimation in PSII, because these parameters provide quantitative data that complement and extend F(v)/F(m) measurements. 相似文献
14.
Quenching analysis in poplar clones exposed to ozone 总被引：1，自引：0，他引：1
Effects of ozone (O(3)) on photo-inhibition of photosynthesis were investigated in two poplar clones (Populus deltoides Bartr. ex Marsh. x maximowiczii A. Henry clone Eridano, O(3)-sensitive, and P. x euramericana (Dode) Guinier clone I-214, O(3)-resistant) by using pulse amplitude modulation chlorophyll fluorescence. After a 15-day exposure to O(3) at 60 nl l(-1) for 5 h day(-1), the effective photosynthetic quantum yield of photosystem II (PSII), as indicated by the ratio of variable to maximum chlorophyll fluorescence, significantly declined in both young and mature leaves of the two clones. Compared with control samples, mature leaves of both clones showed differences in fluorescence quenching and quantum yield of PSII when exposed to ozone fumigation. We conclude that photo-inhibition is caused by transformation of active reaction centers to photochemically inactive centers that dissipate excitation energy into heat, thus causing non-photochemical fluorescence quenching. The changes observed in chlorophyll a fluorescence of O(3)-treated young leaves in both clones are consistent with O(3) having a negligible effect on photosynthetic performance, but inducing a premature decrease in chlorophyll a concentration. A possible role of O(3) pollution on chlorophyll fluorescence yield is discussed. 相似文献
15.
Syringa species not only have good ornamental properties but also play an important role in the landscaping and environmental purification of cities.To investigate the chilling stress resistance of Syringa oblata Lindl.and Syringa reticulata var.mandshurica and provide theoretical grounds for the practical cultivation of Syringa species,in vitro leaves were used to study photosynthetic gas exchange parameters and chlorophyll fluorescence parameters.After nine hours of chilling,decreasing rates of net photosynthesis,stomatal conductance,and transpiration in S.reticulata var.mandshurica leaves were significantly greater than that of the S.oblata,while intercellular CO2 concentrations in S.oblata leaves were higher than those in S.reticulata var.mandshurica.The quantum yield of PSII reaction center(APSII)declined in S.reticulata and light capture efficiency(Fv 0/Fm 0)was stable.However,reduction percentages of Fv 0/Fm 0,APSII,and Fv/Fm in S.oblata were significant higher than those of S.reticulata var.mandshurica.After nine hours of chilling,the relative variable fluorescence of VJ and VI of S.oblata increased and the increasing rate of VJ was greater than VI.In contrast,the change of VJ and VI in S.reticulata var.mandshurica leaves was relatively small.This suggests that chilling primarily damaged the electron transport process of QA to QB at the receptor site of the PSII reaction center.Photosynthetic capacity of S.oblata was more sensitive to chilling stress compared to S.reticulate var.mandshurica,which the limitations were mainly due to non-stomatal factors such as the decrease in electron transport efficiency,activity in the PSII reaction center,and the destruction of the photodamage defense system. 相似文献
16.
Girdling effects on fruitlet abscission, leaf chlorophyll, chlorophyll a fluorescence and carbohydrate concentration in various flowering and vegetative shoots were studied during natural fruit drop in two Citrus cultivars. Irrespective of shoot type, girdling delayed fruitlet abscission, but only fruitlets borne on leafy shoots had increased final fruit set. Chlorophyll a fluorescence analysis revealed differences in quantum yield efficiency of photosystem II of light adapted leaves (Phi(PSII)) among shoot types and in response to girdling. In young leaves of vegetative shoots, girdling decreased Phi(PSII), whereas Phi(PSII) increased from Day 30 after girdling in young leaves of leafy flowering shoots; however, Phi(PSII) did not change in mature leaves during fruit set in either control or girdled trees. Girdling altered leaf carbohydrate concentrations and the photosynthetic performance of the various shoot types. Our results indicate that, in Citrus, several carbohydrate-based regulatory mechanisms of photosynthesis coexist during carbohydrate accumulation brought about by girdling. It is concluded that the delay in fruitlet abscission and the increase in Phi(PSII )observed in girdled leafy flowering shoots are the mechanisms underlying the enhancement of fruit set after girdling. 相似文献
17.
To clarify the changes in plant photosynthesis and mechanisms underlying those responses to gradually increasing soil drought stress and reveal quantitative relationships between photosynthesis and soil moisture,soil water conditions were controlled in greenhouse pot experiments using 2-year-old seedlings of Forsythia suspensa(Thunb.) Vahl. Photosynthetic gas exchange and chlorophyll fluorescence variables were measured and analyzed under 13 gradients of soil water content. Net photosynthetic rate(PN), stomatal conductance(gs), and water-use efficiency(WUE) in the seedlings exhibited a clear threshold response to the relative soil water content(RSWC). The highest PNand WUEoccurred at RSWCof51.84 and 64.10%, respectively. Both PNand WUEwere higher than the average levels at 39.79% B RSWCB 73.04%. When RSWCdecreased from 51.84 to 37.52%,PN, gs, and the intercellular CO2 concentration(Ci)markedly decreased with increasing drought stress; the corresponding stomatal limitation(Ls) substantially increased, and nonphotochemical quenching(NPQ) also tended to increase, indicating that within this range of soil water content, excessive excitation energy was dispersed from photosystem II(PSII) in the form of heat, and the reduction in PNwas primarily due to stomatal limitation.While RSWCdecreased below 37.52%, there were significant decreases in the maximal quantum yield of PSII photochemistry(Fv/Fm) and the effective quantum yield of PSII photochemistry(UPSII), photochemical quenching(qP), and NPQ; in contrast, minimal fluorescence yield of the dark-adapted state(F0) increased markedly. Thus,the major limiting factor for the PNreduction changed to a nonstomatal limitation due to PSII damage. Therefore, an RSWCof 37.52% is the maximum allowable water deficit for the normal growth of seedlings of F. suspensa, and a water content lower than this level should be avoided in field soil water management. Water contents should be maintained in the range of 39.79% B RSWCB 73.04% to ensure normal function of the photosynthetic apparatus and high levels of photosynthesis and efficiency in F.suspensa. 相似文献
18.
以东北山樱桃(Cerasus sachalinensis Kom.)实生幼苗为试材,利用Hansatch PEA,采用叶绿素荧光诱导动力学理论和JIP-test数据分析方法,研究了对-羟基苯甲酸对叶片叶绿素荧光参数的影响。结果表明:幼苗在不同浓度对-羟基苯甲酸(0.1A、1A、10A)处理下的叶片光合性能指数(PIABS)、捕获的激子将电子传递到电子传递链中QA-下游的其他电子受体的概率(Ψo)、用于电子传递的量子产额(φEo)和单位面积有活性的反应中心数目(RC/CSm)较对照均有所下降;PSⅡ最大量子效率(φPo)、单位面积有活性的反应中心数目(RC/CS0)几乎没有变化;而PSⅡ受体侧的电子受体库容量(Sm)则高于对照,且呈"上升-下降"趋势。天线色素吸收的能量(ABS/RC)在低浓度下有小幅升高,反应中心捕获的能量(TRo/RC)、用于电子传递的能量(ETo/RC)及用于热耗散的能量(DIo/RC)则无明显变化。可见,对-羟基苯甲酸对东北山樱桃叶片光合结构的不同部位产生影响,进而降低光合性能,影响光合作用。 相似文献
19.
GAO Jian PENG Zhen-hua 《林业研究》2006,17(4):269-272
Introduction Salinity is a major factor in inhibiting plant growth and decreasing forest productivity. Up to 1997, the total area affected by salinity in the world had amounted to 930 million hm2 (FAO), and is still increasing. A global study of land use … 相似文献