三种愈伤组织中质体的DNA含量变化及其与水稻花粉白苗形成的关系

以质体为单位的愈伤组织ptDNA的荧光强度变化显示出了特有的规律性,结合光培养花粉白苗叶质体结构的电镜观察及叶绿素等色素的测定等,这种规律性似提示花粉白苗的ptDNA由于发生了相继缺失而显示出高度异质性,花粉白苗的形成则在于其占优势ptDNA的严重缺失,花粉白苗ptDNA的这种相继缺失不是随机的,似反映了ptDNA顺序组织上的特点,故ptDNA发生缺失的潜在可能性具有普遍意义,它与父系细胞质体类核的消失存在着并行关系,花粉白苗的占优势ptDNA指导的植株的性状,而次要ptDNA亦在较小程度上显示出影响。     

水稻花粉白苗的若干特性及其成因的探讨

水稻花粉白苗的再分化所生成的再生植株全为白苗,这说明花粉白苗的形成是不可逆的,可能是基因突变的结果。不同品种或杂交组合的水稻花粉白苗叶片丙酮提取液的吸收光谱相互间显示出了相似性,这种相似性就进而提示突变可能发生在基因组的特定位点上。有可能花粉白苗是质体DNA在花粉的脱分化过程中发生缺失形成的。这种缺失主要影响质体rRNA的合成水平,并不导致蛋白质和叶绿素合成能力的全面丧失。花粉植株细胞中的质体可能是不均一的。     

生长素吲哚乙酸对铜绿微囊藻生理生化及产毒特性的影响

为了探究生长素吲哚乙酸(IAA)对产毒铜绿微囊藻(Microcystis aeruginosa)的影响, 从生长、光合色素含量、叶绿素光诱导荧光特征、脂质氧化和微囊藻毒素合成特性等方面, 研究了IAA对M. aeruginosa CHAB6301生理生化及产毒的影响。结果表明, 在低浓度IAA(0.04和0.2 mg/L)条件下, 铜绿微囊藻生长、叶绿素含量、光合系统(PSⅡ)电子传递效率及藻毒素含量均无明显变化, 藻蓝蛋白、别藻蓝蛋白和丙二醛(MDA)含量均低于对照。高浓度IAA(1和5 mg/L)能够促进细胞生长, 提高叶绿素含量, 但是抑制藻蓝蛋白和别藻蓝蛋白含量, 降低膜脂过氧化程度和细胞内藻毒素合成。综合各指标测定结果, 低浓度IAA对M. aeruginosa CHAB6301生长和光合作用影响不明显, 而高浓度IAA可促进藻细胞生长和光合作用, 增加微囊藻水华形成几率。     

银杏叶萜内酯含量的变化及其与叶绿素荧光特性的关系

为探究银杏(Ginkgo biloba)叶萜类内酯含量和光合同化作用的关系,对其内酯含量和叶绿素荧光特性进行了研究。结果表明,不同采收时间银杏叶中白果内酯和银杏内酯含量有显著差异,总体上,5月份含量较低,此后逐渐升高,8月份达到高峰,然后快速下降,10月底最低;与此同时,银杏叶片的光合色素以及叶绿素荧光参数也呈现周期性变化。白果内酯以及萜内酯含量与叶绿素荧光参数Y(NPQ)之间呈极显著正相关关系,因此,可以通过银杏叶片的叶绿素荧光参数预测白果内酯和萜内酯含量。     

Photosynthetic pigment contents in twigs of 24 woody species assessed by in vivo reflectance spectroscopy indicate low chlorophyll levels but high carotenoid/chlorophyll ratios

We have examined whether spectral reflectance indices used to non-destructively assess photosynthetic pigment levels and their ratios in leaves, could also be used for the same purpose in peridermal twigs. Regression lines of selected indices versus actual pigment levels, obtained from leaves and twigs of five species, suggested that semi-quantitative assessments are safe, provided that twig periderms could be easily removed. Given that, we proceeded to our next objective of screening a large number of species (24), in order to characterize their photosynthetic pigment profiles. Index comparisons between twigs and corresponding leaves indicated that twigs are characterized by lower levels of total chlorophyll and, unexpectedly, higher carotenoid/chlorophyll ratios. Moreover, the exposed and shaded sides of twigs displayed similar values for both indices in 80% of the species, suggesting that shade may not be the only factor shaping pigment levels and ratios. We discuss our results arguing that the distinct microenvironment within a twig may pose additional needs to the photosynthetic machinery, necessitating elevated carotenoid/chlorophyll ratios.     

Short-term pigment changes in Norway spruce needles

The photosynthetic pigment contents and the chlorophyll fluorescence induction in Norway spruce [ Picea abies (L.) Karst.] needles were monitored at 3 h intervals over a 10 day period. This covered 6 days of high insolation, one day of low insolation, followed by three more days of high insolation. During the first six days only small changes in mean pigment contents were observed but we interpret them as suggesting a daily rhythm in total chlorophyll content with two maxima and minima. The day of low insolation was paralleled by larger pigment changes, mostly an increase in chlorophyll b along with a decrease in carotenoid content. With the resumption of high insolation, pigments gradually return to their previous levels. During the entire period chlorophyll a fluorescence induction remained relatively constant. These short-term responses may reflect features of thylakoid organization in relation to pigment content and suggest possible long-term adaptive mechanisms in non deciduous conifers.     

不同成熟度对烤后烟叶中质体色素及其降解产物的影响

研究了不同成熟度河南南阳烤烟烟叶中质体色素及其降解产物含量变化的结果表明：（1）烟叶中叶绿素a、叶绿素b、总叶绿素和类胡萝卜素的含量随成熟度的提高呈下降趋势。（2）未熟到成熟的南阳烟区中部叶中,叶绿素降解产物新植二烯含量逐渐下降,成熟时最低,之后又有回升的趋势;类胡萝卜素降解产物含量的变化随成熟度的进度呈现不同的变化规律。     

Genetic variability associated with photosynthetic pigment concentration, and photochemical and nonphotochemical quenching, in strains of the cyanobacterium Microcystis aeruginosa

Although populations of cyanobacteria are usually considered to be clonal, their capacity to survive environmental changes suggests intrapopulation genetic variation. We therefore estimated the genetic variability on the basis of two processes important for any photoautotroph - photochemical and nonphotochemical quenching - as well as photosynthetic pigment concentrations. For this purpose, two parameters related to photochemical and nonphotochemical quenching were measured using specific experimental and statistical procedures, in 25 strains of the cyanobacterium Microcystis aeruginosa, along with their contents of chlorophyll a, total carotenoids and phycocyanin. The experimental procedure allowed discrimination between genetic and nongenetic (or residual) variability among strains. The high genetic variability found in photosynthetic pigments and both photosynthetic parameters denotes large differences even among strains isolated from the same community. The high genetic diversity within a population could be important for the evolutionary success of cyanobacteria.     

FACE条件下大气O3浓度增高对小麦剑叶光合色素含量的影响

应用FACE研究平台,采用烟农19、扬麦16、嘉兴002、扬麦15和扬辐麦2号等5个小麦品种,以O3自然浓度为对照,研究了大气O3浓度增高50％对不同小麦品种剑叶光合色素含量的影响.结果表明:开放式大气O3浓度增高条件下,小麦剑叶叶绿素a(Chl a)、叶绿素b(Chl b)、叶绿素总量Chl(a+b)和类胡萝卜素含量在孕穗期和开花期与对照差异不显著,而花后各时期均不同程度的降低,其中,Chl a、Chl b和Chl(a+b)含量下降达显著水平,说明大气O3浓度增高对叶绿素合成影响较小,但加速了其衰降过程.不同品种小麦剑叶光合色素含量对大气O3浓度增高的反应存在基因型差异,扬麦15和嘉兴002对大气O3浓度增高的敏感性弱于扬麦16、扬辐麦2号和烟农19.在籽粒灌浆盛期(花后21 d左右),剑叶Chl a、Chl b和Chl(a+b)含量与千粒重呈显著正相关.     

水稻、小麦花药培养白化苗质体亚显微结构和蛋白质的研究

通过对小麦和水稻花药培养白化苗质体的电镜观察,表明白化苗质体早期发育正常,但没有观察到正常的成熟叶绿体。对白化苗质体的类囊体膜蛋白的分析表明,它缺乏细胞核编码的chla/b AP_2,质体DNA编码的chla AP_2和chla AP_3。质体DNA编码的ATPasc的α、β亚基显示了分子量和含量的变化。色素蛋白质的分析表明在白化苗质体中有两种小分子置的色素蛋白存在。文章还对产生上述结果的原因进行了讨论。     

FACE条件下大气O3浓度增高对小麦剑叶光合色素含量的影响

应用FACE研究平台,采用烟农19、扬麦16、嘉兴002、扬麦15和扬辐麦2号等5个小麦品种,以O₃自然浓度为对照,研究了大气O₃浓度增高50%对不同小麦品种剑叶光合色素含量的影响.结果表明：开放式大气O₃浓度增高条件下,小麦剑叶叶绿素a (Chl a)、叶绿素b (Chl b)、叶绿素总量Chl(a+b)和类胡萝卜素含量在孕穗期和开花期与对照差异不显著,而花后各时期均不同程度的降低,其中,Chl a、Chl b和Chl(a+b)含量下降达显著水平,说明大气O₃浓度增高对叶绿素合成影响较小,但加速了其衰降过程.不同品种小麦剑叶光合色素含量对大气O₃浓度增高的反应存在基因型差异,扬麦15和嘉兴002对大气O₃浓度增高的敏感性弱于扬麦16、扬辐麦2号和烟农19.在籽粒灌浆盛期(花后21 d左右),剑叶Chl a、Chl b和Chl(a+b)含量与千粒重呈显著正相关.     

互花米草与芦苇光合色素含量对淹水措施的响应

以上海崇明东滩入侵植物互花米草与本地种芦苇为研究对象,研究持续淹水胁迫对两种植物光合色素含量的影响.结果表明：互花米草与芦苇叶片的光合色素基本组成与含量不同,对持续淹水的响应也不同.在持续淹水胁迫下,互花米草叶绿素a、叶绿素b及类胡萝卜素含量降低,叶绿素a／b、类胡萝卜素／叶绿素值提高;芦苇各色素含量升高,叶绿素a／b、类胡萝卜素/叶绿素值基本保持稳定.解除持续淹水胁迫后,互花米草各色素含量逐渐升高,叶绿素a／b、类胡萝卜素／叶绿素值降低,并逐渐接近对照水平;而芦苇各色素含量显著高于对照.两种植物均表现出一定的补偿效应,但芦苇比互花米草更能适应同等程度的持续淹水胁迫.应用持续淹水措施治理互花米草时,可采用本地种芦苇作为治理后湿地恢复的替代植物.     

Pigment Content of Selected Planktonic Algae in Response to Simulated Natural Light Fluctuations and a Short Photoperiod

The lipophilic photosynthetic pigments in Limnothrix redekei, Planktothrix agardhii (cyanobacteria), Stephanodiscus minutulus, Synedra acus (diatoms), Scenedesmus acuminatus, and Scenedesmus armatus (chlorophycean) all isolated from an eutrophic lake were quantitatively determined by HPLC. The algae were grown semi-continuously under nutrient sufficient conditions at 20°C at a 12/12 h light/dark cycle with constant irradiance or with simulated natural light fluctuations as well as at a 6/18 h light/dark cycle with constant irradiance, all at the same daily light exposure. The zeaxanthin and the myxoxanthophyll contents of cyanobacteria were not influenced by fluctuating light, a short photoperiod or a different sampling time. The chlorophyll b/a ratio, the lutein/chlorophyll a ratio, and the neoxanthin content of chlorophycean as well as the chlorophyll c/a and the fucoxanthin/chlorophyll a ratio of diatoms were only slightly influenced by these factors. Therefore in some cases marker pigment contents and in other cases marker pigment/chlorophyll a ratios may be more useful for quantifying the relative importance of different taxonomic groups in natural phytoplankton. Simulated natural light fluctuations or the length of the photoperiod only slightly influenced the pigment content or the marker pigment/chlorophyll a ratio.     

枫香秋季变色期叶色变化及其生理基础

为探究秋季枫叶呈色的关键生理因素,该文以转色期叶色为绿色、黄色和红色的枫香单株为试材,研究了L^*、a^*、b^*值变化与叶片色素、可溶性糖及可溶性蛋白质含量变化的相关性。结果表明:(1)在变色期,3种色彩枫香叶片叶绿素a、叶绿素b、总叶绿素和类胡萝卜素均大量降解,花色素苷不同程度积累。(2)绿色叶单株叶绿素和类胡萝卜素始终保持较高含量,花色素苷含量上升4.2倍,叶片内色素含量比值始终保持稳定; 黄色叶单株叶绿素和类胡萝卜素含量最低,花色素苷含量上升4.4倍,b^*值与叶绿素含量极显著负相关,与类胡萝卜素含量显著负相关,与花色素苷/类胡萝卜素含量比值极显著正相关; 红色叶单株叶绿素和类胡萝卜素含量略高于黄色叶单株,花色素苷含量上升27.2倍,a^*值与叶绿素含量、类胡萝卜素含量极显著负相关,与花色素苷含量显著正相关,与色素含量比值无显著相关性。(3)红色叶单株具有较高的可溶性糖含量和可溶性蛋白质含量。因此,在枫香叶片变色期,保持较高的叶绿素和类胡萝卜素含量,维持色素含量比值稳定使叶片呈现绿色; 叶绿素和类胡萝卜素的大量降解,以及花色素苷/类胡萝卜素含量比值的升高使叶片呈现黄色; 叶绿素的降解和花色素苷的大量合成使叶片呈现红色。     

Possible correlation between high temperature-induced floret sterility and endogenous levels of IAA,GAs and ABA in rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.)

In order to explore the possible physiological mechanism of high temperature induced sterility in rice, we examined the floret sterility and endogenous plant growth regulator contents in pollens of two hybrid rice cultivars Shanyou63 and Teyou559 that are tolerant and susceptible to high temperature, respectively. Indexes of floret sterility, pollen activity, and variation of endogenous indole-3-acetic acid (IAA), gibberellic acids (GAs), abscisic acid (ABA), free proline and soluble proteins in anthers were measured. We found that during the course of high temperature treatment, both cultivars exhibited a marked decrease in pollen activity, pollen germination and floret fertility; however, the high temperature tolerant Shanyou63 showed a much slower rate of decrease than the high temperature susceptible Teyou559. In addition, anthers of both cultivars displayed a decrease in the contents of IAA, GAs, free proline and soluble proteins but an increase in the ABA content. Yet compared to Teyou559, Shanyou63 retained significantly higher levels of free praline and GAs and a lower level of ABA, along with higher pollen vigour and pollen germination rate even after prolonged high temperature treatment. Our study suggests a possible correlation between pollen viability/floret sterility and high temperature-caused changes in IAA, GAs, ABA, free proline and soluble protein contents. The severity in these changes may reflect the variation of rice cultivars in their heat stress sensitivities for floret development.     

Isolation and identification of protochlorophylls obtained by oxidation of corresponding chlorophylls

Protochlorophyll with a high yield is isolated under oxidation of chlorophyll a by tetrachloro-o-quinone. A pigment, designated as protochlorophyll b, is isolated by the same way from chlorophyll b. A method of purification of the pigments obtained is worked out, their properties are studied and their structures are identified. The proposed method can be recommended for isolation of protochlorophyll a and b.     

Pollen–pistil relationships and pollen size-number trade-off in species of the tribe Lycieae (Solanaceae)

Pollen volume may be involved in different associations with other floral traits. Particularly, the literature indicates that pollen volume can be implicated in a functional relationship with pistil length, and that it may be affected by a trade-off with pollen number because of the subdivision of limited resources. To assess these associations, pollen volume was subjected to correlation analyses with pollen number and pistil length in 20 Argentinean and Chilean taxa of the monophyletic tribe Lycieae. Depending on the mechanisms operating on pollen size and number, the variability of these traits may be different. Therefore, their coefficients of variation were compared. Pistil length and pollen volume showed a strong positive correlation. In contrast, pollen grain size and number were significantly correlated at neither inter- nor intraspecific levels. Results suggest that pollen size and pistil length may co-evolve. The central role of this interaction is discussed. The lack of a correlated variation in pollen size and number may be related to the similar constraints experienced by the species and/or because constraints are operating at the plant level and not at the species level. Lower variance in pollen size compared with pollen number denotes that pollen size may be the main trait subjected to natural selection. Electronic Publication     

遮荫对半夏叶片光合色素与保护酶活性的影响

对半夏进行不同程度遮荫处理,研究了其生长过程中叶组织的光合色素含量、叶绿素a/b值、保护酶体系(SOD、POD、CAT)活性和丙二醛(MDA)含量的变化及其生理特性.结果表明:不同处理的半夏在生长过程中,光合色素的含量呈先升后降的趋势;与全光照相比,遮荫处理的叶绿素含量较高,叶绿素a/b值较低,类胡萝卜素含量在生长发育中早期较低而后期较高;SOD、POD、CAT活性呈由低到高再降低的趋势,MDA含量持续升高;遮荫处理的SOD、POD活性和MDA含量均低于全光照处理,CAT活性则表现为先高于后低于全光照处理.适度的遮荫可以提高半夏叶绿素的含量,降低膜系统受到的伤害,改善半夏的倒苗状况,为半夏叶片的生长提供较好的环境.     

自然条件下滤减UV-B辐射对烤烟光合色素含量的影响

在自然环境中,以烟草栽培品种K326为材料,通过覆盖不同透明薄膜滤减UV—B辐射,研究100％（CK）、75％（T1）、50％（T2）、35％（T3）UV—B辐射透过率处理下,不同强度UV—B辐射对烟草光合色素含量的影响。结果表明：烤烟三类光合色素对UV—B辐射有不同响应。类胡萝卜素对UV—B辐射响应较敏感。成熟初期,类胡萝卜素含量与UV—B辐射强度变化具有较好的正相关性,而chl a和chl b含量基本与UV—B辐射强度呈反向变化关系。成熟后期,由于UV—B辐射累积效应,光合色素含量变化没有明显规律。现蕾期至成熟采烤烟初期,chl a：chl b与UV—B辐射的反向变化关系较明显,后期则无明显规律,其含量的下降与UV—B辐射的累积效应有关。     

滤减UV B辐射对烟叶可溶性蛋白、〖HJ*3〗〖HJ*2〗光合色素和类黄酮的影响

在云南玉溪烟区种植烤烟海拔最高(1806.0m)的通海县,通过盆栽烤烟K326试验,研究了在滤减自然的太阳UV-B辐射强度25%、50%和65%条件下,UV-B辐射对烟叶发育过程中可溶性蛋白、光合色素和类黄酮的影响。结果表明:随叶龄增加,可溶性蛋白含量下降,光合色素降解,类黄酮在老叶中积累,蛋白质在生理成熟期对UV-B辐射最敏感。与对照相比,减弱UV-B辐射处理降低了烟叶类黄酮和可溶性蛋白含量,但光合色素含量上升;较低的UV-B辐射降低了叶绿素的降解速度。结果从一侧面说明UV-B辐射对烟叶蛋白质的合成是有益的,类黄酮和叶绿素的变化是对UV-B辐射变化的适应性反应,类黄酮与蛋白质之间可能存在一定的偶联关系。