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1.
CO2浓度倍增对几种植物叶片的叶绿素蛋白质复合物的影响   总被引:3,自引:0,他引:3  
研究了CO_2浓度倍增对大豆(Glycine max L.,C_3植物)、黄瓜(Cucumis sativus L.,C_3植物)、谷子(Setaria italica (L.) Beauv.,一种不很典型的C_4植物)和玉米(Zea mays L.,C_4植物)叶片的叶绿素蛋白质复合物的影响。实验植物盆栽于聚乙烯薄膜(或玻璃)的开顶式培养室中。播种后对照室的CO_2浓度立即保持在大气浓度(350±10)×10~(-6)中,CO_2浓度倍增处理室则保持在(700±10)×10~(-6)下。研究结果表明,对于大豆、黄瓜和谷子,CO_2浓度倍增均使其PSⅡ捕光叶绿素a/b-蛋白质复合物(LHCⅡ)的聚合体态的量增多,单体态的量减少。但C_4植物玉米对CO_2浓度倍增没有这样的反应。作者认为在大豆等植物中,LHCⅡ的上述状态变化可能是植物的光合机构对长期高CO_2浓度的一种适应效应,这样能提高光合作用中光能的吸收、传递和转换的效率,并支持高效的光合碳素同化作用。  相似文献   

2.
研究了CO_2浓度倍增对谷子(Setaria italica (L.)Beauv.)叶片单位鲜重和单位叶面积叶绿素(Chl)和类胡萝卜素(Car)的含量以及PSⅡ功能的影响。结果表明,CO_2浓度倍增能提高拔节期成熟叶片和灌浆期成熟旗叶的Chl和Car的含量,并且能提高这两种叶片PSⅡ反应中心开放部分的比例。然而拔节期叶片和灌浆期旗叶的qN值和PSⅡ总的光化学量子产量,以及 F_v/F_o、F_v/F_m和F_d/F_s的值对CO_2浓度倍增的响应不同,表明CO_2浓度倍增对拔节期叶片光合功能的改善优于灌浆期的旗叶。  相似文献   

3.
染色体组分析及小麦族的系统学   总被引:12,自引:1,他引:11  
小麦族(Triticeae)是禾本科植物中与人类关系最为密切的一大类群,该族约有325个种,广布于世界各地。小麦族中包含着重要的粮食作物小麦(Triticum aestivum)、大麦(Hordeum vulgare)和黑麦(Secale cereale)以及一些具有重要经济价值的牧草,如:老兰麦(Elymus Sibiricus)、冰草(Agropyron cristatum)和赖草(Leymus chinensis)等等。  相似文献   

4.
选取5个二倍体小麦种为实验材料,利用数码图像显微镜处理系统、气体交换参数测定系统和叶绿素荧光动力学参数测定系统,研究了二倍体小麦种间气孔特征与光合特性的差异.结果表明,二倍体小麦种间气孔和光合特征存在较大的差异:其中S基因型(Ae.Sect.Sitopsis)的气孔长度、周长和面积最大,而其宽度、密度和气孔指数却是最小的;D基因型(Ae.Tauschii)的气孔宽度、密度和气孔指数最大,而其长度、周长和面积却是最小的;D基因型(Ae.Tauschii)的净光合速率最大,而S基因型(Ae.Sect.Sitopsis)的净光合速率最小.气孔周长与气孔面积呈显著正相关关系,而气孔密度与气孔面积呈显著负相关关系.二倍体小麦的净光合速率与气孔导度呈显著正相关关系,同时气孔限制值的变化趋势与细胞间隙CO2浓度的变化趋势相反,说明二倍体小麦的光合能力主要受气孔限制.在几个种中,乌拉尔图小麦(T.urartu)具有较高的净光合速率和气孔导度,同时细胞间隙CO2浓度最低,气孔限制值最大,在光合能力和耐光抑制方面有较明显的优势;而野生一粒小麦(T.boeoticum)则在光合能力和耐光抑制方面不存在优势.同时,乌拉尔图小麦(T.urartu)的叶绿素含量最高,而野生一粒小麦(T.boeoticum)最低,叶绿素含量可能也是造成二倍体种间光合能力差异的原因之一.  相似文献   

5.
长蠕孢一新种   总被引:1,自引:0,他引:1  
本文报告寄生于小麦(Triticum aestivum L.)上的长蠕孢一个新种——小麦生长蠕孢(Drechslera triticicola sp.nov.),其分生孢子形态,培养性状,对小麦的致病力及其寄主范围等,与已报告的寄生于小麦或禾本科植物上的长蠕孢菌明显不同。  相似文献   

6.
 通过对小麦(Triticum aestivum L.)、大豆 (Glycine max (L.) Merrill)、 油菜(Brassica napus L.)和玉米(Zea mays L.)等4种作物部分非叶器官(油菜和大豆的豆荚;小麦的外稃和玉米的苞叶)的气孔频度、气孔大小和气孔指数进行了比较研究。结果发现,上述作物非叶器官的气孔频度均较对应叶低;而气孔大小和气孔指数则变化较大。其中油菜和大豆非叶器官气孔的直径通常比对应叶大,小麦和玉米非叶器官的气孔直径则较小;大豆和油菜的非叶器官气孔指数比对应叶小,  相似文献   

7.
通过对小麦(Triticum aestivum L.)、大豆 (Glycine max (L.) Merrill)、 油菜(Brassica napus L.)和玉米(Zea mays L.)等4种作物部分非叶器官(油菜和大豆的豆荚;小麦的外稃和玉米的苞叶)的气孔频度、气孔大小和气孔指数进行了比较研究。结果发现,上述作物非叶器官的气孔频度均较对应叶低;而气孔大小和气孔指数则变化较大。其中油菜和大豆非叶器官气孔的直径通常比对应叶大,小麦和玉米非叶器官的气孔直径则较小;大豆和油菜的非叶器官气孔指数比对应叶小,  相似文献   

8.
运用冷冻切片技术,用光学显微镜对了哥王(Wikstroemia indica(L.)C.A.Mey.)叶的解剖结构进行了观察研究.结果表明,了哥王叶表现出许多旱生、阳生形态,兼具有中生特点.叶表皮由一层排列紧密形状不规则的细胞组成,细胞外壁角质膜较厚;上下表皮均无毛;气孔类型为无规则型,仅分布在下表皮且下陷,气孔密度较...  相似文献   

9.
在CO2浓度分别为350μmol·mol-1和倍增浓度(700μmol·mol-1)的两个开顶式生长室内,研究了干旱胁迫下小麦(Triticum aestivum L.)光合作用和抗氧化酶活性的变化.结果表明,CO2浓度升高显著提高了小麦的净光合速率,降低了蒸腾速率,提高了气孔阻力和水分利用效率.倍增CO2浓度明显提高了SOD、POD及CAT酶活性,增强了小麦的抗氧化保护能力和抗旱性.  相似文献   

10.
云南小麦(Triticum aestivum ssp.yunnanense King)和西藏半野生小麦(Triticum aestivum ssp.tibetanum Shao) 是我国西部地区特有的两个普通小麦(T.aestivum L.)亚种。我们采用改进的高离子强度法,提取云南小麦、西藏半野生小麦、普通小麦的两个品种(中国春和鄂恩1号)的叶绿体DNA, 并用7种限制性内切酶对它们的叶绿体DNA进行了酶切图谱分析。结果表明:在普通小麦及其两个亚种中没有叶绿体DNA的限制性片段长度差异,反映了叶绿体基因组在进化过程中相对的稳定性。 Abstract:Yunnan wheat(Triticum aestivum ssp. Yunnanense King) and Tibet semiwild wheat (Triticum aestivum ssp. Tibetanum Shao) are two endemic subspecies of common wheat (T. eastivum L.) in the west of China.Improved high ionic strength medium was adopted to extract the cpDNAs of Yunnan wheat,Tibet semiwild wheat and two cultivars of common wheat (Chinese Spring and Een 1).Restriction fragment analysis of cpDNAs was carried out with the use of 7 restriction enzymes.The results showed that there was no diversity of cpDNAs from common wheat and the two subspecies,indicating the conservatism of the chloroplast genome during the process of evolution.  相似文献   

11.
The distribution of glycine decarboxylase (GDC) in leaves of pea (Pisum sativum L.) and wheat (Triticum aestivum L.) has been investigated using immunogold labeling of the P-protein subunit of the GDC complex. Mitochondria in photosynthetic mesophyll cells were densely labeled, whereas those in nonphotosynthetic vascular parenchyma and epidermal cells were only weakly labeled. In pea leaves the density of immunogold labeling on mitochondria in the chloroplast-containing bundle sheath and stomatal guard cells was intermediate between that in mesophyll and epidermal cells. In both species the density of labeling on mitochondria in a cell appeared to reflect the photosynthetic capacity of the cell. This relationship was further examined in wheat where a natural developmental gradient exists along the lamina such that cell maturity increases with distance from the basal meristem. In this case the density of labeling on mesophyll cell mitochondria increased with photosynthetic development and with increasing maturity of the cell. Vascular cell mitochondria, however, became less densely labeled as the cells matured. The results indicate a close, positive correlation between the concentration of GDC in the mitochondria and the photosynthetic status of the host cell. This relationship is maintained effectively under the influence of both spatial (i.e. cellular differentiation across the lamina) and temporal (i.e. cellular development along the lamina) constraints.  相似文献   

12.
运用免疫金标记电镜技术研究了禾本科C3植物大麦(Hordeum vulgare L.)和C4植物玉米(Zea mays L.)叶片中Rubisoo及其活化酶(RCA)的细胞定位,结果表明:两种植物叶片解剖结构及叶绿体超微结构差别明显.在大麦叶细胞中,只有一种叶肉细胞叶绿体,Rubisoo和RCA主要分布于叶绿体的间质中.在玉米叶细胞中,存在着维管束鞘细胞和叶肉细胞两种类型叶绿体,Rubisco主要分布于鞘细胞叶绿体的基质中,但在叶肉细胞叶绿体中亦有少量特异性标记;RCA在鞘细胞叶绿体和叶肉细胞叶绿体的基质中都有分布.两种植物叶绿体结构及光合作用关键酶定位的不同,体现了C3植物和C4植物在光合器结构与功能上的差异.  相似文献   

13.
Contrasting effects on the stomatal index (SI), stomatal density,epidermal cell size and number were observed in four chalk grasslandherbs (Sanguisorba minor Scop., Lotus corniculatus L., Anthyllisvulneraria L. and Plantago media L.) following exposure to elevatedcarbon dioxide concentrations (CO2) in controlled environmentgrowth cabinets. SI of S. minor increased for both leaf surfaces,whilst in A. vulneraria and P. media SI decreased on one surfaceonly. In L. corniculatus , no differences in SI were observedas epidermal cell density changed in parallel with stomataldensity. In L. corniculatus and S. minor stomatal density increasedon both surfaces, whereas in P. media it decreased; in A. vulnerariastomatal density decreased on the abaxial leaf surface alonefollowing exposure to elevated CO2. In the latter three species,SI changed because stomatal density did not change in parallelwith epidermal cell density. The results suggest elevated CO2is either directly or indirectly affecting cell differentiationand thus stomatal initiation in the meristem. In S. minor and P. media leaf growth increased in elevated CO2,because of increased cell expansion of epidermal cells, whereasin L. corniculatus, epidermal cell size decreased and greaterleaf growth was because of an increase in epidermal cell divisions.In A. vulneraria, leaf size did not change, but increased cellexpansion on the adaxial surface suggests CO2 affects leaf surfacesdifferently, either directly or indirectly at the cell differentiationstage or as the leaf grows. These results suggest component species of a plant communitymay differ in their response to elevated CO2. Predicting theeffect of environmental change is therefore difficult.Copyright1994, 1999 Academic Press Elevated CO2, Sanguisorba minor (salad burnet), Lotus corniculatus (birdsfoot trefoil), Anthyllis vulneraria (kidney vetch), Plantago media (hoary plantain), stomatal index, stomatal density, epidermal cell size  相似文献   

14.
Responses of CO2 assimilation and stomatal conductance to decreasing leaf water potential, and to environmental factors, were analysed in a mixed natural stand of sessile oak (Quercus petraea ssp. medwediewii) and beech (Fagus svlvatica L.) in Greece during the exceptionally dry summer of 1998. Seasonal courses of leaf water potential were similar for both species, whereas mean net photosynthesis and stomatal conductance were always higher in sessile oak than in beech. The relationship between net photosynthesis and stomatal conductance was strong for both species. Sessile oak had high rates of photosynthesis even under very low leaf water potentials and high air temperatures, whereas the photosynthetic rate of beech decreased at low water potentials. Diurnal patterns were similar in both species but sessile oak had higher rates of CO2 assimilation than beech. Our results indicate that sessile oak is more tolerant of drought than beech, due, in part, to its maintenance of photosynthesis at low water potential.  相似文献   

15.
落羽杉属(杉科)叶表皮结构及气孔参数   总被引:9,自引:0,他引:9       下载免费PDF全文
落羽杉属Taxodium Rich.现生3种植物——落羽杉T. distichum (L.) Rich.、池杉T. ascendens Brongn.和墨西哥落羽杉T. mucronatum Tenore.的条形叶为双面气孔型或单面气孔型。叶片远轴面气孔分布于中脉两侧,每侧各有4-8列气孔。叶片中部气孔数量稳定,顶部和基部气孔数量比中部略少。近轴面气孔在中脉两侧各有1-4行,有时仅少数几个气孔或没有气孔分布。非气孔分布区内,表皮细胞长方形,细胞壁直或稍微呈波状,细胞长轴与叶片长轴一致。气孔分布区内的表皮细胞有时为多边形。气孔器椭圆形,长轴与叶片长轴垂直或成一定的角度。保卫细胞壁加厚明显,极端联合形成极层结构。落羽杉属3种现生植物的气孔密度和气孔指数差异显著,不同采集地的落羽杉气孔密度和气孔指数差异不显著。这3种植物的气孔指数的变异系数均小于气孔密度的变异系数,用气孔指数指示大气CO2浓度比用气孔密度可靠。  相似文献   

16.
The subcellular compartmentation of β -glucosidase was studied in rye, maize and wheat seedlings by immunocytochemical methods. For detection, we used a 10 nm gold-labeled secondary antibody, and results were observed using transmission electron microscopy. In all three species, β -glucosidase was found in plastids, cytoplasm and cell walls. In rye, gold particles were seen on cell walls and cytoplasm in epidermal cells of the root tip and shoot, in bundle sheath cells of the shoot and in all cells, except the vascular bundle cells of the coleoptile. Gold labeling was also observed in plastids of the bundle sheath cells of rye shoot tips and in cortical cells of root tips. In wheat, gold labeling was observed on cell walls and cytoplasm of epidermal cells in the shoot base and coleoptile, and on cell walls and plastids in epidermal cells of the root tip. In maize, gold labeling was mainly found in plastids or proplastids in vascular bundle cells and bundle sheath cells of the shoot, in bundle sheath cells of the coleoptile and in epidermal cells of the root. Some gold particles were also found in cell walls and cytoplasm of stomatal guard cells of the shoot base and vascular bundle cells of the shoot tip and in the cell walls of bundle sheath cells of the shoot tip and root tip epidermal cells. Results are discussed in relation to the role of β -glucosidase in hydroxamic acid release and overall defense mechanism of monocotyledons.  相似文献   

17.
The nonchromosomal stripe 2 (NCS2) mutant of maize (Zea mays L.) has a DNA rearrangement in the mitochondrial genome that segregates with the abnormal growth phenotype. Yet, the NCS2 characteristic phenotype includes striped sectors of pale-green tissue on the leaves. This suggests a chloroplast abnormality. To characterize the chloroplasts present in the mutant sectors, we examined the chloroplast structure by electron microscopy, chloroplast function by radiolabeled carbon dioxide fixation and fluorescence induction kinetics, and thylakoid protein composition by polyacrylamide gel electrophoresis. The data from these analyses suggest abnormal or prematurely arrested chloroplast development. Deleterious effects of the NCS2 mutant mitochondria upon the cells of the leaf include structural and functional alterations in the both the bundle sheath and mesophyll chloroplasts.  相似文献   

18.
The activity and intercellular distribution of sucrose-phosphate synthase (SPS; EC 2.4.1.14) were determined in fully expanded leaves from a range of C4 plants. In Zea mays L. and Atriplex spongiosa F. Muell., SPS was located almost exclusively in the mesophyll cells. In other species, SPS was found in both cell types, with the activity in the bundle sheath cells ranging from 5% of the total leaf activity in Echinochloa crus-galli (L.) Beauv. to 35% in Sorghum bicolor Moench. At the end of the light period, starch was found only in the bundle sheath cells in all of the species examined. There appears to be little correlation between C4-acid decarboxylation type and the location of sucrose and starch synthesis in the leaves of C4 plants. Received: 18 October 1996 / Accepted: 20 November 1996  相似文献   

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