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1.
Kutík J. Holá D. Vičánková A. Šmídová M. Kočová M. Körnerová M. Kubínová L. 《Photosynthetica》2001,39(4):497-506
Differences in ultrastructural parameters of mesophyll cell (MC) chloroplasts, contents of photosynthetic pigments, and photochemical activities of isolated MC chloroplasts were studied in the basal, middle, and apical part of mature or senescing leaf blade of two maize genotypes. A distinct heterogeneity of leaf blade was observed both for structural and functional characteristics of chloroplasts. In both mature and senescing leaves the shape of MC chloroplasts changed from flat one in basal part of leaf to nearly spherical one in leaf apex. The volume density of granal thylakoids decreased from leaf base to apex in both types of leaves examined, while the amount of intergranal thylakoids increased in mature leaves but decreased in senescing leaves. The most striking heterogeneity was found for the quantity of plastoglobuli, which strongly increased with the increasing distance from leaf base. The differences in chloroplast ultrastructure were accompanied by differences in other photosynthetic characteristics. The Hill reaction activity and activity of photosystem 1 of isolated MC chloroplasts decreased from leaf base to apex in mature leaves. Apical part of senescing leaf blade was characterised by low contents of chlorophyll (Chl) a and Chl b, whereas in mature leaves, the content of Chls as well as the content of total carotenoids (Car) slightly increased from basal to apical leaf part. This was reflected also in the ratio Chl (a+b)/total Car; the ratio of Chl a/b did not significantly differ between individual parts of leaf blade. Both genotypes examined differed in the character of developmental gradient observed along whole length of leaf blade. 相似文献
2.
Tissue Distribution of Glutamate Synthase and Glutamine Synthetase in Rice Leaves : Occurrence of NADH-Dependent Glutamate Synthase Protein and Activity in the Unexpanded, Nongreen Leaf Blades 总被引:3,自引:2,他引:1
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To further explore the function of NADH-dependent glutamate synthase (GOGAT), the tissue distribution of NADH-GOGAT protein and activity was investigated in rice (Oryza sativa L.) leaves. The distributions of ferredoxin (Fd)-dependent GOGAT, plastidic glutamine synthetase, and cytosolic glutamine synthetase proteins were also determined in the same tissues. High levels of NADH-GOGAT protein (33.1 μg protein/g fresh weight) and activity were detected in the 10th leaf blade before emergence. The unexpanded, nongreen portion of the 9th leaf blade contained more than 50% of the NADH-GOGAT protein and activity per gram fresh weight when compared with the 10th leaf. The expanding, green portion of the 9th leaf blade outside of the sheath contained a slightly lower abundance of NADH-GOGAT protein than the nongreen portion of the 9th blade on a fresh weight basis. The fully expanded leaf blades at positions lower than the 9th leaf had decreased NADH-GOGAT levels as a function of increasing age, and the oldest, 5th blade contained only 4% of the NADH-GOGAT protein compared with the youngest 10th leaf blade. Fd-GOGAT protein, on the other hand, was the major form of GOGAT in the green tissues, and the highest amount of Fd-GOGAT protein (111 μg protein/g fresh weight) was detected in the 7th leaf blade. In the nongreen 10th leaf blade, the content of Fd-GOGAT protein was approximately 7% of that found in the 7th leaf blade. In addition, the content of NADH-GOGAT protein in the 10th leaf blade was about 4 times higher than that of Fd-GOGAT protein. The content of plastidic glutamine synthetase polypeptide was also the highest in the 7th leaf blade (429 μg/g fresh weight) and lowest in nongreen blades and sheaths. On the other hand, the relative abundance of the cytosolic glutamine synthetase polypeptide was the highest in the oldest leaf blade, decreasing to 10 to 20% of that value in young, nongreen leaves. These results suggest that NADH-GOGAT is important for the synthesis of glutamate from the glutamine that is transported from senescing source tissues through the phloem in the nongreen sink tissues in rice leaves. 相似文献
3.
We tested the possible cytokinin effect on the functioning of the active transport system involved in the assimilate loading into the phloem as a cause for the cytokinin sink and retention effect. This effect is manifested in the deceleration of substance export from and the stimulation of substance import to the sites of local phytohormone application to the mature detached leaf from untreated leaf areas. To affect the membrane mechanisms of the substance transport, we used leaf treatment with the phytotoxin fusicoccin, an enhancer of plasmalemmal H+-ATPase and a potential stimulator of assimilates export, and with the phytohormone ABA affecting transport, metabolism, and plant growth. However, fusicoccin did not enhance 14C-sucrose export from the leaf blade and did not interfere with the cytokinin-induced export deceleration. ABA reduced substantially 14C export from the leaf but eliminated the cytokinin effect on this process. Similar results were obtained for broad bean (Vicia faba L.) leaves with apoplastic phloem loading, involving H+-ATPase activity, and pumpkin (Cucurbita pepo L.) leaves with symplastic phloem loading, that is, occurring without sucrose transmembrane translocation and without H+-ATPase involvement. The conclusion is that the cytokinin-induced development of sink zones in source leaves is not related to the membrane mechanisms of the substance transport in the mesophyll–phloem system. The data obtained support the idea that the cause for the cytokinin sink and retention effect is the enhancement of elongation growth and total activation of metabolism in the mesophyll cells of the detached leaf. 相似文献
4.
甘蔗组织中游离氨基酸组分和含量研究 总被引:1,自引:0,他引:1
在甘蔗幼苗中,各个器官的丙氨酸含量都比较高,但在完全展开叶的叶片和叶鞘中丝氨酸含量更高;游离氨基酸总量的分布为完全展开叶叶片》完全展开叶叶鞘,苗根>心叶、幼茎,在伸长盛期和工艺成熟前期9个甘蔗基因型+1叶均以丙氨酸占优势。不同基因型的各种游离氨基酸含量都有明显的差异。在工艺成熟前期,早熟基因型的游离氨基酸总量比较低。伸长盛期与工艺成熟前期游离氨基酸总量之比值也与不同基因型的熟性密切相关,中晚熟品种的明显较低.早熟品种的较高,三个细茎早熟原种材料的更高。 相似文献
5.
The objective of this study was to assess genotypic variation in soybean chlorophyll (Chl) content and composition, and to
test if these data could be used as a rapid screening method to predict genotypic variation in leaf tissue N content. Chl
contents and composition were examined among 833 soybean (Glycine max L. Merr.) accessions and related to SPAD meter readings and leaf N content. In the initial year of the study (2002), the
relationship between leaf Chl and leaf N contents (r
2 = 0.043) was not sufficiently close for Chl to be useful as a predictive tool for leaf N content. Therefore, leaf N content
was not determined in 2004 but samples were again collected for determination of Chl content and composition. In 2002, the
soybean accessions separated into two distinct groups according to leaf Chl a/b ratios, with the majority of a mean ratio of 3.79. However, approximately 7 % (60) of the genotypes could be readily assigned
to a group with a mean Chl a/b ratio of 2.67. Chl a/b analyses in 2004 confirmed the results obtained in 2002 and of 202 genotypes, all but 6 fell into the same group as in 2002. 相似文献
6.
Reproductive stages of 5 japonica, 9 indica, and 2 javanica cultivars of rice ( Oryza sativa L.) were provided to compare the contents of protein for cytosolic glutamine synthetase (GS1; EC 6.3.1.2) in the lowest position of the attached leaf blade (position 6 from the primary leaf) and those for NADH-glutamate synthase (NADH-GOGAT; EC 1.4.1.14) in non-green portion of the expanding 10th leaf blade. Some of the indica cultivars, including Kasalath, contained GS1 protein twice as high as other japonica and javanica cultivars based on total leaf nitrogen. Most of the indica cultivars, on the other hand, contained less NADH-GOGAT protein than japonica and javanica cultivars. Immunostaining proved that GS1 protein was located in vascular tissues of the leaf blades of Kasalath, which was identical to our previous results with a japonica cultivar [Sakurai et al. (1996) Planta 200: 306–311]. Although relative contents of GS1 protein in the leaf blade of Kasalath increased as a function of leaf age, GS1 activity remained relatively constant. In addition, Kasalath showed lower activity than other japonica and javanica cultivars, especially during leaf expansion. GS1 activity, based on GS1 protein amount, changed during the life span of the leaf blade and we thus assume that GS1 activity was modulated post-translationally in rice leaves. 相似文献
7.
Isolation of an Antibacterial Substance from Mahonia fortunei and its Biological Activity against Xanthomonas oryzae pv. oryzicola 总被引:1,自引:0,他引:1
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Gaoqing Yuan Yuanyuan Chen Fangjing Li Rongjin Zhou Qiqin Li Wei Lin Lihong Huang 《Journal of Phytopathology》2017,165(5):289-296
This study aimed to isolate the antibacterial substance from Mahonia fortunei and determine its antibacterial activity against Xanthomonas oryzae pv. oryzicola (Xoc). Bacterial leaf streak of rice, caused by Xoc, is an important rice disease and difficult to control. During a screening of antibacterial plants against plant pathogenic bacteria at an early stage, the extract from M. fortunei was found to have a strong inhibitory effect on Xoc. In this study, the chemical components of M. fortunei stems were extracted using methanol solvent, the antibacterial substance was isolated and purified by liquid–liquid partition and silica gel column chromatography and its structure was identified by nuclear magnetic resonance. The effect and mode of action of the antibacterial substance on bacterial leaf streak of rice were also detected under greenhouse conditions. Two compounds were identified, berberine and jatrorrhizine, which had a strong inhibitory effect on Xoc. The antibacterial activity of berberine was stronger, with a half‐maximal inhibitory concentration (IC50) of 2.9008 mg/l. At the concentration of 0.5 g/l, its control efficacy on bacterial leaf streak of rice was more than 84%. Additionally, berberine could be absorbed by rice leaves and be translocated up and down in the rice plant, and the effective period was long, but its capability of lateral translocation inside the blade was poor. 相似文献
8.
A field experiment was conducted with two cassava cultivars and eight levels of nitrogen to examine the relationship between
extractable chlorophyll (Chl) content of cassava leaves and both the Chl meter value (SPAD) and leaf colour chart (LCC) score.
The SPAD, LCC, and Chl a+b content were influenced by leaf position, growth stage, cultivar (cv.), and N fertilization. The cvs. and N fertilization
had significant effect on SPAD, LCC, and Chl a+b content of youngest fully expanded leaf (leaf 1) blade in most cases. An F-test indicated that common equations pooled across
cvs., N fertilization, and growth stages could be used to describe the relationships between Chl a+b content and LCC and between SPAD and LCC, but not between SPAD and Chl a+b content. Relationships between tuber yield and SPAD, LCC, and Chl a+b content were significant (p<0.05) and positive at 30 and 60 d after planting. Thus LCC and SPAD can be used to estimate leaf Chl content which is an
indicator of leaf N status. 相似文献
9.
水杨酸对不同灌水下限青花菜生理特性及产量品质的影响 总被引:1,自引:0,他引:1
以青花菜为试材,采用大田试验研究了0.15mmol/L水杨酸(SA)对不同灌水下限(75%、60%和45%土壤相对含水量)青花菜生理特性及产量品质的影响。结果显示:(1)随灌水下限的降低,青花菜叶片相对含水量、水势及叶绿素含量均呈下降趋势,而其叶片电解质渗透率以及游离脯氨酸(Pro)、丙二醛(MDA)、可溶性蛋白(Pr)含量逐渐升高;青花菜的花球重及维生素C含量(Vc)随灌水下限的降低而降低,相反硝酸盐含量及可溶性固形物含量随之升高。(2)叶面喷施0.15mmol/L SA显著提高了青花菜叶片相对含水量、水势、渗透调节物质含量、产量及品质,且降低了膜脂过氧化产物MDA含量,其中以45%灌水下限处理效果最为显著,60%灌水下限处理次之,75%灌水下限处理最小。研究认为,适宜浓度外源SA通过改善青花菜叶片水分生理状况,提高叶片渗透调节物质含量,降低质膜透性来增强其对干旱胁迫的抗性,且以60%灌水下限配合叶面喷施0.15mmol/L SA处理较佳。 相似文献
10.
The growth of primordia of marginal buds (marginals) which differentiate on leaf margins is correlatively inhibited on intactBryophyllum crenatum plants. Following leaf isolation, the marginals are released from this correlative inhibition, which process is
accompanied within 2 to 10 h after leaf isolation with a decrease in the content of endogenous IAA in the leaf blade. This
decrease can be enhanced by transversal cutting of the leaf blade into three parts which also results in enhanced subsequent
growth of the marginals. The growth which follows after the release of the marginals from correlative inhibition is accompanied
in cut leaf blades with an increased content of endogenous IAA in the period from 12 h to 7 d after leaf isolation when compared
with uncut leaf blades. The highest content of endogenous IAA was recorded in the middle section, and the lowest IAA content
in the basal section of the leaf blade. 相似文献
11.
The dominant Knotted-1 mutations in maize alter development of the leaf blade. Sporadic patches of localized growth, or knots, and fringes of ectopic ligule occur along lateral veins of mutant leaf blades. In addition, bundle sheaths do not completely encircle lateral veins on mutant leaf blades. We have compared mutant leaf blades with wild-type leaves to determine the precise nature of the perturbed regions. Our analysis includes characterization of epidermal cell shapes, localization of photosynthetic proteins and histology of the leaf. We show that mutant leaf blades are a mosaic of leaf organ components. Affected regions of mutant leaf blades resemble either sheath or auricle tissue in both external and internal features. This conversion of blade cells represents an acropetal shift of more basal parts of the leaf blade region and correlates with previously identified ectopic expression of the Knotted-1 protein in the leaf blade. We propose that inappropriate expression of Kn1 interferes with the process of establishment of cell identities, resulting in early termination of the normal blade development program or precocious expression of the sheath and auricle development programs. © 1994 Wiley-Liss, Inc. 相似文献
12.
In this paper we show the effect of leaf tissue sampling on estimation of β-glucuronidase activity. Pieces of leaves taken
from Agrobacterium-mediated transformed T0 plants of cauliflower were sampled and the GUS activity was measured fluorometrically. Whole leaf tissue and samples of small
pieces representing various leaf zones were compared. A great variation of GUS activity within leaf was observed, for which
coefficient of variation reached up to 70%. The GUS activity was nearly symmetrical for the left and right side of a leaf
blade, with the highest values along the top and middle parts of a leaf blade edge. The relible and repeatable estimation
of GUS activity was obtained only if a whole leaf tissue, except the midrib, was used, which allow to reduce the variation
to about 10%. 相似文献
13.
橡胶树(Heveabrasiliensis)种子催芽生长一般使用沙床培育,沙子是不可再生资源,为了选择一种适合橡胶树种子培育方式来替代对沙子的依赖,该研究通过水培、悬空培育和传统的沙培比较橡胶树实生苗第1蓬叶稳定时,苗木的生长势、生理指标及养分含量。结果表明,水培实生苗地上部株高、茎粗、叶面积的长势最佳,壮苗指数和生物量的含量最高,但其根太长,根相对较细。水培的叶、茎、根的可溶性糖、丙二醛、游离脯氨酸、超氧化物歧化酶的含量均较低;水培和悬空培育的叶片和茎的叶绿素、类胡萝卜素及根系活力的含量没有显著性差异,均高于沙培。水培的叶、茎、根中的氮和磷含量最低,沙培的最高;而水培实生苗根和茎中钾的含量较高,叶片中含量与悬空培育、沙培均没有显著性差异;悬空培育在叶、茎、根中钾的含量最低。水培促进了苗木的生长,降低干旱胁迫,提高养分利用率,但后续还需调控根系,建设良好根团。悬空培育的苗木长势较弱,还需进一步完善方法。 相似文献
14.
Kusumi Kensuke Hirotsuka Shoko Shimada Hiroshi Chono Yoko Matsuda Osamu Iba Koh 《Journal of plant research》2010,123(4):617-622
Chloroplast biogenesis is most significant during the changes in cellular organization associated with leaf development in
higher plants. To examine the physiological relationship between developing chloroplasts and host leaf cells during early
leaf development, we investigated changes in the carbon and nitrogen contents in leaves at the P4 developmental stage of rice,
during which leaf blade structure is established and early events of chloroplast differentiation occur. During the P4 stage,
carbon content on a dry mass basis remained constant, whereas the nitrogen content decreased by 30%. Among carbohydrates,
sucrose and starch accumulated to high levels early in the P4 stage, and glucose, fructose and cellulose degradation increased
during the mid-to-late P4 stage. In the chloroplast-deficient leaves of the virescent-1 mutant of rice, however, the carbon and nitrogen contents, as well as the C/N ratio during the P4 stage, were largely unaffected.
These observations suggest that developing rice leaves function as sink organs at the P4 stage, and that chloroplast biogenesis
and carbon and nitrogen metabolism in the leaf cell is regulated independently at this stage. 相似文献
15.
Dessislava Todorova Irina Vaseva-Gemisheva Petar Petrov Ekaterina Stoynova-Bakalova Vera Alexieva Emanuil Karanov Aileen Smith Michael Hall 《Acta Physiologiae Plantarum》2006,28(6):613-617
The specific activity of cytokinin oxidase/dehydrogenase (EC 1.5.99.12) (CKX) was determined in leaves of wild type (wt) and ethylene-insensitive mutant (eti5) of Arabidopsis thaliana (L.) Heynh plants. Comparative studies showed that this mutation has lower basal CKX activity than wt. Application of 4PU-30 (N1-(2-chloro-4-pyridyl)-N2-phenylurea) resulted in decreased CKX activity in both wt and mutant plants. The treatment increased leaf blade thickness and the volume of chlorophyll-containing cells per unit leaf
area in wt but these changes were not observed in the eti5 mutant. The reduction in chlorophyll “a” and “b”, as well as in carotenoids content in the treated wt tissues resulting from altered leaf morphology was not detected in eti5 plants. 相似文献
16.
江苏引种黄连副产物的生物碱含量测定 总被引:1,自引:0,他引:1
利用薄层扫描法和高效液相色谱法测定了江苏引种黄连根茎以外的副产物(须极、连渣、叶片、叶柄)中生物碱的含量,其中4年生黄连叶片生物碱含量达2.43%,叶柄达3.75%,6年一黄连须根生物碱含理达5.67%,连渣达6.32%,建议充分利用须根、连渣、叶片、叶柄等副产物。 相似文献
17.
S. Seneweera 《Photosynthetica》2011,49(1):145-148
Net photosynthetic rate (P
N) measured at elevated CO2 concentration (C
e), ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), and nitrogen (N) content in rice leaves decreased significantly
after exposure to long term C
e. The reduction in P
N, Rubisco, and leaf N at C
e was similar for the last fully expanded leaf blade (LFELB) and expanding leaf blade (ELB). Spatial leaf N content in the
ELB was highest in the zone of cell division, sharply declined as cell expansion progressed and gradually increased with cell
maturation. Maximum reduction in spatial leaf N and Rubisco content was found at C
e only within cell expansion and maturation zones. The spatial leaf N content correlated well with the amount of Rubisco synthesized
during leaf expansion, suggesting that N deposition into the expanding leaf blade may be the key for Rubisco synthesis and
possibly photosynthetic acclimation to C
e. 相似文献
18.
In isolated leaves ofBryophylluni crenatum the intensity of marginal bud formation decreases from the apex towards the blade base, which is associated with the decreasing
content of enioganous gibberallins. As proved by Dostál (1930), the formation of marginal buds on transversely divided blade
of the isolated leaf increases in comparison with the non-divided control leaf. The results of our experiments have revealed
that the increase in the formation of marginal buds in the blade transversely divided into the apical, middle and basal parts
is connected with the increasing level of endogenous gibberellins, especially in the apical part. This rising level appears
as early as 7 days following blade division,i.e. at the time preceding the formation of marginal bud bases.
InBryophyllum crenatum plants the level of endogenous cytokinins was estimated in apical, middle and basal leaves, as well as in adjacent internodia.
Maximum content was found out in the leaves from the middle stem part, which is probably associated with the capacity of this
part to form marginal buds spontaneously also in intact plants. However, prior to flowering the maximum of cytokinin activity
is shifted to the apical stem part. 相似文献
19.
为揭示海拔梯度对苦竹林立竹叶片碳(C)、氮(N)、磷(P)化学计量特征的影响,该文以3个海拔梯度[低海拔,(200±10) m;中海拔,(400±10) m;高海拔,(800±10) m]苦竹林为研究对象,测定1至3年生立竹叶片C、N、P含量,分析其化学计量特征和异速增长关系。结果表明:(1)立竹年龄对苦竹叶片C、N、P含量及其化学计量特征影响明显,随立竹年龄的增大,苦竹叶片C、N、P含量和N∶P总体上均呈降低趋势,而C∶N、C∶P总体上呈升高趋势。(2)海拔对苦竹叶片C、N、P含量及其化学计量特征有重要影响,随海拔梯度升高,不同年龄立竹叶片C含量呈先升高后下降变化趋势,N、P含量总体上呈降低趋势,而C∶N、C∶P和N∶P均呈升高趋势。(3)不同海拔梯度苦竹林立竹叶片C、N、P含量和C∶N、C∶P差异显著,中、高海拔苦竹林立竹叶片N∶P无显著差异,均显著高于低海拔苦竹林;不同海拔梯度苦竹林立竹叶片C、N、P间呈显著的正异速增长关系,随海拔梯度的升高,C-N、C-P异速增长指数显著升高,而N-P异速增长指数显著下降。综上结果表明,高海拔苦竹林虽然N、P利用效率提高,但立竹叶片C含量较低,P限制性作用增强;中海拔苦竹林不但具有较高的N、P利用效率,而且立竹叶片C含量高,说明中海拔是苦竹林丰产培育的适宜海拔。 相似文献
20.
大黄属3种大黄植物不同部分蒽醌含量的测定与比较 总被引:7,自引:0,他引:7
采用C18反相柱高效液相色谱方法分离、外标法定量对大黄属掌叶组唐古特大黄、波叶组波叶大黄、穗序组穗序大黄的根(及根茎)、叶片、叶柄、主茎四部分的芦荟大黄素、大黄酸、大黄素、大黄酚4种游离和结合蒽醌的含量进行了测定和比较。结果表明:唐古特大黄中,叶片中的游离蒽醌含量高于其它部分,游离蒽醌总量地上部分远高于地下部分;结合蒽醌则根中最高,蒽醌总量地下部分远高于地上部分。波叶大黄和穗序大黄中,游离和结合蒽醌均为根中最高,穗序大黄蒽醌总量地下部分远高于地上部分,而波叶大黄中,游离蒽醌总量地上部分高于地下部分,结合蒽醌总量地上部分与地下部分相差不大,地上部分略高于地下部分。 相似文献