Import and unloading of 14C assimilate into mature leaves of Coleus blumei

1985 ◽  
Vol 63 (10) ◽  
pp. 1700-1707 ◽  
Author(s):  
David G. Fisher ◽  
Walter Eschrich
Keyword(s):  
Shoot Tips ◽  
Mature Leaf ◽  
Mature Leaves ◽  
Coleus Blumei ◽  
Low Concentrations ◽  
Axillary Branches

Mature leaves of Coleus blumei Benth. were tested for their ability to import 14C assimilate, to unload and metabolize it, and to transfer it to the mesophyll. To enhance the potential for import, plants were preconditioned by removal of shoot tips and axillary branches, by 48 h of darkness, and by removal of roots. One mature leaf on each plant was isolated in a CO2-free chamber and kept in the light or dark while the rest of the plant was exposed for 5 h to light and 7.4 MBq 14CO2, followed by 7 h of 12CO2. Autoradiographs showed that label imported into sink leaves exposed to the light was most concentrated in the major veins, but that considerable activity also occurred in the mesophyll at the base of the lamina and adjacent to the major veins. In general, sink leaves kept in the dark imported much less label, but in one case mesophyll labeling was observed in such a leaf. Microautoradiography of sink leaf midveins indicated that 14C was always translocated in the phloem. Low concentrations of sucrose and glucose accumulated in intercostal regions of both lighted and darkened sink leaves within 12 h of plant illumination. Chromatography of intercostal areas of the sink leaves showed that the imported assimilate was unloaded and metabolized into a number of other compounds, which indicates that mature leaves of Coleus can be converted into genuine sinks.

scholarly journals Phloem mobility of Boron in two eucalypt clones

2009 ◽  
Vol 33 (6) ◽  
pp. 1695-1704 ◽  
Author(s):  
Edson Marcio Mattiello ◽  
Hugo Alberto Ruiz ◽  
Ivo Ribeiro da Silva ◽  
Jorge Eduardo Souza Sarkis ◽  
Júlio César Lima Neves ◽  
...  
Keyword(s):  
Foliar Application ◽  
Soluble Sugars ◽  
Xylem Sap ◽  
Mature Leaf ◽  
Boron Deficiency ◽  
Isotope Tracer ◽  
Mature Leaves ◽  
Productivity Losses ◽  
Leaves And Roots ◽  
B Mobility

Boron deficiency causes large productivity losses in eucalypt stands in extensive areas of the Brazilian Cerrado region, thus understanding B mobility is a key step in selecting genetic materials that will better withstand B limitation. Thus, in this study B mobility was evaluated in two eucalypt clones (68 and 129), under B sufficiency or B deficiency, after foliar application of the 10B isotope tracer to a single mature leaf. Samples of young tissue, mature leaves and roots were collected 0, 1, 5, 12 and 17 days after 10B application. The 10B:11B isotope ratio was determined by HR-ICP-MS. Samples of leaves and xylem sap were collected for the determination of soluble sugars and polyalcohols by ion chromatography. Boron was translocated within eucalypt. Translocation of foliar-applied 10B to the young tissues, mature leaves and roots was higher in clone 129 than in 68. Seventeen days after 10B application to a single mature leaf, between 14 and 18 % of B in the young tissue was originated from foliar B application. In plants with adequate B supply the element was not translocated out of the labeled leaf.

Sorbitol Versus Sucrose as Photosynthesis and Translocation Products in Developing Apricot Leaves

1985 ◽  
Vol 12 (6) ◽  
pp. 657 ◽  
Author(s):  
RL Bieleski ◽  
RJ Redgwell
Keyword(s):  
Leaf Development ◽  
Main Product ◽  
Mature Leaf ◽  
Young Leaf ◽  
Mature Leaves ◽  
Specific Transport ◽  
Young Leaves

Very young apricot leaves behave like the young leaves of most plants; that is, [14C]sucrose is formed as the main product of 14CO2 photosynthesis, and also when the leaves are supplied with [14C]glucose. [14C]sorbitol is not produced, and is poorly metabolized when fed to the leaf. Expanding leaves behave differently: [14C]sorbitol and [14C]sucrose are formed in similar amounts from both 14CO2 and [14C]glucose; and when [14C]sorbitol is supplied, it is readily metabolized and utilized for growth. Mature leaves are different again. They form [14C]sorbitol as the main product from 14CO2 and from [14C]glucose, and they do not metabolize [14C]sorbitol at all. Thus during development, apricot leaves gain but then lose the ability to utilize sorbitol. They also gain and keep the ability to synthesize sorbitol. This suggests that different biochemical paths exist for sorbitol formation and utilization, and that these paths are differently developed in the various stages of leaf development. Although the very young leaves did not synthesize sorbitol from CO2 or glucose, they contained it as their major sugar. Translocation behaviour was therefore studied. Neither the very young leaves nor the expanding leaves export any photosynthate, but the mature leaf rapidly translocates carbohydrate, mainly in the form of sorbitol, to the younger leaves as well as the rest of the plant. [14C]sorbitol supplied to the mature leaf can be recovered in that form from the very young leaf on the same shoot. This further establishes the role of sorbitol in apricot as a specific transport carbohydrate.

Import and unloading of 14C assimilate into nonphotosynthetic portions of variegated Coleus blumei leaves

1985 ◽  
Vol 63 (10) ◽  
pp. 1708-1712 ◽  
Author(s):  
David G. Fisher ◽  
Walter Eschrich
Keyword(s):  
Mature Leaves ◽  
Coleus Blumei ◽  
Intact Leaves

Variegated leaves of Coleus blumei Benth. were exposed for 4 h to 1.85 MBq 14CO2 to study the movement of 14C assimilate from green to albino portions of the lamina. Autoradiographs showed considerable 14C activity in both veins and mesophyll of the central albino regions, whether the lamina was left intact or various parts of it were severed or removed prior to 14CO2 exposure. However, when all of the photosynthetic tissue was removed, virtually no label appeared in the albino tissue. Autoradiographs of chromatographed extracts of albino regions from intact leaves showed that sucrose was the most abundant labeled compound and that imported assimilate was unloaded and metabolized into a number of other compounds. The albino region is therefore a genuine sink. No label was imported into any part of mature leaves when lower leaves were fed 14CO2, and young developing leaves ceased to import in the tip-to-base progression typical of dicotyledonous leaves.

scholarly journals Effect of Nacl in Water Cultuire on the Ion Uptake and growth of Atriplex Hastata L.

1956 ◽  
Vol 9 (1) ◽  
pp. 67 ◽  
Author(s):  
RF Black
Keyword(s):  
Dry Matter ◽  
Sea Water ◽  
Root Systems ◽  
Inorganic Anions ◽  
Mature Leaf ◽  
Ion Uptake ◽  
Tomato Plants ◽  
Mature Leaves ◽  
Donnan Equilibrium ◽  
Matter Basis

A/riplex hasia/a is taken as an example of a halophytie member of the genus. As a seedling it is shown to be tolerant to NaGI concentrations !tpproximating that of sea� water (O�tiiVI). Growth, however, is severely inhibited in concentrations above O�aM. For comparable cOllcentmtions, the chloride cOlltellts of the mature leaves are lower than those of either A. vesicaria or tomato plants. The root systems of A. has/a/a exhibit considerably higher chloride (mntents on a dry matter basis than the mature leaves. The total of the mature leaf cations analysed greatly exceeded the total of the inorganic anions. This condition is shown to agree with what would be expeeted, assuming a simple Donnan equilibrium existed between the mature leaves and the external eulture solution, where the concentration of the latter is 0'2M: or above.

scholarly journals Variation in Macronutrient Content, Phytochemical Constitution and In Vitro Antioxidant Capacity of Green and Red Butterhead Lettuce Dictated by Different Developmental Stages of Harvest Maturity

Antioxidants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 300 ◽  
Author(s):  
Christophe El-Nakhel ◽  
Antonio Pannico ◽  
Giulia Graziani ◽  
Marios C. Kyriacou ◽  
Maria Giordano ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Developmental Stages ◽  
Quinic Acid ◽  
Mature Leaf ◽  
Maturity Stage ◽  
Mature Leaves ◽  
Environment Chamber ◽  
Butterhead Lettuce ◽  
Harvest Maturity

Rising life expectancy and the demanding modern lifestyle drive the growing appeal of healthy and balanced diets centered on vegetable and fruit consumption. Functional, phytonutrient-packed and principally raw food is in high demand. Microgreens constitute such a novel functional food that combines a high sensory and bioactive value, which invites comparison to their mature-leaf counterparts. For this purpose, a controlled environment chamber experiment was carried out to compare the mineral, phytochemical and antioxidant capacity attributes of two-pigmented Lactuca sativa L. var. capitata cultivars (green and red Salanova®) harvested at the microgreens and the mature-leaf stage. Macronutrients were assessed through ion chromatography, while carotenoids and polyphenols were assessed and quantified through HPLC-DAD and UHPLC-Q-Orbitrap HRMS, respectively. Calcium and magnesium were higher in microgreens irrespective of the cultivar; conversely, phosphorous, potassium and nitrate where higher in mature leaves. All pigments including chlorophyll, lutein and β-carotene augmented at advanced maturity stage and were more concentrated in the red pigmented cultivar at both stages. Total polyphenols accumulated more densely in red Salanova, particularly in the microgreens stage; whereas, in green Salanova, the accumulation was significant but less pronounced in the mcirogreens stage. Chlorogenic acid, quercetin malonyl glucoside, rutin and coumaroyl quinic acid were the most concentrated phenolic acids in microgreens, while feruloyl tartaric acid was predominant in mature leaves. Finally, when a high carotenoids content is sought, mature lettuce leaves should be the prime culinary choice, whereas high polyphenolic content is dictated by both the cultivar and the harvest stage, with red Salanova microgreens being the most nutrient-packed choice.

scholarly journals Comparative leaf morphology and anatomy of three Asteraceae species

2006 ◽  
Vol 49 (1) ◽  
pp. 135-144 ◽  
Author(s):  
Patricia Milan ◽  
Adriana Hissae Hayashi ◽  
Beatriz Appezzato-da-Glória
Keyword(s):  
Leaf Blade ◽  
Leaf Morphology ◽  
Glandular Trichomes ◽  
Mature Leaf ◽  
Secretory Structures ◽  
Mature Leaves ◽  
Secretory Cavities ◽  
Mikania Glomerata ◽  
Secretory Ducts

The objective of this paper was to describe and compare the morphology and anatomy of mature leaves of Mikania glomerata Spreng., Porophyllum ruderale Cass. and Vernonia condensata Baker (Asteraceae) species that have different habits emphasizing their secretory structures. Longitudinal and transversal sections of mature leaf blades of the three species were analyzed at the apex, base, and medium third part of the midvein of the leaf blade and of the margin. M. glomerata had uniseriate glandular trichomes and secretory ducts; P. ruderale had hydathodes and secretory cavities; and V. condensata had idioblasts and uni-and biseriate glandular trichomes.

scholarly journals COMPARISON OF PHENOLIC ACIDS AND ANTIOXIDANT ACTIVITIES OF YOUNG AND MATURE LEAVES OF TECTONA GRANDIS L F

2018 ◽  
Vol 11 (1) ◽  
pp. 60
Author(s):  
Greeshma Murukan ◽  
Murugan K
Keyword(s):  
Phenolic Compounds ◽  
Antioxidant Capacity ◽  
Phenolic Acids ◽  
Leaf Extract ◽  
Antioxidant Activities ◽  
Tectona Grandis ◽  
Mature Leaf ◽  
Leaf Extracts ◽  
Antioxidant Power ◽  
Mature Leaves

Objective: The present study aims in comparison of phenolic acids and its antioxidant potentialities of young and mature leaf extract of Tectona grandis L f.Methods: Various phenolic acids present in methanolic leaf extract of young and mature leaves of T. grandis were analyzed by reversed-phase high-performance liquid chromatography analysis. The antioxidant potentiality of the extracts was determined by various analytical methods such as 2,2-diphenyl-1-picrylhydrazyl, ferric reducing/antioxidant power, and metal chelating activity.Results: Methanolic leaf extracts of young and mature leaf of T. grandis showed a pool of phenolic compounds such as gallic, vanillic, p-hydroxybenzoic, ferulic, chlorogenic, sinapic, p-coumarate, and cinnamic acids. Irrespective of the methods used for analyzing antioxidant capacity, young leaf extract showed potent antioxidant potentiality when compared with the mature leaf extract.Conclusion: The methanolic extract of teak leaves is rich source of many phenolic compounds, and these compounds attribute to the antioxidant capacity of the leaves. Meanwhile, by comparing the young and mature leaves, the young leaves showed much more potential than the other. It is, therefore, concluded that the young teak leaves can be used as a good source of natural antioxidant.

scholarly journals Levels of Candidatus Liberibacter asiaticus and Xanthomonas citri in Diverse Citrus Genotypes and Relevance to Potential Transmission from Pollinations

HortScience ◽  
2011 ◽  
Vol 46 (6) ◽  
pp. 854-857 ◽  
Author(s):  
E.W. Stover ◽  
T.G. McCollum
Keyword(s):  
Quantitative Polymerase Chain Reaction ◽  
Citrus Canker ◽  
Mature Leaf ◽  
Poncirus Trifoliata ◽  
Tissue Type ◽  
Sample Collection ◽  
Xanthomonas Citri ◽  
Mature Leaves ◽  
Liberibacter Asiaticus ◽  
Genotypic Group

The diseases huanglongbing [HLB, associated with Candidatus Liberibacter asiaticus (CLas)] and Asian citrus canker [ACC, caused by Xanthomonas citri (Xcc)] are widespread in Florida and many other citrus-growing areas, presenting unprecedented challenges for citrus breeding. Because HLB and ACC weaken trees and compromise cropping, breeding is much less efficient using seed parents that have been exposed to these diseases. Therefore, it would be highly desirable to use unique disease-exposed selections only as pollen parents with pollen applied to disease-free trees. However, there may be a risk of introducing these diseases using such pollen sources. To assess this potential, abundance of the pathogens associated with these diseases was assessed in anthers and flowers using quantitative polymerase chain reaction. Because CLas is systemic, levels on mature leaves from the flower source trees were assessed to see if the presence of CLas in flowers was associated with leaf levels. Disease-exposed trees were tested in 10 genotypes from each of three broad genotypic categories, which reflect different levels of susceptibility to the diseases associated with the pathogens studied: Poncirus trifoliata hybrids (most resistant to HLB), Citrus maxima and hybrids (susceptible to both diseases), and C. reticulata and hybrids (considerable resistance to ACC). Of the 30 samples of each tissue type analyzed for CLas, 88% of mature leaves, 69% of flowers, and 88% of anthers had one or more CLas bacterium per sample. The trifoliate genotypic group had significantly lower levels of CLas than the pummelo and mandarin groups in mature leaf samples, but CLas levels were more similar between groups in anther and flower samples, and the pathogen was present in most of the trifoliate hybrids tested. Mean numbers of CLas detected per nanogram nucleic acid were 100 to 800 times higher in mature leaf samples, most characteristic of HLB symptoms, compared with anther samples. Xcc DNA was detected in 30% of flower samples and 23% of anther samples. No significant differences in Xcc levels were found between tissue type or genotypic group. However, regressions between Xcc levels in flowers and percent of plant pedigree derived from mandarin had a negative correlation and an r2 of 0.159 (P = 0.029). The biology of CLas is consistent with the pathogen being present in anthers from unopened flowers, whereas the ACC pathogen detected inside flowers was likely the result of contamination despite great care in sample collection and handling. Where exceptional diligence to exclude HLB and ACC is appropriate, results suggest that there may be a risk of spreading these pathogens through use of pollen from trees on infected farms.

scholarly journals COMPARISON OF PHENOLIC ACIDS AND ANTIOXIDANT ACTIVITIES OF YOUNG AND MATURE LEAVES OF TECTONA GRANDIS L F

2018 ◽  
Vol 11 (1) ◽  
pp. 60 ◽  
Author(s):  
Greeshma Murukan ◽  
Murugan K
Keyword(s):  
Phenolic Compounds ◽  
Antioxidant Capacity ◽  
Phenolic Acids ◽  
Leaf Extract ◽  
Antioxidant Activities ◽  
Tectona Grandis ◽  
Mature Leaf ◽  
Leaf Extracts ◽  
Antioxidant Power ◽  
Mature Leaves

Objective: The present study aims in comparison of phenolic acids and its antioxidant potentialities of young and mature leaf extract of Tectona grandis L f.Methods: Various phenolic acids present in methanolic leaf extract of young and mature leaves of T. grandis were analyzed by reversed-phase high-performance liquid chromatography analysis. The antioxidant potentiality of the extracts was determined by various analytical methods such as 2,2-diphenyl-1-picrylhydrazyl, ferric reducing/antioxidant power, and metal chelating activity.Results: Methanolic leaf extracts of young and mature leaf of T. grandis showed a pool of phenolic compounds such as gallic, vanillic, p-hydroxybenzoic, ferulic, chlorogenic, sinapic, p-coumarate, and cinnamic acids. Irrespective of the methods used for analyzing antioxidant capacity, young leaf extract showed potent antioxidant potentiality when compared with the mature leaf extract.Conclusion: The methanolic extract of teak leaves is rich source of many phenolic compounds, and these compounds attribute to the antioxidant capacity of the leaves. Meanwhile, by comparing the young and mature leaves, the young leaves showed much more potential than the other. It is, therefore, concluded that the young teak leaves can be used as a good source of natural antioxidant.

GENOTYPIC DIFFERENCES IN DARK RESPIRATION OF MATURE LEAVES IN WINTER WHEAT (Triticum aestivum L.)

1988 ◽  
Vol 68 (3) ◽  
pp. 669-675 ◽  
Author(s):  
M. WINZELER ◽  
D. E. McCULLOUGH ◽  
L. A. HUNT
Keyword(s):  
Triticum Aestivum ◽  
Winter Wheat ◽  
Leaf Size ◽  
Dry Weight ◽  
Triticum Aestivum L ◽  
Mature Leaf ◽  
Genotypic Differences ◽  
Leaf Respiration ◽  
Mature Leaves ◽  
Respiration Rates

Oxygen uptake of mature leaves was measured on a range of winter wheat (Triticum aestivum L.) genotypes both indoors (four genotypes) and in the field (six genotypes). The relationship among mature leaf respiration, leaf size, specific leaf weight and leaf nutrient status was investigated. Correlations between leaf respiration and total plant dry weight as well as tiller number were calculated in the indoor study. Significant differences of 6–25% in mature leaf respiration rates were evident among winter wheat genotypes in the indoor as well as in the field study. Leaf position as well as environment had a marked influence on the order and magnitude of genotype effects on mature leaf respiration rates. Leaf respiration was not related to specific leaf weight, leaf nitrogen, or phosphorus content, but was negatively related to leaf size. Leaf respiration was not related to total dry weight and tiller number of single plants grown indoors.Key words: Respiration, genotypic differences, wheat (winter), Triticum aestivum L.

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