THE BIOSYNTHESIS OF INDOLEACETIC ACID IN MELAMPSORA LINI (PERS.) LEV.

1962 ◽  
Vol 40 (2) ◽  
pp. 309-315 ◽  
Author(s):  
B. I. Sahai Srivastava ◽  
Michael Shaw
Keyword(s):  
Incubation Medium ◽  
Plant Material ◽  
Indoleacetic Acid ◽  
Extension Growth ◽  
Tissue Cultures ◽  
Melampsora Lini ◽  
Solvent Systems

Mycelium of Melampsora was grown on flax cotyledons in tissue cultures. Mycelium and uredospores were incubated with DL-tryptophane-2-C14 and uredospores were incubated with L-tryptophane. Acid and neutral ether-soluble and aqueous fractions of the plant material and incubation medium were chromatographed and sprayed with chromogenic agents or radioautographed. Radioactive indoleacetic acid was produced in small amounts by both mycelium and spores (yield = 0.016% in 8 hours). The auxin was identified on the basis of its Rf values in two solvent systems, its reactions with Ehrlich and Salkowski reagents, and its ability to promote extension growth of Avena coleoptiles. Evidence for the formation of indoleacetaldehyde was also obtained. Several other radioactive and Ehrlich-positive products of tryptophane metabolism were detected but not identified. One of these could have been indolepyruvic acid. Tryptamine and indoleacetonitrile were not found. The results suggest that, in Melampsora, the synthesis of indoleacetic acid from tryptophane proceeds through indolepyruvic acid and indoleacetaldehyde.

The radial distribution and metabolism of IAA-14C in Pinus echinata stems in relation to wood formation

1974 ◽  
Vol 52 (6) ◽  
pp. 1349-1355 ◽  
Author(s):  
Lawrence E. Nix ◽  
Tomasz J. Wodzicki
Keyword(s):  
Radial Distribution ◽  
Indoleacetic Acid ◽  
Methanol Extract ◽  
Growing Season ◽  
Wood Formation ◽  
Pinus Echinata ◽  
Aqueous Fraction ◽  
Seasonal Transition ◽  
Methanolic Extracts ◽  
Solvent Systems

Radial distribution of auxin in differentiating xylem tissues was studied in decapitated 8- to 14-year-old Pinus echinata stems to which indoleacetic acid (IAA-14C) in lanolin paste was applied during early and late growing season. Small segments of the treated stems were sectioned tangentially with a sliding microtome, the serial sections were collected, and the radioactivity of each section was measured. The results indicate that IAA is radially distributed in the differentiating tissues along a steep gradient from the cambial region to the differentiating xylem and that this distribution varies during the growing season in relation to the seasonal transition to latewood formation in intact trees.Forty-five to 60% of the radioactivity recovered in methanolic extracts of the differentiating xylem after a 2-day labeling period was in the form of IAA. After 7 days 10–15% of the radioactivity recovered was in the form of IAA. The radioactivity recovered separated into ether and aqueous fractions when the methanol extract was reduced, acidified, and partitioned with ether. Chromatography of aliquots of both fractions in several solvent systems revealed no individually significant metabolite of IAA. The aqueous fraction derivatives accumulated in the tissue, and later in the season the metabolism of IAA and the accumulation of the aqueous fraction apparently decreased. In experiments where excised differentiating xylem was incubated with a liquid medium containing IAA-14C, the conversion of radioactivity to the aqueous fraction was twofold greater in early season than in late season. The significance of the results is discussed with possible relation to the control of the seasonal transition to latewood formation in conifers.

Saprophytic development of the flax rust Melampsora lini, race No. 3

1969 ◽  
Vol 47 (5) ◽  
pp. 821-823 ◽  
Author(s):  
Franziska L. M. Turel
Keyword(s):  
Yeast Extract ◽  
Spore Production ◽  
Small Cells ◽  
Inorganic Salts ◽  
Tissue Cultures ◽  
Growth And Survival ◽  
Extract Concentration ◽  
Melampsora Lini ◽  
Aerial Hyphae ◽  
Chelated Iron

A medium containing 0.1% yeast extract (Difco) in addition to sucrose, inorganic salts, and chelated iron supported saprophytic growth of Melampsora lini (Pers.) Lév., race No. 3. Cultures were started with sterile uredospores from rust-infected flax tissue cultures and were maintained for over 5 months through up to eight transfers. In some aging parts of living mycelial cultures, single one-celled teliospores were formed on aerial hyphae, and in other parts composed of dense masses of firm, small cells, clusters of uredospore-like structures were found. Growth and survival of mycelium were better when 4% sucrose was used instead of glucose, and when 500 mg/l of K2HPO4 was present in addition to the routinely used potassium monophosphate. Spore production was increased by raising the yeast extract concentration to 0.2%.

The cultivation of rust fungi upon artificial media

1974 ◽  
Vol 52 (4) ◽  
pp. 767-772 ◽  
Author(s):  
Frederick T. Wolf
Keyword(s):  
Hydrolytic Enzymes ◽  
Rust Fungi ◽  
Puccinia Graminis ◽  
Tissue Cultures ◽  
Melampsora Lini ◽  
Obligate Parasites ◽  
Pure Cultures ◽  
Physiological And Biochemical ◽  
Host Tissues ◽  
Puccinia Malvacearum

While the rust fungi have long been regarded as obligate parasites, within recent years nine species belonging to four different genera have been grown in pure culture in the laboratory. Gymnosporangium juniperi-virginianae and Uromyces caladii have been isolated from tissue cultures of their infected hosts. A culture of Puccinia malvacearum originated from a teliospore, promycelium, or basidiospore. Puccinia graminis tritici, P. graminis avenae, P. recondita trilici, P. helianthi, Melampsora lini, and Uromyces dianthi have been isolated from germinating uredospores. Melampsora lini has also been isolated through treatment of infected host tissues with hydrolytic enzymes. Some of the cytological, physiological, and biochemical findings resulting from studies of these pure cultures are discussed.

A developmental study of the stamens in a male-sterile tobacco hybrid

1977 ◽  
Vol 55 (16) ◽  
pp. 2234-2244 ◽  
Author(s):  
G. S. Hicks ◽  
J. Bell ◽  
S. A. Sand
Keyword(s):  
Sex Determination ◽  
Plant Material ◽  
Histological Study ◽  
Extension Growth ◽  
Developmental Study ◽  
Male Sterile ◽  
Stamen Primordia ◽  
Sporogenous Tissue ◽  
Nicotiana Debneyi ◽  
Tobacco Hybrid

The ontogeny of the feminized stamens in a male-sterile tobacco hybrid has been studied. Plant material 1A was derived from an initial cross between Nicotiana debneyi as female and N. tabacum cv. Kupchunos as male. All 1A flowers exhibit stigmatoid anthers at anthesis and are sterile. This teratism is cytoplasmically inherited. In a developmental series of 1A floral buds, it was found that 1A stamen primordia diverge relatively early from the normal stamen shape and appear as spatulate organ rudiments lacking differentiation into anther and filament. In 1A buds after carpel fusion and as the normal stigma is differentiating, stamens form a distinctly stigmatoid tip subtended by a short filament bearing the initials of lateral outgrowths. The stigmatoid tip then enlarges to a green, bulbous recurved structure and there is considerable extension growth of the filament. Histological study of developing and mature teratological stamens showed complete absence of sporogenous tissue and also confirmed the true stigmatic nature of the tip region. The results are discussed in relation to regulation of sex determination.

NEW EVIDENCE FOR THE PRESENCE OF INDOLEACETIC ACID IN TOBACCO

1963 ◽  
Vol 41 (5) ◽  
pp. 681-684 ◽  
Author(s):  
J. C. Sirois
Keyword(s):  
Indoleacetic Acid ◽  
Leaf Extracts ◽  
Avena Coleoptile ◽  
Nicotiana Tabacum L ◽  
Activity Curve ◽  
Coleoptile Elongation ◽  
Solvent Systems ◽  
Growth Promoting ◽  
New Evidence ◽  
Tobacco Growth

An acidic growth-promoting substance, active in the Avena coleoptile elongation test, was extracted from Resistant Havana 211 cultivar of Nicotiana tabacum L. This substance cochromatographed with indoleacetic acid (IAA) in three different solvent systems used singly, or in combination in two-direction chromatography. Its concentration–activity curve was also identical with that of IAA.Refinements in the purification procedure and the use of N,N-dimethylaminocinnamaldehyde as a spray reagent for the tobacco leaf extracts have made it possible to obtain a typical IAA color reaction at the Rf value of the tobacco growth-promoting substance. These results led to the conclusion that the auxin extracted from the tobacco tissues was IAA.

AN INDOLEACETIC ACID 'OXIDASE' SYSTEM IN THE MYCELIUM OF MELAMPSORA LINI (PERS.) LEV.

1960 ◽  
Vol 38 (5) ◽  
pp. 761-767 ◽  
Author(s):  
Ann Oaks ◽  
Michael Shaw
Keyword(s):  
Oxygen Uptake ◽  
Oxidase Activity ◽  
Indoleacetic Acid ◽  
Acid Oxidase ◽  
Oxidase System ◽  
Melampsora Lini ◽  
Host Parasite Interactions ◽  
Indoleacetic Acid Oxidase ◽  
Host Parasite

Flax rust mycelium was grown on cotyledons of flax in a modified Knop's medium. The mycelium produced and apparently secreted a typical peroxidase-mediated indoleacetic acid 'oxidase'. Decarboxylation of radioactive indoleacetate (—C14OOH) was stimulated by Mn++ (10−4 and 10−3M), dichlorophenol (10−4M), and resorcinol (10−4M). Catechol (10−4M) and pyrogallol (10−4M) inhibited the reaction. Moreover, pyrogallol competitively inhibited the reaction in the presence of resorcinol. All four phenols increased oxygen uptake by the mycelium, catechol and pyrogallol being the most effective. Cu++ (10−3M) inhibited the reaction by 60%; cyanide (10−3M) and diethydithiocarbamate (2 × 10−4M) were almost completely inhibitory. The results are discussed briefly in relation to host–parasite interactions and the control of indoleacetic acid oxidase activity in vivo.

Comparison of Choriocarcinoma and Normal Placenta

1971 ◽  
Vol 29 ◽  
pp. 324-325
Author(s):  
John C. Garancis ◽  
Roland A. Pattillo ◽  
Robert O. Hussa ◽  
Jon V. Straumfjord
Keyword(s):  
Cell Lines ◽  
Small Cells ◽  
Tissue Cultures ◽  
Glycogen Depletion ◽  
Cell Surfaces ◽  
Intercellular Spaces ◽  
Concomitant Increase ◽  
Gestational Choriocarcinoma ◽  
Cytoplasmic Glycogen ◽  
Normal Placenta

Two different cell lines (Be-Wo and Jar) of human gestational choriocarcinoma have been maintained in continuous tissue culture for a period of four and two years respectively without losing the ability to elaborate human chorionic gonadotropin (HCG). Tissue cultures, as revealed by electron microscopy, consisted of small cells with single nuclei. In some instances cell surfaces were provided with microvilli but more often the intercellular spaces were narrow and bridged by desmosomes. However, syncytium was not formed. Endoplasmic reticulum (ER) was poorly developed in both cell lines, except in some Be-Wo cells it was prominent. Golgi complex, lysosomes and numerous free ribosomes, as well as excessive cytoplasmic glycogen, were present in all cells (Fig. 1). Glycogen depletion and concomitant increase of ER were observed in many cells following a single dose of 10 ugm/ml of adrenalin added to medium (Fig. 2).

Freeze-Fracture Studies of Membranes in Developing Sieve Elements in a Plant Tissue Culture

1980 ◽  
Vol 38 ◽  
pp. 636-637
Author(s):  
R. D. Sjolund ◽  
C. Y. Shih
Keyword(s):  
Plant Tissue ◽  
Cultured Cells ◽  
Freeze Fracture ◽  
Tissue Cultures ◽  
Sieve Elements ◽  
Intact Plants ◽  
Plant Tissue Cultures ◽  
Whole Plants ◽  
Energy Dependent ◽  
Similar Elements

The differentiation of phloem in plant tissue cultures offers a unique opportunity to study the development and structure of sieve elements in a manner that avoids the injury responses associated with the processing of similar elements in intact plants. Short segments of sieve elements formed in tissue cultures can be fixed intact while the longer strands occuring in whole plants must be cut into shorter lengths before processing. While iyuch controversy surrounds the question of phloem function in tissue cultures , sieve elements formed in these cultured cells are structurally similar to those of Intact plants. We are particullarly Interested In the structure of the plasma membrane and the peripheral ER in these cells because of their possible role in the energy-dependent active transport of sucrose into the sieve elements.

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