Différenciation in vitro et de novo d'organes floraux directement a partir des couches minces de cellules de type epidermique de Nicotiana tabacum. Etude au niveau cellulaire

1974 ◽  
Vol 52 (11) ◽  
pp. 2319-2322 ◽  
Author(s):  
Nguyen Thi Dien ◽  
M. Tran Thanh Van
Keyword(s):  
Nicotiana Tabacum ◽  
Mitotic Activity ◽  
Cell Walls ◽  
De Novo ◽  
Tritiated Thymidine ◽  
Flower Buds ◽  
Floral Organs ◽  
Epidermal Tissue

Floral organs (sepals, petals, stamens, carpels) have formed de novo and directly from explants composed of 3 to 6 layers of epidermal and subepidermal cells; these organs originated from the subepidermal layer. The first symptoms of the resumption of mitotic activity included incorporation of tritiated thymidine at the level of the subepidermal layer followed by new cell walls observed after 24 h of culturing. On the average, organogenesis from cells derived from the subepidermal layer was completed after about 10 days.This work demonstrates that the epidermal tissue can form flower buds de novo and directly. [Translated by the journal]

Inducing organ generation in vitro: sepal–petal structures from tobacco flower buds

1982 ◽  
Vol 60 (6) ◽  
pp. 845-849 ◽  
Author(s):  
Alan McHughen
Keyword(s):  
Nicotiana Tabacum ◽  
Floral Organ ◽  
Defined Medium ◽  
Variable Number ◽  
Growth Substances ◽  
Flower Buds ◽  
Regulatory Systems ◽  
Nicotiana Tabacum L ◽  
Normal Manner

Tobacco (Nicotiana tabacum L. cv. Wisconsin 38) floral buds with sepal primordia only will continue organ production in a normal manner when excised from the plant and placed on the surface of a simple defined medium lacking growth substances. Such a medium is said to be developmentally inert because it does not induce or direct developmental events in the explant but does permit completion of developmental instructions, if any, carried in the explant. If the medium is supplemented with 10.0 ppm kinetin the bud produces a large but variable number of structures having some characteristics of sepals and some characteristics of petals and then continues with the initiation of fairly normal stamens and then carpels. This paper describes these structures and discusses the effect of kinetin on the regulatory systems controlling floral organ generation.

Flower bud and root neoformation in thin cell layers of Nicotiana tabacum var. Samsun: a statistical analysis of spatial and temporal changes in mitotic activity

1990 ◽  
Vol 68 (11) ◽  
pp. 2501-2508 ◽  
Author(s):  
G. Mersch ◽  
C. Nassogne ◽  
A. Havelange
Keyword(s):  
Statistical Analysis ◽  
Nicotiana Tabacum ◽  
Mitotic Activity ◽  
Temporal Changes ◽  
Flower Bud ◽  
Time Intervals ◽  
Thin Cell Layers ◽  
Spatial And Temporal Changes ◽  
Cell Layers

Our aim was to analyse comparatively the spatial and temporal changes in mitotic activity in tobacco thin cell layers cultured in vitro during the expression of two organogenetic programs, namely the flower bud and root programs. These biological materials were found to be so complex and heterogeneous that we had to rely on sophisticated statistical models for the planned study. Using these models we could detect differences not only between the two programs, but also within each program between different time intervals and, in the flower bud program, between different longitudinal segments of the thin cell layers. Key words: Nicotiana tabacum, flower bud, root, statistical analysis, mitotic activity.

The Effect of Porfiromycin on the Life Cycle of Hep-2 Cells In Vitro

1967 ◽  
Vol 53 (6) ◽  
pp. 517-521 ◽  
Author(s):  
Rose J. Papac
Keyword(s):  
Cell Cycle ◽  
Life Cycle ◽  
Mitotic Activity ◽  
Tritiated Thymidine ◽  
Predominant Effect

The effect of porfiromycin (N-methyl mitomycin) on the cell cycle in HEP-2 cells was investigated by pulse labeling with tritiated thymidine at various intervals following 4-hours incubation with the drug. Arrest of cells during the G2 phase was the predominant effect with temporary suppression of mitotic activity as well.

Organogenèse induite in vitro sur des fragments de racine de Nicotiana tabacum L.

1978 ◽  
Vol 56 (19) ◽  
pp. 2370-2374 ◽  
Author(s):  
Trinh T. Hanh
Keyword(s):  
Nicotiana Tabacum ◽  
De Novo ◽  
Single Type ◽  
Root Explants ◽  
Nicotiana Tabacum L

Explants taken from superficial epidermic and subepidermic tissues from flowering stocks of Nicotiana tabacum can be induced to flower, produce buds, callus, or roots from a single type of cell, of subepidermic origin. Explants from neoformed roots, when cultivated on media inducing the formation of flowers (IAA 10−6 M, kinetin 10−6 M), buds (IAA 10−6 M, BA 10−5 M), callus (2,4-D 5∙10−6 M, kinetin 10−7 M), and roots (IBA 10−5 M, kinetin 10−7 M) can form buds or callus. New roots are formed when either IAA or kinetin is omitted from the flowering medium. None of the above media induced the formation of flowers from root explants.Temperatures of 22 or 24 °C and the addition of 10−6 M BA were optimal for the de novo formation of buds from root explants. [Traduit par le journal]

Einfluß der Glucose auf die [14C] Thymidin-Einbaurate von Ehrlich-Ascitescarcinomzellen in vitro

1969 ◽  
Vol 08 (02) ◽  
pp. 196-206 ◽  
Author(s):  
Dieter. Kummer
Keyword(s):  
De Novo

ZusammenfassungIn nahezu glucosefreier Suspension von Ehrlich-Ascitescarcinomzellen bewirkt die Zufuhr von Glucose 2,5 × 10–4 bis 10–2 M:1. Hemmung der [14C] Thymidin-Einbaurate in die Zellen.2. Aktivierung des Ribonucleotid-Reductase-Systems und damit Stimulierung der Desoxyribonucleotidsynthese (auch der Thymidintriphosphat-de-novo-Synthese).3. Blockierung der Thymidinkinase über Endprodukthemmung, wodurch die Minderung des [14C] Thymidin-Einbaus in die Zellen erklärbar ist.

Особенности морфогенеза редкого вида Allium neriniflorum (Herb.) Backer в условиях in vitro

2019 ◽  
pp. 37-41 ◽  
Author(s):  
Альбина Шамсуновна Ахметова ◽  
Альфия Ануровна Зарипова
Keyword(s):  
De Novo

Показана возможность эффективного применения метода культуры тканей для размножения Allium neriniflorum (Herb.) Backer. Исследуемый вид является декоративным растением, размножение которого затруднено из-за низкой всхожести семян и ослабленной способности к формированию дочерних луковиц. Разработана технология клонального микроразмножения из стерильных луковиц. В качестве исходного материала использовали семена A. neriniflorum. Подобраны условия стерилизации, позволяющие достичь максимального числа (75 %) жизнеспособных эксплантов. Поверхностную стерилизацию проводили в ламинар-боксе с использованием в качестве стерилизующего агента 0,1 % раствор диацида. Семена сначала обрабатывали 70 % этанолом, затем стерилизующим раствором. Экспозиция стерилизующих растворов составляла от 5 до 9 мин. Показано, что способность к индуцированному морфогенезу существенно зависит от состава питательной среды. Максимальное число луковиц образовывалось на среде QL — 9 шт./эксплант. Исследуемые виды обладали высокой способностью к мультипликации и формированию полноценных растений при подобранных условиях культивирования in vitro. Выявленная морфогенетическая активность зачаточного побега, сегментов чешуй и донца стерильной луковицы A. neriniflorum, проявляющаяся в способности регенерировать побеги de novo, что возможно только в культуре in vitro, обеспечивает формирование полноценных луковиц. Луковицы, полученные in vitro, включали в последующие циклы микроразмножения. Культура тканей и органов in vitro позволяет размножать A. neriniflorum с более высоким коэффициентом размножения. От одной стерильной луковицы можно получить до 7000 луковиц в год. При традиционном вегетативном способе размножения материнская луковица формирует 1, редко 2 дочерние луковицы.

Methods of experimental polyploidization and their use in apple breeding

2020 ◽  
Vol 62 ◽  
pp. 85-90
Author(s):  
L. V. Tashmatova ◽  
O. V. Matsneva ◽  
T. M. Khromova ◽  
V. V. Shakhov
Keyword(s):  
Exposure Time ◽  
Cell Walls ◽  
Prolonged Exposure ◽  
Ornamental Plants ◽  
Colchicine Treatment ◽  
Apple Trees ◽  
Open Ground ◽  
High Concentrations ◽  
Diploid Gametes

The article presents methods of experimental polyploidy of fruit, berry and ornamental plants. The purpose of this review is to highlight the problems and prospects of polyploidization of plants in the open ground and in vitro culture and the possibility of their application for apple trees. For the purpose of obtaining apple tetraploids as donors of diploid gametes, seed seedlings were treated with a solution of colchicine in concentrations of 0.1-0.4 % for 24 and 48 hours. Colchicine concentrations of 0.3 % and 0.4 % at 48 hours of treatment had a detrimental eff ect on their development. As a result, tetraploids and chimeras were obtained from seeds from free pollination of the varieties Orlik, Svezhest, Kandil Orlovsky, as well as from seeds obtained from crossing the varieties Svezhest×Bolotovskoe, Moskovskoe Оzherel’e×Imrus, Girlyanda×Venyaminovskoe. The optimal concentration of colchicine was 0.1 %. Methods of colchicine treatment have been studied: 1) adding to the nutrient medium, colchicine concentration: 0.01%, 0.02%, exposure time 24h-19 days; 2) applying amitotic solution to the growth point, colchicine concentration: 0.1 %, 0.2 %, exposure time 24h-7 days. To increase the penetration of colchicine through the cell walls, a 0.1 % dimexide solution was used. Studies have shown that high concentrations and prolonged exposure to colchicine reduce the viability of explants.

Study of Phosphocalcic Glasses from SiO2-CaO-P2O5 System with and Without Silver II. The bioactivity analysis by FTIR, SEM methods and microbiological study of silver-doped glasses

2017 ◽  
Vol 68 (6) ◽  
pp. 1188-1192
Author(s):  
Daniela Avram ◽  
Nicolae Angelescu ◽  
Dan Nicolae Ungureanu ◽  
Ionica Ionita ◽  
Iulian Bancuta ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Body Fluid ◽  
Pathogenic Bacteria ◽  
De Novo ◽  
Microbiological Examination ◽  
Doped Glasses ◽  
P2o5 System ◽  
Scanning Electron

The study in vitro of the glass powders bioactivity was performed by soaking them in simulated body fluid for 3 to 21 days at a temperature of 37�C and pH = 7.20. The synthesis de novo of hydroxyapatite, post soaking was confirmed by Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The study of the antimicrobial activity was performed by microbiological examination on two strains of pathogenic bacteria involved in postoperative nosocomial infections.

Antifungal Proteins from Plant Latex

2020 ◽  
Vol 21 (5) ◽  
pp. 497-506
Author(s):  
Mayck Silva Barbosa ◽  
Bruna da Silva Souza ◽  
Ana Clara Silva Sales ◽  
Jhoana D’arc Lopes de Sousa ◽  
Francisca Dayane Soares da Silva ◽  
...  
Keyword(s):  
Cell Walls ◽  
Defense Mechanisms ◽  
Hydrolytic Enzymes ◽  
Fungal Species ◽  
Biologically Active ◽  
Protein Classification ◽  
Fungal Cell ◽  
Antifungal Proteins ◽  
Plant Latex

Latex, a milky fluid found in several plants, is widely used for many purposes, and its proteins have been investigated by researchers. Many studies have shown that latex produced by some plant species is a natural source of biologically active compounds, and many of the hydrolytic enzymes are related to health benefits. Research on the characterization and industrial and pharmaceutical utility of latex has progressed in recent years. Latex proteins are associated with plants’ defense mechanisms, against attacks by fungi. In this respect, there are several biotechnological applications of antifungal proteins. Some findings reveal that antifungal proteins inhibit fungi by interrupting the synthesis of fungal cell walls or rupturing the membrane. Moreover, both phytopathogenic and clinical fungal strains are susceptible to latex proteins. The present review describes some important features of proteins isolated from plant latex which presented in vitro antifungal activities: protein classification, function, molecular weight, isoelectric point, as well as the fungal species that are inhibited by them. We also discuss their mechanisms of action.

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