scholarly journals Histochemical observations on the sporogenous tissue and tapetum in the anther of Euphorbia.

CYTOLOGIA ◽  
1985 ◽  
Vol 50 (1) ◽  
pp. 39-48 ◽  
Author(s):  
C. K. Rudramuniyappa ◽  
B. G. Annigeri
Keyword(s):  
Sporogenous Tissue

In vitro studies on the induction of sporogenous tissue on leaves of cinnamon fern. I. Environmental factors

1972 ◽  
Vol 50 (12) ◽  
pp. 2673-2682 ◽  
Author(s):  
William H. Harvey ◽  
James D. Caponetti
Keyword(s):  
Environmental Factors ◽  
Light Intensity ◽  
Environmental Conditions ◽  
Light Exposure ◽  
Progressive Increase ◽  
Light Phase ◽  
Sporogenous Tissue ◽  
Light Darkness

Intact, set III, cinnamon fern cataphyll and frond primordia, which were shown to have no predisposition to fertility in situ, produced sporangia when excised and cultured under sterile conditions in Knudson's medium supplemented with various levels of sucrose and maintained on 11 different regimens of light, darkness, and temperature for 10 weeks. Increasing levels of sucrose resulted in increased fertility under all environmental conditions, but the highest percentage of fertility was obtained under conditions of continuous dark at 26 °C. As the length of the light phase of the photoperiods decreased, a progressive increase in induction of fertile leaves was observed, suggesting that periods of long light exposure are inhibitory to the initiation of sporangia. Conversely, as the light intensity was increased, an inhibition of sporophyll differentiation occurred. Sporangia excised from dark-induced sporophylls and cultured in the light produced viable spores which germinated yielding haploid gametophytes that ultimately produced sporophytes.

Seasonal temperature variations influence tapetum mitosis patterns associated with reproductive fitness

Genome ◽  
2014 ◽  
Vol 57 (9) ◽  
pp. 517-521 ◽  
Author(s):  
Umesh C. Lavania ◽  
Surochita Basu ◽  
Jyotsana Singh Kushwaha ◽  
Seshu Lavania
Keyword(s):  
Climate Change ◽  
Temperature Change ◽  
Reproductive Fitness ◽  
Seasonal Temperature ◽  
Seed Fertility ◽  
Mild Winter ◽  
Differential Behavior ◽  
Sporogenous Tissue ◽  
Differential Behaviour ◽  
Environmentally Sensitive

Environmental stress in plants impacts many biological processes, including male gametogenesis, and affects several cytological mechanisms that are strongly interrelated. To understand the likely impact of rising temperature on reproductive fitness in the climate change regime, a study of tapetal mitosis and its accompanying meiosis over seasons was made to elucidate the influence of temperature change on the cytological events occurring during microsporogenesis. For this we used two species of an environmentally sensitive plant system, i.e., genus Cymbopogon Sprengel (Poaceae), namely Cymbopogon nardus (L.) Rendle var. confertiflorus (Steud.) Bor (2n = 20) and Cymbopogon jwaruncusha (Jones) Schult. (2n = 20). Both species flower profusely during extreme summer (48 °C) and mild winter (15 °C) but support low and high seed fertility, respectively, in the two seasons. We have shown that tapetal mitotic patterns over seasons entail differential behavior for tapetal mitosis. During the process of tapetum development there are episodes of endomitosis that form either (i) an endopolyploid genomically imbalanced uninucleate and multinucleate tapetum, and (or) (ii) an acytokinetic multinucleate genomically balanced tapetum, with the progression of meiosis in the accompanying sporogenous tissue. The relative frequency of occurrence of the two types of tapetum mitosis patterns is significantly different in the two seasons, and it is found to be correlated with the temperature conditions. Whereas, the former (genomically imbalanced tapetum) are prevalent during the hot summer, the latter (genomically balanced tapetum) are frequent under optimal conditions. Such a differential behaviour in tapetal mitosis vis-à-vis temperature change is also correspondingly accompanied by substantial disturbances or regularity in meiotic anaphase disjunction. Both species show similar patterns. The study underpins that tapetal mitotic behaviour per se could be a reasonable indicator to elucidate the effect of climate change on reproductive fitness.

scholarly journals SlTDP1 Is Required To Specify Tapetum Identity And For The Regulation Of Redox Homeostasis In Tomato Anthers

2021 ◽  
Author(s):  
Blanca Salazar-Sarasua ◽  
María Jesús López-Martín ◽  
Edelín Roque ◽  
Rim Hamza ◽  
Luis Antonio Cañas ◽  
...  
Keyword(s):  
Early Stage ◽  
Redox Homeostasis ◽  
Loss Of Function ◽  
Ros Scavenging ◽  
Tomato Plants ◽  
Sporogenous Tissue ◽  
Ros Homeostasis ◽  
Ros Accumulation ◽  
Scavenging Enzymes ◽  
Mother Cells

ABSTRACTThe tapetum is a specialized layer of cells within the anther adjacent to the sporogenic tissue. During its short life, it provides nutrients, molecules and materials to the pollen mother cells and microsporocytes being essential during callose degradation and pollen wall formation. However, the acquisition of tapetal cell identity in tomato plants is a process still poorly understood. We report here the identification and characterization of SlTPD1 (Solanum lycopersicum TPD1), a gene specifically required for pollen development in tomato plants. Gene editing was used to generate loss-of-function Sltpd1 mutants that showed absence of tapetal tissue. In these plants, sporogenous cells developed but failed to complete meiosis resulting in complete male sterility. Transcriptomic analysis conducted in wild-type and mutant anthers at an early stage revealed the down regulation of a set of genes related to redox homeostasis. Indeed, Sltpd1 anthers showed a reduction of reactive oxygen species (ROS) accumulation at early stages and altered activity of ROS scavenging enzymes. The obtained results highlight the importance of ROS homeostasis in the interaction between the tapetum and the sporogenous tissue in tomato plants.One sentence summaryThe small protein SlTPD1 is required for tapetum formation in tomato, highlighting the role of this tissue in the regulation of redox homeostasis during male gametogenesis.

An acetolysis-resistant membrane investing tapetum and sporogenous tissue in the anthers of certain Compositae

1969 ◽  
Vol 47 (4) ◽  
pp. 541-542 ◽  
Author(s):  
J. Heslop-Harrison
Keyword(s):  
Pollen Grain ◽  
Sporogenous Tissue ◽  
Spore Mass ◽  
Parietal Tapetum

After the breakup of the meiotic tetrads, it is usual in the Compositae for the cells of the previously parietal tapetum to invade the anther loculus and form a Plasmodium ramifying between the young spores. In species of three tribes, Helenieae, Heliantheae, and Ambrosieae, an extratapetal membrane is formed at this time, which totally encloses the tapetum and the spore mass. The extratapetal membrane is resistant to acetolysis, and is considered to be chemically similar to the sporopollenin of the pollen grain exine.

scholarly journals Variations in Sulfhydryl Concentration During Microsporocyte Meiosis in the Anthers of Lilium and Trillium

1958 ◽  
Vol 4 (2) ◽  
pp. 157-161 ◽  
Author(s):  
Herbert Stern
Keyword(s):  
Sporogenous Tissue ◽  
Marked Drop

Anthers of lily and trillium were followed with respect to variations in protein and soluble sulfhydryls during meiosis and mitosis of the sporogenous tissue. In lily, the meiotic and mitotic cycles are each preceded by a rise in soluble —SH; in trillium there is only one rise which precedes meiosis. During division there is a marked drop in soluble —SH and a rise in soluble disulfides. Protein —SH remains approximately constant until diakinesis or metaphase when it falls briefly.

Aspects infrastructuraux des altérations des anthères de Silene dioica parasitées par Ustilago violacea

1980 ◽  
Vol 58 (4) ◽  
pp. 405-415 ◽  
Author(s):  
Jean-Claude Audran ◽  
Mekinto Batcho
Keyword(s):  
Early Stage ◽  
Structural Characteristics ◽  
Silene Dioica ◽  
Histological Changes ◽  
Ustilago Violacea ◽  
Dikaryotic Mycelium ◽  
Sporogenous Tissue ◽  
Superficial Tissues

The structural characteristics of the sporogenous and parietal tissues of healthy anthers of Silene dioica (L.) Clairv. (Caryophyllaceae) are described as well as those of anthers infected by Ustilago violacea (Pers.) Rouss. (Ustilaginales). In infected anthers, the invading dikaryotic mycelium grew intercellularly and very rarely penetrated the cells. The pathogen stopped stamen histogenesis at an early stage, causing necrosis specifically of the sporogenous tissue either directly or following hypertrophy. Five stages were distinguished during the histological modifications leading to anther destruction. (1) First, the mycelium developed in the anther filament and spread throughout the superficial tissues of the anther without causing histological changes in the anther. (2) Then, some sporogenous cells began to show necrosis and formed compact masses. (3) An increasing number of sporogenous cells became necrotic following strong vacuolisation and hypertrophy. (4) Hyphae grew profusely in the necrotic mass of sporogenic cells. (5) Finally, the fungus produced teliospores which filled the sporangial cavity.

Studies of Cintractia axicola. I. Development of the sorus

1969 ◽  
Vol 17 (1) ◽  
pp. 25 ◽  
Author(s):  
IC Tommerup ◽  
RFN Langdon
Keyword(s):  
Nuclear Fusion ◽  
Cyperus Rotundus ◽  
Sporogenous Tissue

Penetration of the host and development of the sorus of the smut Cintractia axicola on plants of Fimbristylis dichotoma and Cyperus rotundus was studied. Following germination of the teleutospores dikaryotic hyphae of promycelial origin penetrate the epidermis of the peduncle directly. From the point of penetration mycelium spreads mostly intracellularly through the tissues of the host. The cells of the epidermis become filled with monokaryotic mycelium which constitutes the fungal sheath. Internal to the epidermis, mycelium which is dikaryotic accumulates first in the subepidermal cells and then progressively occupies tissues of the peduncle. A stroma, pockets of sporogenous tissue, and a columella form. Nuclear fusion occurs in developing spores at the time they are differentiated from the parent hyphae. Sori may form in florets, groups of florets, or whole spikelets. The mode of differentiation of hyphae giving rise to sheath, stroma, spores, and columella is the same as described for sori which form at the bases of peduncles.

scholarly journals Microsporogenesis and pollen grains in Silene dioica (L.) Cl. and alterations in its anthers parasited by Ustilago violacea (Pers.) Rouss. (Ustilaginales)

2014 ◽  
Vol 50 (1-2) ◽  
pp. 29-32 ◽  
Author(s):  
Jean-Claude Audran ◽  
Mekinto Batcho
Keyword(s):  
Early Stage ◽  
Pollen Grains ◽  
Silene Dioica ◽  
Electron Microscopic ◽  
Ustilago Violacea ◽  
Sporogenous Tissue ◽  
Microscopic Techniques

Healthy and infected anthers are comparatively studied with optical and electron microscopic techniques. The fungus stops the stamen histogenesis at an early stage and destroys specifically the sporogenous tissue.

scholarly journals Ultrastructural studies on the sporogenous tissue and anther wall of Leucojum aestivum (amaryllidaceae) in different developmental stages

2012 ◽  
Vol 84 (4) ◽  
pp. 951-960 ◽  
Author(s):  
Nuran Ekici ◽  
Feruzan Dane
Keyword(s):  
Developmental Stages ◽  
Male Gametophyte ◽  
Anther Wall ◽  
Pollen Mother Cells ◽  
Ultrastructural Studies ◽  
Leucojum Aestivum ◽  
Sporogenous Tissue ◽  
Mother Cells ◽  
Polar Distribution ◽  
Early Phases

In this study, ultrastructures of anther wall and sporogenous tissue of Leucojum aestivum were investigated during different developmental stages. Cytomictic channels were seen between pollen mother cells during prophase I. Polar distribution was described in the organelle content of pollen mother cells and microspores in early phases of microsporogenesis and also in pollen mitosis. Active secretion was observed in tapetal cells. Previous reports about developmental stages of male gametophyte were compared with the results of this study.

Sign in / Sign up

Export Citation Format

Share Document