THE EFFECT OF EXTREME SHADE UPON LEAF FORM AND STRUCTURE IN VICIA AMERICANA

1955 ◽  
Vol 33 (4) ◽  
pp. 293-297 ◽  
Author(s):  
R. G. H. Cormack
Keyword(s):  
Comparative Study ◽  
Internal Structure ◽  
Flowering Plant ◽  
Mesophyll Cells ◽  
Leaf Form

A comparative study of light and shade leaflets of a common flowering plant (Vicia americana) reveals striking differences in leaflet form, size, thickness, and internal structure. The marked thinness of shade leaflets is due to the failure of the mesophyll cells to enlarge, and their peculiar folded form is attributed to the same cause.

ALTERATION OF LEAF SIZE AND STRUCTURE IN CONVALLARIA MAJALIS CAUSED BY EXTREME SHADE

1962 ◽  
Vol 40 (3) ◽  
pp. 383-387
Author(s):  
R. G. H. Cormack
Keyword(s):  
Internal Structure ◽  
Anatomical Study ◽  
Leaf Size ◽  
Common Garden ◽  
Mesophyll Cells ◽  
Leaf Form ◽  
Convallaria Majalis ◽  
Garden Plant ◽  
Shade Leaves ◽  
Size And Structure

This paper presents a comparative anatomical study of normal shade and extreme shade leaves of a common garden plant (Convallaria majalis L.). Striking differences in leaf form, shape, size, thickness, and internal structure were observed. The failure of the mesophyll cells to enlarge is thought to account for the marked thinness and peculiarly folded condition of extreme shade leaves.

scholarly journals Populistic Rhetoric: Structures Over Senses

2021 ◽  
Vol 42 (4) ◽  
pp. 65-92
Author(s):  
Patrycja Pichnicka-Trivedi
Keyword(s):  
Structural Analysis ◽  
Comparative Study ◽  
Internal Structure ◽  
Main Tool ◽  
Social Conditions ◽  
Global World

This article makes a comparative study of American and Polish rightist populisms and their ways of operating using structural analysis of their discourses as a main tool of examination. It aims to prove that those are indeed structural similarities that are responsible for the success of populisms in diverse environments. While examining examples of populist rhetorics and noticing the surprising efficacy of similar discourse in different political and social conditions, I expose internal structure of populism(s). I state that populism(s) is constructed mostly by and on empty signifiers. Those signifiers can then be matched in broader structures, of which the most fundamental one is the opposition: “We”—“Them”. Such mythological structures are flexible enough so that any subject or object can be inscribed into them. They are also flexible enough to transgress the borders of one domain and to transgress state borders: to “wander” around the global world.

Anchorage behavior of grouting sleeves under uniaxial and cyclic loading-A comparative study of the internal structure of sleeves

2022 ◽  
pp. 104057
Author(s):  
Yubo Li ◽  
Luchuan Zhang ◽  
Quangang Zhang ◽  
Xingyang He ◽  
Jingdong Wang ◽  
...  
Keyword(s):  
Cyclic Loading ◽  
Comparative Study ◽  
Internal Structure

Étude ultrastructurale des modifications induites par Exserohilum turcicum chez le limbe de Zea mays – Effet du gène de résistance Ht-1

1987 ◽  
Vol 65 (10) ◽  
pp. 2061-2066
Author(s):  
B. Gélie ◽  
M. Petitprez ◽  
A. Souvre ◽  
L. Albertini
Keyword(s):  
Zea Mays ◽  
Comparative Study ◽  
Inbred Lines ◽  
Bundle Sheath ◽  
Ultrastructural Changes ◽  
Exserohilum Turcicum ◽  
Mesophyll Cells ◽  
Isogenic Lines ◽  
Bundle Sheath Cells ◽  
Cellular Components

Ultrastructural changes induced by Exserohilum turcicum (Pass.) Leonard et Suggs in maize leaf cells are observed 24 to 72 h after inoculation, in a comparative study between two isogenic lines with or without the Ht-1 gene. In the susceptible plants (without Ht-1), the plasmalemma and the tonoplast of the mesophyll cells are the first cellular components altered, followed by disorganisation and alteration of organelles, which become scattered throughout the cell. Chloroplasts in particular seem to be very sensitive to the toxic action of the pathogen, which causes disruption of their envelope and grana. Bundle sheath cells are altered later and to a lesser extent than the mesophyll cells. In Ht-1 monogenic resistant inbred lines, cytoplasmic residues of prematurely dead cells surround healthy mesophyll cells protecting them and stimulating their activity and resulting in stabilization of the pathotoxic process 36 to 48 h after inoculation.

scholarly journals A COMPARATIVE STUDY OF PERMEABILITY IN PLANTS

1919 ◽  
Vol 1 (3) ◽  
pp. 299-304 ◽  
Author(s):  
W. J. V. Osterhout
Keyword(s):  
Comparative Study ◽  
Green Alga ◽  
Brown Alga ◽  
Red Alga ◽  
Flowering Plant ◽  
Quantitative Studies

Quantitative studies on Laminaria (a brown alga), Ulva (a green alga), Rhodymenia (a red alga), and Zostera (a flowering plant) show that the behavior of these plants, in respect to changes in permeability, is essentially alike in all cases.

scholarly journals A Comparative study of Andra bhasha bhushanam and Tolkappiyam

2021 ◽  
pp. 76-92
Author(s):  
Savithri Ch
Keyword(s):  
Comparative Study ◽  
Internal Structure ◽  
Structure Type ◽  
Word Usage ◽  
Under Five ◽  
Construction Methods ◽  
Alternative Formula ◽  
Structure Relation ◽  
The Subject ◽  
Future Reference

This review examines the subject under five sub-headings: writing intent, writing structure, Type of techniques, vocabulary, and spelling observation. Of these, the structure of the text is examined under two sub-headings, external structure and internal structure. Among the 32 writing techniques mentioned by Tolkappiyar, 1. Writing purpose, 2. Section order, 3. Codification expression, 4. Section expression, 5. Semantic coordination, 6. Fictional gestures, 7. Meaningful reference, 8. Alternative formula entry, 9. Future reference, 10. Sutra and examples are examined in bilingual grammars. In formulaic construction methods such as sutrartham, sutra structure, relation between sutras, gana, nipatam are taken into consideration. In the alphabet section, topics such as distribution of letters, creation of letters, conjugation, and word usage are examined. Finally, at the end of the character the 10 things identified in the bilingual grammars examined comparatively are revealed and the table of reference is compiled.

Electron Microscopic Evidence for Membrane Bound Structures in Plant Vacuoles

1967 ◽  
Vol 25 ◽  
pp. 76-77 ◽  
Author(s):  
W. W. Thomson
Keyword(s):  
Electron Microscope ◽  
Granular Material ◽  
Internal Structure ◽  
Plant Tissue ◽  
Mature Plant ◽  
Electron Microscopic ◽  
Mesophyll Cells ◽  
Microscopic Evidence ◽  
Plant Vacuoles ◽  
Membrane Bound

To date, most electron microscope studies of mature plant tissue have shown the vacuole to be generally devoid of internal structure except for irregular aggregates of electron dense granular material. However, after gluturaldehyde-osmium fixation, membrane bound structures are frequently observed in the vacuoles of the mesophyll cells of the xerophytic plant, Tamarix (Fig. 1). These structures are generally ovoid in shape and range in length from .5 to 1.6 μ.Some of the membrane bound, vacuolar inclusions are bounded by two membranes which are often tightly opposed (Fig. 2, arrow). Other inclusions are bounded by a single tripartate membrane (Fig. 3). The internal organization of the inclusions consists of tubules surrounded by an electron-translucent matrix (Fig. 2 & 3). The tubules measure about 350 A in diameter and frequently extend in arrays parallel to the bounding membrane. Occasionally vesicles about 1000 A in diameter are also observed in the inclusions (Fig. 1).

scholarly journals First Report of Powdery Mildew Caused by Leveillula clavata on Poinsettia (Euphorbia pulcherrima) in Italy

Plant Disease ◽  
2006 ◽  
Vol 90 (6) ◽  
pp. 827-827 ◽  
Author(s):  
A. Garibaldi ◽  
A. Minuto ◽  
M. L. Gullino
Keyword(s):  
Powdery Mildew ◽  
Morphological Characteristics ◽  
Plant Diseases ◽  
Flowering Plant ◽  
Pathogenicity Test ◽  
Euphorbia Pulcherrima ◽  
Conidial Suspension ◽  
Mesophyll Cells ◽  
First Report ◽  
Young Leaves

Euphorbia pulcherrima (poinsettia) is a winter-flowering plant grown primarily for Christmas sales. During the fall of 2005, severe outbreaks of a previously unknown powdery mildew were observed on cv. Gala in a commercial greenhouse located in Albenga (northern Italy). The abaxial surfaces of green leaves were irregularly covered with white mycelia and conidia, while the adaxial surfaces only showed slight chlorotic round lesions. As the disease progressed, mycelium turned from rose to reddish. Symptoms and signs were never observed on red bracts. Conidia were clavate (55 to 95 × 20 to 40 μm, average 70 × 23 μm) and borne singly on conidiophores that emerged through stomata. On the basis of host, morphological characteristics, and microscopic observations of the intercellular colonization of mesophyll cells, the pathogen was identified as a species of Oidiopsis. Although chasmothecia were not observed, the causal agent based on the literature is believed to be Leveillula clavata Nour (2). Pathogenicity was confirmed by inoculating young leaves of three 4-month-old E. pulcherrima plants, cv. Gala, with a conidial suspension (3 × 105 conidia/ml). Three noninoculated plants sprayed with deionized water served as control. After inoculation, plants were maintained in a growth chamber at 18°C with relative humidity ranging from 56 to 100%. After 20 days, powdery mildew symptoms were observed on leaves of inoculated plants. Noninoculated plants remained healthy. The pathogenicity test was carried out twice. To our knowledge, this is the first report of L. clavata on poinsettia in Italy and probably in Europe. It presently is restricted to a few commercial farms. L. clavata previously has been observed on poinsettia in Kenya (1,2). Voucher specimens are available at the AGROINNOVA Collection, University of Torino. References: (1) M. L. Daughtrey et al. Powdery Mildew Diseases. Pages 39–42 in: Compendium of Flowering Potted Plant Diseases. The American Phytopathological Society, St. Paul, MN, 1995. (2) M. A. Nour. Trans. Brit. Mycol. Soc. 40:477, 1957.

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