spot

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spot,

fish: see croakercroaker,
member of the abundant and varied family Sciaenidae, carnivorous, spiny-finned fishes including the weakfishes, the drums, and the kingcroakers (or kingfish). The croaker has a compressed, elongated body similar to that of the bass.
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The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Spot

 

any one of several diseases of agricultural plants characterized by formation of blotches of dead cells on leaves, stems, fruits, and other plant parts; a specific type of necrosis. Spots are caused by inadequate soil nutrition; air pollution; burns; and pathogenic fungi (most often, imperfect hyphomycetic fungi of the genera Ramularia, Cercospora, and Macrosporium and pycnidial fungi of the genera Septoria, Ascochyta, and Phoma; less commonly such perfect fungi as ascomycetes of the genus Pseudopeziza), bacteria (genera Pseudomonas and X anthomonas), and viruses.

The outward appearance of the spots is determined by the relationship between and the specific features of the parasite and the plant host. The causative agents, which usually spread throughout the tissues, encounter opposition from the plant host in the form of mechanical and chemical barriers. A mechanical barrier is caused by the formation of a cork layer on the boundary between healthy and diseased tissue; the cork localizes the focus of infection. For example, in drupaceous crops infected with the fungus Clasterosporium carpophilum or the bacterium Xanthomonas pruni, the affected tissue, after the formation of the cork layer, falls out together with the pathogen. Chemical barriers form owing to the accumulation in the affected cells and the cells adjacent to them of phenolic substances that are toxic to the parasite (specifically anthocyanins and products of their oxidation). If intrusion of the parasite is accompanied by a severe protective reaction of the plant, a small necrotic spot is formed and development of the causative agent is curtailed. When, however, the protective action is insufficient to localize the infection, the spots slowly enlarge (for example, macrosporiosis of potatoes, tomatoes, cotton; phomosis of sugar beet). Sometimes check zones in the form of concentric rings are readily observable on the spots.

When the causative agents are pathogenic fungi, there arise variously shaped and colored dry spots, upon whose surface one may observe the spore carriers of the fungus. Bacterial spots are characterized by the formation of tiny blotches surrounded by chlorotic aureoles; sometimes droplets of resin emerge on the spots (for example, gummosis of cotton). Spots produced by viruses are localized along the veins or form characteristic rings and designs. Their coloration may be red (with accumulation of anthocyanins), dark brown, gray, black (with accumulation of melanins), or white (with decolorization of pigments).

The resulting atrophy of parts of leaves, fruits, and stems decreases the photosynthetic surface of the plant and the plant’s productivity. With widespread infection, the spots merge. This may result in the mass falling of leaves and fruits and the drying of stems, significantly decreasing the yield of agricultural crops. In some cases, even a minor infection may bring great harm. For example, a single infection of an alfalfa petiole with the pathogenic ascomycete Pseudopeziza medicaginis close to the place where the leaf blade is attached leads to leaf fall. For a discussion of control measures against spots of agricultural plants seeBACTERIAL DISEASES OF PLANTS, VIRAL PLANT DISEASES, and FUNGAL DISEASES OF PLANTS.

REFERENCE

Gorlenko, M. V. Sel’skokhoziaistvennaia fitopatologiia. Moscow, 1968.

IU. T. D’IAKOV

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

spot

[spät]
(electronics)
In a cathode-ray tube, the area instantaneously affected by the impact of an electron beam.
(ordnance)
To determine, by observation, deviations of ordnance from the target for the purpose of supplying necessary information for adjustment of fire.
To place ordnance in a proper location.
To locate or espy something, as an aircraft or troop concentration.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

spotting

A paint-film defect characterized by small circular or irregular areas having color or gloss different from that of the surrounding background.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.

Spot

dog accompanying Sally, Dick, and Jane in primers. [Am. Cult.: Misc.]
See: Dogs
Allusions—Cultural, Literary, Biblical, and Historical: A Thematic Dictionary. Copyright 2008 The Gale Group, Inc. All rights reserved.

spot

1. a geographical area that is restricted in extent
2. a blemish of the skin, esp a pimple or one occurring through some disease
3. a position or length of time in a show assigned to a specific performer
4. short for spotlight
5. in billiards
a. the white ball that is distinguished from the plain by a mark or spot
b. the player using this ball
6. Billiards snooker one of several small black dots on a table that mark where a ball is to be placed
7. Commerce
a. denoting or relating to goods, currencies, or securities available for immediate delivery and payment
b. involving immediate cash payment
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

SPOT

(Smart Personal Objects Technology) See Microsoft Smart Watch.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.
References in periodicals archive ?
Here are a few of her famous observations: Old age is when the liver spots show through your gloves; My photographs don't do me justice - they just look like me; I have a tremendous sex drive, my boyfriend lives 40 miles away; Whatever you may look like, marry a man your own age - as your beauty fades, so will his eyesight; Housework can't kill you but why take a chance?; The best way to get rid of kitchen odours is to eat out; I want my children to have all the things I couldn't afford.
Apart from that people with more number of sunburns, sun damaged skin like liver spots, actinic keratosis and solar elastosis, are at a greater risk of developing skin cancer.
Older individuals throughout the world suffering from liver spots or age spots, and other age-related skin darkening conditions, are increasingly turning to skin lightening formulations in an effort to maintain what is perceived to be clearer and more youthful looking skin.
While Scarguard shrinks the size of a scar, Scarlight MD lightens the scar's appearance and can also be used to lighten under-eye circles, age spots, liver spots and freckles.
Still no word from ITV as to why they based a prime time series around a rude OAP with liver spots. I demand an explanation.
8:43 a.m.: Lucas Road, runaway dog, white English pointer with liver spots, name is Secret.
Age spots (also called "liver spots," although they have no connection with the liver) are caused by the sun.
Q MY mother is terribly concerned about liver spots she has on her hands.
." I mumble, minutely examining the liver spots I've noticed appearing on the backs of my hands recently.
The gel formula is also effective on other hyperpigmented skin, the company says, and can be used to lighten such skin discolorations as age spots, liver spots, freckles and even dark circles under the eyes.
According to the BusinessWeek article, while the baby boomer generation is comfortable with the aging process, they still want to look and be healthy--they want to age "successfully." "Many consumers experiencing their first liver spots and crows feet are actually comfortable in their skin," the article said.