black spot

/blak" spot"/ for 1; /blak" spot'/ for 2
1. Plant Pathol. a disease of plants, characterized by black spots on the fruit and foliage, twig lesions, defoliation, and rotting, caused by any of several fungi, as Diplocarpon rosae, or bacteria.
2. Brit.
a. a hazardous place in a road where accidents frequently occur.
b. a dangerous area or place.
Also, blackspot.
[1885-90]

* * *

also spelled  blackspot,  
 common disease of several plants that is caused by species of Pseudomonas bacteria or by many fungus species in the genera Asterina, Asterinella, Asteroma, Diplotheca, Glomerella, Gnomonia, Microthyriella, Placosphaeria, and Stigmea. Infections occur during damp periods and appear as round to irregular black leaf spots, sometimes on petioles, stems, and flower parts.

      Commonly, the term is used to mean black spot of roses (rose), a serious worldwide disease, except in arid regions, caused by the fungus Diplocarpon rosae. On rose plants, the spots are roundish and more than 1 cm (up to 0.5 inch) in diameter with fringed margins. Leaves on susceptible varieties turn yellow and drop early. Affected plants may defoliate twice in a season, are greatly weakened, produce fewer and inferior blooms, and are subject to canker diseases and winterkill. Large numbers of spores are formed in speck-size fruiting structures (acervuli) and disseminated by splashing rain, dew, overhead sprinkling, and gardeners working among wet plants. The spores germinate and penetrate rose tissue in 9 to 18 hours or longer; new leaf spots appear in 3 to 16 days and spores in 10 to 18 days. The cycle may be repeated throughout the growing season. Black spot may be controlled through adequate spraying or dusting.

* * *


Universalium. 2010.

Look at other dictionaries:

  • Black Spot — or black spot may refer to:* Black Spot, a plant disease caused by a fungus * The Black Spot, a literary device in Treasure Island, a novel by Robert Louis Stevenson * A black spot in highway traffic safety administration, is a section of roadway …   Wikipedia

  • black spot — black spots also blackspot 1) N COUNT If you describe a place, time, or part of a situation as a black spot, you mean that it is particularly bad or likely to cause problems. [BRIT] There are recognised black spots in marriages which can lead to… …   English dictionary

  • black spot — ► NOUN 1) Brit. a place marked by a particular problem or difficulty: an accident black spot. 2) a plant disease producing black blotches on the leaves …   English terms dictionary

  • black spot — black′ spot′ n. any of various diseases of plants characterized by the appearance of black spots on the fruit and foliage • Etymology: 1885–90 …   From formal English to slang

  • black spot — n a spotting of frozen meat caused by an imperfect fungus of the genus Cladosporium (C. herbarum) …   Medical dictionary

  • black spot — UK / US noun [countable] Word forms black spot : singular black spot plural black spots British 1) a) a place on a road where a lot of car accidents happen Gallows Corner is a notorious accident black spot. b) a place that has more problems than… …   English dictionary

  • black spot — akloji dėmė statusas T sritis fizika atitikmenys: angl. black spot; blind spot vok. blinder Fleck, m rus. слепое пятно, n pranc. tache aveugle, f …   Fizikos terminų žodynas

  • black spot — noun 1》 Brit. a place marked by a particular problem: an accident black spot. 2》 a fungal or bacterial disease of plants, producing black blotches on the leaves …   English new terms dictionary

  • black spot — noun Black spot is used after these nouns: ↑accident, ↑unemployment …   Collocations dictionary

  • black spot — /ˈblæk spɒt/ (say blak spot) noun any of various fungal infections causing black spots on plant foliage …   Australian English dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.