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 (yo͝or′ĭ-dĭn′ē-əm) also u·re·di·um (yo͝o-rē′dē-əm)
n. pl. u·re·din·i·a (-dĭn′ē-ə) also u·re·di·a (-dē-ə)
A reddish pustulelike structure that is formed in the tissue of a plant infected by a rust fungus and produces urediniospores.

[New Latin ūrēdinium, from Latin ūrēdō, ūrēdin-, blight, from ūrere, to burn.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˌyʊər ɪˈdɪn i əm)

n., pl. -din•i•a (-ˈdɪn i ə)
the fruiting body of the rust fungi that bears urediospores.
[1905–10; < New Latin, = Latin ūrēdin-, s. of ūrēdō blight (see uredo)]
u`re•din′i•al, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
The scale for IT was 0= no symptom; 0;= produce dead spots or chlorosis reaction, does not produce uredinium; 1=Uredinium is very small, and few in number, often does not break down, have withered reaction around; 2=Uredinium were small to medium, and not broken, have withered and chlorosis reaction around; 3= Uredinium were medium size and Cultivars broken, and no dead reaction of surrounding tissue, but there is a slight chlorosis; 4=Uredinium were more and broken abundant, and no dead reaction of surrounding tissue, early chlorosis phenomenon is not obvious.Plants with IT of 0 to 2+ were considered resistant (R), and those with an IT of 3- to 4 were considered susceptible (S).
The incubation period was defined as the number of days from inoculation to rupture of the first uredinium [31], and it was 10 days in this study.
This apparent pleiotropic relationship is similar to the pleiotropic effect of Lr34 on the components of slow-rusting resistance, including a prolonged latent period, and reduced receptivity and uredinium size (Singh and Huerta-Espino, 2003).
Competitive effects are defined as the effect of a propagative unit (a urediniospore infecting a leaf, or a sporulating uredinium on a leaf) of one strain on the reproductive output (formation of uredinia from initial infections in the leaf, or production of urediniospores by uredinia on the leaf) of the other strain, relative to the effect of a unit of that other strain on its own reproductive output.
1: Cerotelium fici (A) Lucida drawings of urediniospores showing echinulate ornamentation (B) Uredinium showing urediniospores surrounded by several incurved paraphyses as seen by scanning electron microscope.