Glossary of Terms

A

Antheridium
 the male gametangium of Ascomycetes

Ascogonium
the female gametangium of Ascomycetes

Ascocarp
the fruiting body of Ascomycetes bearing or containing asci

Ascomycetes
a group of fungi producing their sexual spores, ascospores, within asci

Ascospore
a sexually  produced spore formed in an ascus

Ascus
a specialized sac-like cell where meiosis occurs and which encloses the ascospores

Asexual Reproduction
any type of reproduction not involving the union of gametes or mitosis

B

C

Cleistothecium
completely enclosed, nonostiolate ascocarp in which asci are distributed throughout the ascocarp

Chlorosis
yellowing of normally green plant tissue due to destruction of chlorophyll or inhibition or failure of chlorophyll formation

Conidiophore
a specialized hypha on which one or several conidia are produced

Conidium
(plural - Conidia ) an asexually produced fungus spore formed at the end of a conidiophore

D

Dichotomously Branched
branched in pairs which are approximately equal in size

Disease
any malfunctioning of host cells that results from continuous irritation by a pathogenic agent or environmental factor and leads to the development of symptoms

Disease Cycle
the chain of events involved in disease development including the life cycle of the pathogen and the effects of the disease on the
infected host

E

F

Fruiting Body
a complex fungal structure containing spores

Fungicide
a compound toxic to fungi

G

Gamete
a differentiated sex cell or a sex nucleus that fuses with another in sexual reproduction

Gametangium
a structure that contains gametes

Germ tube
the short hyphae that is formed by a spore as it begins to germinate

H

Haploid
containing a reduced (n) number of chromosomes

Haustorium
a specialized hyphal branch inside a living host cell that functions in nutrient absorption

Herbaceous Plant
a higher plant that does not develop woody tissues

Heterothallic Fungi
fungi producing compatible male and female gametes on physiologically distinct mycelia

Homothallic Fungus
fungus producing compatible male and female gametes on the same mycelium

Host
a plant that a parasitic organism invades and from which it obtains its nutrients

Host range
the various kinds of host plants that a particular parasite will invade

Hyaline
lacking color

Hypha
the slender, thread-like filament formed by a germinating spore, which will develop into a mycelium

Hypophyllous
on the lower surface of the leaf

I

Infection
the establishment of a parasite within a host plant

Infectious Disease
a disease that is caused by a pathogen, which can be spread from a diseased to a healthy plant

J

K

Karyogamy
the fusion of two nuclei

L

Leaf spot
a self limiting lesion on a leaf

Lesion
a localized area of discolored, diseased tissue

Life Cycle
the stage or successive stages in the growth and development of an organism that occur between the appearance and reappearance of the same stage of that organism

M

Meiosis
a pair of nuclear divisions in quick succession, one of which is reductional. As a result, four haploid nuclei are produced by this process

Mycelium
the mass of hyphae that comprises the thallus of most fungi

N

O

Odium
a thin walled free hyphal cell derived from fragmentation of a somatic hypha into component cells

Obligate Parasite
a parasite that, in nature, can grow and multiple only on or in living organisms

P

Q

R

S

Setose
surrounded or covered by bristles

Sexual
participating in or produced as a result of a union of nuclei in which meiosis takes place

Sign
the pathogen or its parts or products seen on a host plant

Spore
the reproductive unit of fungi consisting of one or more cells; it is analogous to the seed of green plants

Symptom
the external and internal reaction or alteration of a plant as a result of a disease

T

Teleomorph
the perfect stage of a fungi

Thallus
the vegetative body of a fungus

U

Uncinate
hooked, curled or coiled

V

W

X

Y

Z


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